A careful couple of minutes of filing made sure it ran freely. On the outrun to the back of the engine of the cable I mounted two rubber P-clips to guide the cable across.

I think I’ll put some shields on top of the valve covers later on, which can then neatly hide the cable from sight.

As said earlier, I would rather have the electronic throttle valve, but for safety reasons that’s not allowed.

In the batch of parts I collected last week, I got the correct length drive-belt. Installing this is also a job of two seconds. The coverage on the pulley isn’t that big, but the belt only has to drive the  alternator, so it should be ok.

Startmotor can be bolted on now I have the correct length of the bolts. It’s pretty close to the exhaust, I could not even get it assembled without removing the header, so the starter will probably need some heat shielding. 

On to the front, there are six bolts on the suspension which need their head drilled for the lock-wire. Mostly a patience job, making sure the bit gets cooled properly and preventing to much pressure on it. 5 bolts went fine, during the sixth the drill-bit broke. As such that isn’t a disaster, you count on the smaller bits to break soon, but the bit got stuck in the bolt! The bolts are jaguar specific and as such a rip-off (around the € 10,- mark I believe). Having no choice, I ordered a new one.

Having the bench drill now is essential, a hole like below just would not be possible by hand. (1.5mm hole, 2.5mm finish)

Back to the back again. The handbrake mechanism comes with two extra helper springs which somehow need to be attached to the chassis. There are two or three locations which would be suitable, but only one of them was reachable with the rivet tool I have. It remains scary to drill holes in the chassis.

At the right bottom you can see the black dot of a more preferable location (it pulls on the spring straight instead of in a slight angle), but unreachable for my tool.

Starting at the headers, which are quite nicely made, I noticed that on the right side the frontmost sparkplug lead and the second frontmost on the left, are a bit to close to the header for my taste. It’s nearly touching the header on the left side and completely touching it on the right side.

The other three are positioned much better in between the headers. Perhaps the alu heat shields can be made a bit shorter?

At the back of the chassis the exhaust is fitted with what looks like a piece of old tire. I drilled three holes in the rubber, bolted it onto the bracket and cut a bit of the rubber to make it look neater.

The U-brackets go through and together they hold the middle piece of the exhaust pipes.

Here’s an overview picture of the complete underslung exhaust line. It’s quite different from the more traditional (in GD terms) exhaust where the pipes are together in the center.

I had hoped the ends were a bit closer together, but there’s not much more room to bring them closer, given the current size dampers.

The gearbox was the bottleneck for delivery, (Tremec == GM so that may have something to do with it). It is here now but still without a flywheel and clutch assembly, so the only thing I can can do with it is temporarily mount it on the adapterplate and bell-housing and put it away for a while until the other bits arrive.

And finally, the modified thermostat outlet. I’m going to polish that a bit later on to smooth out the welds a bit. Also, there are basically 2 ways to mount the outlet. Shown here is the one where the outlet is most ‘outwards’. If the outlet is turned 180 degrees it moves a bit inwards. When the engine goes in the chassis I’ll have to revisit this too, judging what’s best at that time.

In one of the drawers at speedon Mischa found something that could fit, and with a bit of effort, it indeed did.

(apologies for the blurry picture) With a bit of sanding on both parts, i.e. the cable and and the bracket, made it fit.

The ECU has arrived too with a nice semi-assembled harness. Now I need a handful of connectors and I should then be able to construct a complete harnes and finish that part.

Let’s hope this time the cracks will not appear. Having to clear out the garage, store everything somewhere and put everything back is definitely not my idea of a good time.

On the cobra-building front it’s a bit quiet due to lack of parts, though I could do a few jobs on the chassis and suspension I guess, but for many of them I want to be able to take measurements of the engine, gearbox and other stuff before I do them.

I have been assured that the parts will be available for collection next week, so it should not be that long before I can get cracking at a slightly higher pace.

Again, I have to applaud Gardner Douglas for their ‘fit’. The differential and the chassis get together by 8 bolts, 6 of which drop in pretty easily and the rear two need a little flexing of the diff cage; exactly as outlined in the build video.

Today I rolled the chassis to the garage of a nearby friend. It will stay there for the next week while work is being done in the garage. My girlfriend did take some pictures of the cobra’s maiden voyage. Alas, there was no card in the camera, so no pictures of that. (Not that it was that spectacular anyways.)

The trip, however small, was useful though. You get all sorts of information you do not get by keeping the chassis static. Here’s what I learned in 300 meters rolling the car from one garage to the next:

• the routing of the brakeline needs rethinking, on full steer it touches the tires; (I imagine it will be even worse with the wider wheels which will be fitted)
• there was a slight ‘tick’ at the rear left (hand-)brake caliper, could be the brake-pad;
• old tires, all different and a suspension not setup make for a crappy ride;
• it is very easy to lose nuts and bolts if they are not tightened;
• inertia of moving mass is easily underestimated;

So, not much to do for the next week but nag with my suppliers for delivery of the gearbox, which seems to be the bottleneck in the delivery. The gearbox fit also determines the precise length of the propshaft (so I’ve been told), so partial delivery also doesn’t make sense either. Patience…

So, that means we’ll need to clear out the whole garage, again, and having some wheels on the chassis makes that a whole lot easier. Ideally I want to have the suspension set-up completely by that date, but we’ll see.

One thing I noticed at the front was that the damper bracket opening was a bit smaller than the one on the left. This is probably caused by the welding process which puts strain on the metal and causes it to bend. We’re talking 2 milimeters I think. With a piece of thread and two M12 nuts I carefully widened the bracket a bit, just enough to get proper clearance on the damper.

Apart from one bolt I’m missing for the front (the one I had got damaged somehow) I’m also going to need two pieces of brake pipe for connecting the flexible hose to the front calipers. Looking at most other GD builds and the pictures I have from GD, the routing often does not make sense to me, so I’ve experimented with some different configurations. Basically, there are 2 things to vary:

1. the positioning of the donor bracket (upside down / normal);
2. routing of the flexible brake hose, what I’ve called ‘north’ and ’south’.

Positioning the bracket seemed to quickly lead to the ‘upside down’ solution for me (see also Simon’s post, although he reaches the opposite conclusion)

Next, the routing of the flexible brake hose. The ‘northbound’ routing seemed to work best for me. It does not come anywhere near any suspension part, neither in full bump, full droop and at both extremes of the steering.

I find that another advantage of the northbound route is that the routing of the fixed piping is greatly simplified, just needing a short piece with two bends, instead of routing it through the caliper openings.

It may of course be the case I’m missing something completely, as the setup with the upside down bracket and the northbound routing of the hose is basically different than everyone elses setup?

I double checked the torque on the drive shaft nu and got a helpful email from Terry about it too. Torqued it to 136Nm and put in the cotter pin.

The overview Terry sent me had torque numbers for the diff cover nuts as well, so out came the nord-lock washers again and the torque wrench. Probably not that important, but alas, looks nice at least.

Last job was deciding wether to fit the flimsy covers for the drive shafts. General consensus on the fora was a big no-no, so that made the decision a bit easier.

So, rear end done! All that’s left now is to fit it to the chassis. (Likely I’ll come up with new jobs for it soon, but my list is empty for now)

Starting with the original 5 shims (although I think the original shims were of different thickness) turned out to be ok. I also started with the original setup of 3 shims to the front and 2 shims at the back. This gave me a 4.4° on the left side and 5.0° on the right side of the car.

Leaving the left side of the car alone, I moved all 3 shims to the back and that gave me 4.5° on the right side.

Should be close enough for now. The measurement is sort of ‘an estimate of what it should be’ at the moment. It does not really matter what the castor is (within reason obviously) as long as both sides are equal, we should be good to go. (Not that I have hands-on experience with this, it’s all theory for me still)

I’ve got a bit of a routine by now for the final assembly of a part of the car. Roughly it goes like:

1. clean all the parts;
2. put on the appropriate (nord-lock) washer;
3. put some copper grease on the threads;
4. hand-tighten the nuts;
5. get out the torque-wrench;
6. get back into the office to look up the torque requirements (optional step in theory, I always forget what the torque was);
7. torque em-up;
8. mark with nail-polish that it’s done.

(and take some pictures in between all that)

So, what’s left for the rear end?

• I want to replace the straight grease nipples on the Upper Joints with bended ones, as the straight ones seem unreachable, at least with my grease gun;
• need to double check the torque on the big castellated nuts at the end of the drive-shafts keeping the hub in place, 75 Nm seems a bit low;
• the original jag had some protective covers for the drive shafts, should I fit these? They seem a bit flimsy to me;
• mount the whole thing to the chassis obviously.

I think that is about it.

Having both the hubs completed, I wanted to do a quick measurement of rear toe-in (or, let’s hope not, toe-out). So, clamped the laser to both hubs and marked the two projections on the garage-door.

Result: a bit more than 5mm overall toe-in over 4 meters. It’s on the good side of the scale at least! (If it had not been I would not have known how to correct it BTW). The value seems a bit on the low end of the acceptable range, but once the rear-end is in the chassis, I’ll do some more detailed measurements.

Rest of the day was filled with entertaining some friends coming over and a couple of minor jobs, one of which was to paint the upper ball joints as they started to show some rust. We can’t have that, obviously!

Here’s a rundown of the list of stuff I’m waiting for:

• engine mounts
• Tremex TKO 600 gearbox
• propshaft
• complete ss exhaust + headers

The position of the exhaust will be a bit different at the back. Instead of the two exhaust pipes in the centre as is common for GD type cobra’s,

or an option seen lately, at the outside:

Mine will be somewhere in between those two types. I like the wider looks of the exhausts, but not too wide as in the picture above, so mine will be situated between the lights and the vertical chrome thingies.

• omex 710 ECU + wiring

The omex needs a little adjusting (amplification I think it is called) to be able to drive the injectors of the LS2 directly.

• alternator + bracket
• starter motor
• air intake box + filter
• radiator + fan kit
• straight thermostat outlet

The thermostat on the LS2 is normally at an angle, which does not fit in the GD chassis, so a straight version needs to be mounted. (if you look at this picture at flickr you’ll see the notes about the thermostat etc. I’m hoping to get those notes working on this blog directly someday.)

• SS header tank
• several hoses and wiring

Hoses in black, wiring semi-assembled, courtesy of the omex guys.

• fuel pump and filter

I would like to assemble the fuel pump like so:

The above is a euro chassis, not the jag based one I have, so we’ll have to see if there is enough room (esp. with the brake discs inboard).

• mechanical throttle

Apparently the electronic throttle is not allowed, so it needs to be replaced by a mechanical one. Not sure what the precise reason for this is. but my guess would be that it has something to do with paranoia about (aftermarket) ECU’s going berzerk and giving an uncontrollable full open throttle signal, with the imaginable consequences of that (esp. when an automatic gearbox is fitted).

So, lots to do when the stuff gets here.

I should have photographed a measuring tape next to the marks, but it’s way less than an inch, so I guess I’m in the clear.

Apparently my measurements weren’t that bad and I got a bit lucky. Measured endfloat now was 0.055 mm which corresponds to just a bit more than 0.002″. This is just above the minimum. Phew!

So, the all trial assembly to the complete rear end is now complete. What is left is the right-side camber shims (waiting for delivery) and measuring toe-in.

One thing I noticed was that there is some play on the left side of the output-shaft of the diff. That is, i can turn the brake-disc a bit without a corresponding movement of the input shaft. The right side has this as well, but much less. I’ll have to consult a jag expert to assess the limits on this. Mr. Haynes does only talk of excessive crownwheel to pinion backlash as the cause of a problem, but not how much of this backlash is allowed (maximally).

Next, I created a dummy shaft for the outer fulcrum, having a slightly smaller width as the hub. This simplifies assembling the hub to the wishbone considerably and makes sure the shims which are inside the fulcrum stay properly positioned.

The “hub—wishbone fit” was pretty much dead on. There are shims to make sure the hub is centred and to prevent bending the ends of the wishbone. I had bought a set of 8 or so but I could only fit (with considerable effort) one shim of 3 or 8 thou (cant remember). Not sure how critical this is.

Next up was setting up the lower wishbone having a 2″ downward slope over its length; presumably emulating the normal ride-height like that. Fitting shims between the drive-shaft and the brake-disc makes it easy to adjust the camber. The one-tenth of a degree negative camber should do just fine for now. I bet I need to revisit this once the car is completed and the proper ride-height is determined.

The big nut on the drive shaft needs to be torqued up (only to 75Nm apparently, which seems small for such a big boy). Doing that is somewhat awkward on just the hub, on the complete assembly however it is basically just a matter of ‘putting the thing on the handbrake’ and torque up the nut. Also the previously determined endfloat can be checked again now, which I will do tomorrow.

For the 4 inner lock nuts I’ve have fitted some temporary nuts for now; to be replaced with the metal-lock nuts once the whole assembly is attached to the chassis.

So, for the other side, I still need the inner oil seal and a set of shims to be able to complete it. They should arrive this week.

This completes one rear hub. To complete the other one I’m waiting on the (extra thick) spacer and another inner oil seal.

So, out it came again and I’ll have to order a new one. No progress made today

…and greasing up the bearing.

After placing the housing on top of the bearing and filling the cavity with lots of grease, the inner bearing can be driven in, but not completely. Formally, a jaguar specific tool (J15 or something like that) should be used to put pressure on the bearing. This tools contains a machined edge with a specific height (0.152″ I think) which makes sure the bearing is not driven in completely. By leaving a little bit of room a (large) endfloat can be measured and from there the necessary spacer thickness can be calculated. Not having this tool I ordered the thickest spacer (0.148″) for an alternative procedure.

With this spacer on top of the inner bearing the whole hub was put under the press to drive in the bearing. When the spacer is flat with the bearing the endfloat can be measured.

In my case the endfloat was 0.016″ The target endfloat is between 0.002″ and 0.006″, aiming at the average 0.004″. So, instead of the 0.148″ spacer I would need a 0.148″ – 0.012″ = 0.136″ which is exactly the size I took out of the donor part, so I can reuse that one.

This result was expected for one hub only though. One of the hubs had to be replaced because of a crack. It is likely that this hub has different dimensions and another size spacer will be needed. Doing the same procedure for the other hub revealed that the 0.148″ spacer would lead to an endfloat of near zero ?!?

Hmm…

So, I would need a spacer with a minimum thickness of 0.150″ (leading to the minimal endfloat of 0.002″) This spacer used to exist, but apparently not anymore. Need to sleep on this one what to do here.

There are a couple of hurdles to overcome. First, when the thing gets hot gloves are mandatory which makes handling the piece more cumbersome and handling the thrower quickly but steadily over the hub proved to be quite a dexterity challenge.

Next, to much heat will ruin the passivation layer on the zinc, so I do not want to heat them up to the point where that happens.

And third, the heating will expand the part, but we’re talking parts of millimetres here; I figured about .5 mm difference between the cold and heated part. This means we’ll have to make sure the cold part is brought within that range. There’s also not much room for error.

So, first thing was to do a trial run to get some feel for the procedure and the measurements. The cold part inner diameter was about .8mm smaller than the diameter of the edge. Heating did not make it possible to fit the part but clearly showed a difference in size. I had the hub in the freezer overnight which may have helped a bit too, size-wise.

So, the only thing I could think of was putting the ring in a reference position (cold) and marking how far the circumference would go over the edge by pushing sort of in the same manner I would be able to do while handling the hot part. Marking the arc on the ring and then carefully sanding the complete inner diameter of the thrower to enlarge it a little, fitting the piece regularly.

After quite some sanding and trial fitting and two ‘hot sessions’ it dropped on!

You can see the reference mark and some burn traces in the bottom part of the picture. I’m not sure if you can make it out on the picture below, but the hard work paid off. Nice fit I think.

Fitting the seating ring and bearing is easy with a press. There is a little bit of room between the bearing and the seating ring. I’m not sure if that is supposed to be there, but I do not want to push too hard with the press on the bearing.

It costs something like € 70,- to galvanise a box of parts. It does not matter if that box has 2 bits or is cramped full. So, I’ve been gathering things to fill the box with, but kind of struggled to get a reasonably filled box. As I do want to finish the rear end of the suspension soonish, the box was delivered to Galvin to process. It should be back here within 2 or 3 weeks or so.

Not sure how I am going to fit the throwers onto the hub though. There is a small edge on the hubs over which the throwers should be ‘clicked’. Obviously I do not want to damage the throwers so I’ll either need to find a way to equalize the pressure over the circumference or heat it up so it sort of drops over it automatically. The edge seems to be smaller at the bottom than at the top, so heating it seems a plausible way to go.

Once I get them back, I’ll give that a try first.

The exhaust headers, thermostat outlet and the flexplate all need to be replaced by specific parts, either specifically made to fit the GD (like the exhaust headers) or modified to fit into the engine bay.

So, the first thing I did was read up on how the thing actually works.

The way I look at it, the drivetrain from engine to the wheel on the road is a divider, where you can control the division factor by selecting gears. Other than the gearbox there are is only one other factor which determines how 1 turn of the engine-output-shaft translates into a movement of the rear wheels.

This is the differential ratio, 3.54 in my case. Once the gear is known, you can calculate how many rotations of the engine it takes to let the wheels rotate once.

How that translates into road-speed and handling, which is what I am ultimately interested in, is a bit more complicated. The size of the (rear) wheels is one thing, their grip on the road and the influence of all sorts of drag are others.

It is pretty easy to create a set of graphs with the above information and the gear ratios of the gearbox. These graphs show you rpm vs (ideal) road-speed and a ’shift behaviour’ graph, which shows the drops in rpm given a shiftpoint. Here’s what that looks like, given a Tremec TKO600 gearbox and 275/40-18 rear wheels.

Obviously this is all theoretical. The speeds will be lower in practice as drag increases with speed and how the ‘dry numbers’ will translate into actual experience is the big surprise I guess. What can be determined from the numbers however, is if the setup of engine,gearbox and differential makes sense overall and helps giving a quick visual overview of the length of the gears, an indication of the effect of the overdrive etc. The second graph above clearly shows the length of the overdrive vs the first 4 gears.

I’ve done this graphing for a couple of gearboxes and stared at the numbers and graphs for a day. Combined with my personal preferences these are the conclusions I came to:

• manual gearbox;
• in the ‘grand touring’ theme I’d like an overdrive in top gear(s) which gives me a cruising speed of around 100 km/h at 2000 rpm;
• ‘open box’, that is, the gearbox needs to be documented and serviceable (by me);

After all that, the choice boiled down for me to a Tremec TKO600 5-speed or the Tremec T56 6-speed (big surprise… not!). Having no hands on experience with either of those two boxes, I spoke to a couple of people having some experience with one or both. Apart from the obvious differences like 5 vs 6 speed and the TKO being a bit stronger on torque allowance, the main thing I distilled from the comments was that the TKO is the more ‘raw’ box, more aggressive perhaps and better suited to track (ab)use, and the T56 being a bit softer and perhaps more suited for cruising.

Making my mind up, I think I’ll opt for the TKO 600. The bigger torque number gives some playing room with the engine, and I think the LS2 has enough torque to already let me skip 2 gears, so why bother with a 6-speed?

No words needed. At the moment I can’t do much to the engine yet, other than drool over it. (Well, I could go mad on polishing I guess)

I went for the el cheapo option on the stand and crane; this showed during assembly. I had to augment the bolt pack inside with quite a few to get the things assembled, but alas it’s there now.

While I was there I noticed a little gadget which seemed perfect to set the camber and castor for the suspension.

It’s capable of doing both absolute and relative angle measurements and has a magnetic base. Sounds perfect in theory. I’ll report back on how the thing works out in practice.

In the end I went for the complete engine package instead of building from bare or short-block. The deals you can get on crate engines these days are so good that building one from scratch is, at least money-wise, absolutely not interesting. I would have liked building one though. Oh well, it’s not as if there are no other jobs to complete.

There is no way this engine goes into the cold and damp garage for now, so the view from behind my desk should considerably improve when the engine arrives.

Spent more or less the weekend reading up on the differences between all the different models of LS engines and their architecture in general. A while ago I bought a book on LS engines because frankly, I dont know much about the LS engines.

Once talking to a representative of one of these companies, he may, or may not know what he is talking about. He will gladly tell you that the product you are looking for may, or may not be in stock and may, or may not fit the application you want to use it for.

When you finally find 2 or 3 models, which may fit the application, their price difference of around € 50 euro’s a piece may, or may not be explained by their specifications. The most expensive one may, or may not last longer than the cheaper model. There may even, or may not be a story behind them which sounds plausible, but can not be checked.

At the point where you have made up your own mind on what UJ you will purchase, the supplier may, or may not sell it directly to you and may, or may not tell you to call a local dealer. Calling this dealer may, or may not put you into contact with a person asking you what the price of the item was the distributor may or may not have promised you.

Once the UJ has been ordered it may or may not arrive tomorrow morning.

The second however, disaster! The first joint went in smoothly but when I pressed in the second the complete “top lid” of one of the caps broke off!!! Aargh. No idea how this happened. I did not subject the joints to excessive force, although using a press sort of hides these forces.

So, after a minute or two of swearing I pressed out the one joint which, thankfully, did not damage the shaft and came out pretty easily. It should just be a matter of purchasing a new UJ now and pressing that in. All in all, the job took me 4 hours where it should have been like 10 minutes.

Then, put the disc and stub onto the stub axle.

Grease up the other bearing and press this one in by hand. Put some more grease on top of the bearing.

Put the D-washer on top and hand-tighten the nut while turning the disc.

While turning the disc, torque up the nut up to 25ftlbs; the disc should still be able to turn albeit with some resistance. Loosen the nut by one flat and put on the locking cap and splitpin. I followed this procedure found at: http://www.bernardembden.com/xjs/hub/index.htm after trying to actually measure the endfloat.

After that, I filled up the cavity with grease, which takes quite a bit of it! The new black caps dont come with a hole, so I drilled one in to be able to let the air out and being able to see when to stop putting grease in! Once it comes out, you’re actually too late already, because it will keep coming out for 5 minutes more.

Everything but the nuts at the end also needs greasing. In the end it’s just doing things in the proper sequence. Start off with one side, grease everything up which needs to go on there and press the shaft a little bit through.

With the help of a dummy shaft, I made sure the fulcrum was aligned properly, so I could gently tap it through the distance tube in the middle. The hardest part is then to position the inner set of 4 rings. Everything is slippery due to the grease and there’s not much room. With some patience it’s doable though. Repeat on the other side and make sure the shaft has an equal protrusion on either side.

The last step is to put the GD brackets on. I was a bit nervous about this step, the holes in these brackets are drilled very accurately and if they would not fit it could mean that my shimming was incorrect and I would have to do that bit all over again (and go through all the washer hell too). However, the fit was perfect! Yay! Keeping my fingers crossed this translates into the proper toe-in too later on!

When assembling with these washers it’s somewhat important to watch the surface friction and make sure the pair of rings stay in their “compressed” state. I do this by sort of overlubricating the contact surface to make sure the surface friction is less than the friction between the rings. After that’s it’s just a matter of torque-ing all ten of them up and taking a picture.

Next step would be to bring the uprights and the hubs together, at which point I realised there were 2 oil seals involved needing a 12 hour soak before assembling. So, that more or less stopped the assembly on this part for today.

And I had them all layed out so neatly…..

Here’s mine, ordered by age:

1. Bugatti Type 57 Atlantic — 1936
2. Mercedes 300 SL Gullwing — 1954
3. Chrevrolet 3×00 (pickup) — 1955
4. Corvette Stingray — 1963 (split rear window version)
5. AC cobra 427 (duh!) — 1965
6. Ford GT 40 Mk I — 1966
7. Landrover Defender — any year
8. Ferrari Dino 206 GT — 1968
9. Jaguar XJ12 Series II — 1973
10. Aston Martin Vanquish — 2001

Runner up:

11. Wiesmann GT MF4 — 2003

Apparently the 80s and 90s didn’t do it for me.

Feel free to add your list as a comment.

After assembly, I noticed that the right side fulcrum shaft was a about a centimeter shorter than the shaft used on the left side ???. After fastening them both the left side didn’t “clamp”, so the longer one is definitely not right. Checking the invoices from the supplier did not show a difference between the shafts. So, I’ll have to contact them about that next week.

The upper wishbone fitting also did not go as planned. While the right side one fits nicely, the left uppper wishbone does not clear the chassis as can be seen in the picture below.

Now, before I start cutting into the chassis, I’m going to chat to some other people on this. It’s not much of a difference and I probably could force fit it, but I want to make sure I’m not doing anything else wrong. The right side is a snug fit, just clearing the chassis.

All in all a bit less than I had planned for today. Oh well.

The other wishbone is even worse, something which I already noticed when fitting the GD brackets to them. I think I’ll have to construct some sort of temporary press to push the wishbone arms a bit apart to be able to fit the right side.

On the other hand, pressing the water deflectors on to the uprights was an easy job, using the press.

I’m running out of nordlock washers, so I’ll order a few next week. Once I have them I can finish the whole front-end I guess. I had planned to do the rear-end first, but I think I’ll create the same wheelbarrow as Andy did.

“It’s been 117 days since my last confession…”

So, perhaps a little status update is in order. Although I declared the garaged finished earlier, there’s always something that needs to be finished/improved. So, this summer we place 2 new windows in the south wall.

Although not a very big job, it always takes more time than originally planned. And yet again, I forgot to take a picture of the finished project!

Blogging wise, time was spent migrating from Blogger.com to a local Wordpress installation. This allows me to use all the server stuff I already have in place in the office anyway and gives me a bit more control over the blog. I also got fed up with google analytics slowing the blog down even further than I do myself with all the pictures.

Wordpress also gives me a couple of extra options which would be harder to do at blogger:

• iphone specific theme;
• support for pages and posts within my ecto blogging client;
• support for both categories and tags;
• more flexible uploads which I’ll need shortly.

I have tried to keep all URLs the same where possible. All feeds and links should still work as they did on Blogger. I had to sacrifice the ‘Followers’ widget and the ‘Profile details’ which are Blogger specific items. There’s some work left to cater for Internet Explorer users (although they should use a better browser anyway).

Work on the cobra has been a bit slow, partly due to the above. All donor parts are basically done and waiting for me to put them on to the chassis. For the front-end I assemble the uprights, at first a bit baffled why the ball joints did not fit.

Using the bench drill and a 1.5 mm cobalt drill, creating the holes is quite easy. Next was turning the differential on its feet and re-determining how many shims were needed to get the brake discs in the centre of the calliper. An easy job, though in the end I came up short one shim, which meant I could only finish one side of the differential build up.

The hardest part of assembling the calliper to the diff is fastening the calliper bolts. They are hard to reach as is, but my torque wrench does not fit either, meaning that fastening them up to their specified value is sort of a guess. I could buy a special piece, but that sounds a bit over the top for just these four bolts. After fastening the two you alse get to lock wire them, which went suprisingly well, considering the location.

So, one side done, once the missing shim arrives, the other side should be pretty quick.

and did a trial fit, only to find out the bracket would not fit. (both of them in fact). In the end I had to put the wishbones under the press and squeeze it a bit to be able to get the bolts in. Let’s call it an ‘engineering fit‘.

I probably should have painted the other holes which are not used; I did not realise it at the time.

Here’s also a detail of the Nord-Lock washers I’m using. As a rule of thumb I’m adding around 20% to the specified torque numbers in the jaguar manual. With the nordlock-washers that should lead to about the same bolt tension.

The steps to get to this are not that hard. Basically what you do is build up the hub around the fulcrum shaft mounted in a vice. In the picture you see the black space tube over which the hub slides down. In the jaguar parts catalog this tube used to be two smaller tubes with the shims between the two tubes. Now, the shims can be placed on either side of the tube.

To determine how many I need, hopefully an even number so I can put the same on either side of the tube, I put a known amount of shimming (on top of the tube in the picture), making sure it is going to lead to a positive endfloat. I just used the original shims plus a couple.

Placing everything on the shaft and filling the end up with some spacers and fastening gives a hub with a measurable endfloat which will be positive. Because I knew how many shims I had put in and I know what it should be, I can calculate what the actual number of shims needs to be.

I’m not sure how accurate this all should be as most of the fellow cobra builders tend to send their hubs to Ward Engineering or equivalent. In the final buildup you’ll need to grease the hell out of the whole fulcrum. I’m also going to use a modern style seal instead of the old 3 piece one. The felt piece in the classic seal feels a bit dated, although jaguar fellows keep telling me it works fine.

You’ve probably noticed I have carefully avoided mentioning the actual measured endfloat and the amount of shims in the above text. This is because I lost the post-it on which I had written those numbers down, and I don’t trust my memory so I have to do the whole thing again. Oh well…

While I was at it, I replaced blogger’s commenting system with the intense debate commenting system. This allows commenting without popping up a new window or reloading the whole thing, plus it allows me to respond to those who take the effort to comment, something which was kinda not possible from within blogger. Let me know what you think!

To make this post also about the cobra build, here’s a picture of a Nord-Lock locking washer:

In relevant places, like the brake callipers, I’ll use these washers in addition to the lock wire. I’m not a big fan of loctite. Lock-wire, as such, looks nice but I’m not convinced it is really up to the job of locking bolts. I do appreciate the beauty of it and its usefulness in keeping parts from flying around if something breaks (or should that be: ‘when something breaks’?) Nordlock has a convincing explanation on how the washers work on their website. One of their customers is Donkervoort and I like their cars a lot!

The new bearing cups arrived today too, pressing them in was a quick job. I got them for free, so good service on the part of Kolvenbach Jaguar there.

I’m still wondering about that por15 stuff. I’ve never seen anything like it. It’s hard to capture the finish in pictures, but perhaps these two give an idea.

Especially in the second picture, the finish almost looks ‘metal-ish’ The spots are the original welding spots. Quite happy with how it turned out.

I also pressed the bearing cups into the front hubs, that is, only the large ones. The smaller bearing actually turned out to be too big! What gives? This bearing comes out of the wheel bearing kit LM258, which contains a Timken LM12711. The old bearing had a LM12710 cup, which has an outer diameter which is about 0.7mm smaller. The inner size of the two is the same, so the roller from the LM258 kit can be used.

Looking at several sources on the internet, I’m not sure what to make of this. I am not 100% sure of the precise year/model of donor I have, but I can not match the smaller cup with a Jag model / year combo, whereas the larger cup is mentioned for several.

Shrug, best get the smaller cup next week and be done with it I guess.

First, with the help of an el cheapo gazebo, I created an improvised spray booth.

This worked much better than expected. After a bit of testing to get the viscosity of the chassis coat right and the spray gun adjusted, spraying the two bike parts was a quick job. The goal was to record the settings for the gun, the amount of solvent to use and, obviously, look at the end result.

The chassis coat, when sprayed, gives a unique finish, more matte than brushed. The breather is no luxury, this stuff is nasty.

The rest of the day was spent masking the jag parts. I’ll probably spent tomorrow completing the masking and re-assembling the bike, so I can get it out of the way (you can just see it behind the tent on the left)

For reference, when you buy this thing at a Jaguar Parts supplier it’ll cost you something like € 130,- (not sure if that would be a new or a used one though) The return-spring and some spacers were not included, so I had to order those separately.

Cleaning the parts and re-assembling was a quick satisfying after dinner job. Like Andy, I too like the clean looks without the plastic handle, perhaps a pressed on piece of stainless steel instead of the plastic?

Had a chat with the guy on painting the parts with chassis coat. Particularly on the surface preparation, “Do I use metal ready or not?” His statement was that the paint would adhere fine to the passivation layer and that any acid-like fluid would ruin it, significantly reducing the corrosion resistance of the part.

Interestingly, asking exactly the same question to a POR15 employee (in the US, not in the NL) he stated roughly the opposite. Metal-ready won’t hurt the passivation layer because it is in so short contact with it. His advice was to use the normal preparation procedure.

That left me with nothing else than to try it out. Took two parts, prepared one by just degreasing it and brushed chassis coat black on it. I prepared the other part by dipping it in metal-ready for like 5-10 minutes or so.

The first thing i noticed is that the passivation layer is gone in 3 seconds; that is the yellowish colour is gone from which i deduce the passivation layer must be gone too, leaving a zinc coloured surface.

I’m writing this on Monday, so the parts have been curing for a couple of days now. Everyday since I painted the parts, I did a little scratch test to see if there was a difference. There is not, as far as i can see. Both parts look the same and the chassis coat adheres well to both. It’s not excellent though, chassis coat is clearly a top coat and not as much a protective coat as POR15, the real thing.

So, this leaves me with one preparation step: painting them. I’m planning to spray them all in one session, so the next days, I’ll be probably busy masking them appropriately and building a spray booth somewhere in the workshop to spray them in.

I started to put in the bearing tracks. The fulcrum ones are relatively easy.

and the stuff is blue! I’m sold.

The n/s handbrake retraction fork seems a bit too long? Might just be the trial assembly, i’ll figure that out later.

One brake pad location was a bit smaller, making it necessary to shave a tiny bit of the pad. Scraping of the greenish paint turned out to be enough.

Having all the parts in place i tried to determine the necessary shimming to get the brake discs into the midlle of the caliper. It’s not quite clear where you should measure these. There are 4 places on the inside of the caliper which seem to be machined though, so i took those.

Being used to metric it means a little bit of converting back and forth but in the end it looks like i need one shim of ‘10 thou’ and one of ‘20 thou’, o/s and n/s respectively. I’ll just order a bunch and see if on finaly assembly these numbers are still the same.

The ring top-leftish in the picture is a placeholder for the one part missing here, a hinge pin for the handbrake. I think it got somehow lost in the galvanizing sink.

After disassembly i turned the diff on its head and tried to determine the shimming for the diff bracket. Without the actual shims available that seemed to be impossible to do. The GD brackets are drilled to “fit original jaguar shimming” whatever that may be. It seems to imply there is ‘one correct shimming arrangement’ here? Would that then directly set toe-in and toe-out properly? Need to read up on that I suppose.

So, there’s a little puzzle ahead on that. I’m not quite sure what the proper shimming order should be to a.) get toe-in/out and other measurements within specs and b.) minimize the number of times i have to lift up the diff (or any other suspension part for that matter).

1. shims behind the brake discs so they’re in the middle of the caliper;
2. shims behind the diff bracket so the GD brackets fit properly;
3. shims behind the drive axle so the camber is within specs.

Sounds about right?

After a while I fabricated a suction device from an old vacuum cleaner. That helped a lot, until the vacuum cleaner decided to short out and smoke a bit.

This morning I gathered all the parts and delivered them to Galvin where I had the hand brake parts treated too. This time the parts will be yellow-passivated, because that will provide a better profile for coatings than the blue passivation. Got some compliments of the guy at the factory, he said the parts he usually got to treat looked a bit different.

It makes the parts almost look like there is a paint finish on them.

I also got my hands on a broken bench drill. It’s a new machine but the motor does not start well. Bit of a gamble, but it sounds like the startup capacitor is either the wrong size or broken. It’s too big for my multimeter so i can not be sure if it is Ok or not.

Opening up the motor itself revealed a loose wire?!? Seconds before the motor ran smooth, so i must have torn it loose on opening up the motor. Other than that, the motor looked fine. I also noticed the motor got quite hot when trying to get it to run, but i’m hoping that is the abnormal load on the secondary coil during the testing. If I can get this fixed by a capacitor replacement, i got a really good deal! If not, i got a lousy one.

Not only was the pinion seal not installed properly, it was completely the wrong seal! On top of that the output shaft seals were also the wrong ones. A previous owner of the diff must have had the same problem as me.

Anyways, all seals replaced now by people who know what they are doing. The new pinion seal properly sits behind the flange now.

While they had the diff in parts I figured they could just as easily give it a spray. I rounded it off by installing the backplate with new stainless bolts and a diff we have!

I might give the base housing another spray, or use some POR chassis coat on it.

Upside is, trying to give a optimistic swing to it, I now have one less hub to clean.

Using the rivnut tool i bought a while ago, the little covers were repaired with a new rivnut and although i still am missing a bolt and some locking thingies, assembling the caliper was pretty rewarding.

I’m not sure about the inside, the clip i have seems different than what i can find in my manuals. Also the spring on the right seems to be in the middle of the path were the missing bolt should go to hold the covers.

The other caliper should not be a problem.

The galvanising was sort of an experiment; i found a company nearby which asks a flat rate for any ‘box full of metal parts’. They galvanise with blue and yellow finish (blue-ish and yellow-ish i guess). I asked what the limit was for the parts, but they didn’t give me one, so perhaps i should bring the whole set of suspension parts too?

The UK has a system to allow people to build their cars and drive them on the public road. The Single Vehicle Approval is key to this system and issues the approval to the owner to legally use the self built car on the roads. The Association of Car Enthusiasts has been tracking the legislation related to modified cars and kitcars since 2004. Their latest news is about the ‘Loss of the SVA test`. The SVA is an important, if not the most important, component in this legislation and the prospect of it changing affects everyone modifying a car or building one.

The only ‘fact’ i can distil at this moment is that the SVA will be replaced by the IVA (where ‘I’ is for Individual). What this IVA is exactly and what the differences are with the current SVA is, as of yet, unclear to me.

Needless to say this potentially has a major impact on kitcar builders. The cars are usually a major expense for people and often worked on for many years before they are allowed on the road. The prospect of not being able to put the Cobra on the road after having worked on it for a long time is sickening.

A short talk with the guy at the excellent Rustbuster shop quickly convinced me that MIG was the better option for my skill level; beginner, not to mention my wallet. A good TIG machine costs the world. After trying a few welds in their training room I went for the Cebora Bravo 155 machine. This was one of the rare occasions where i spent less money than originally envisioned. I am going to attend some welding course when time permits.

While the cracked housing is bad, that didn’t explain the earth leakage. Opening up the motor itself did though:

That’s fried! I’m hesitant to just put another motor back in. I’m thinking of turning the whole compressor in and getting one back with a little more grunt and running on 3 phase current

Here’s roughly how it looked before we started:

Here’s the best comparison I could find for the outside view. Apparently we did not take a picture once everything was done, odd.

This shows much better what it was all about:

Next to that, inspecting the donor parts in detail reveals some things which need some attention. The parts are mostly in good condition, but obviously show their age and use.

One of the parts showed a worn (broken ?) inner wall. The other shaft had problems too but those I managed to repair to satisfaction. This one will have to be replaced.

It’s not trivial to make a good rivet I found out. The first thing you have to get right is the amount of shrinkage you want to introduce in the rivet. Too little and the rivet is loose, too much and it deforms too much.

The next thing to be aware of (at least in the aluminium rivets I bought for practice) is the speed at which you ‘rivet’. Slow is the thing, apparently. If you go to fast the threads will be ruined. I’m waiting for delivery of the steel rivets to be used for attaching the brake-lines to the chassis.

I started with putting all nuts and bolts from the chassis kit loosely in place. This is to see if i got them all, but also thinking that their destination is probably the best place to keep them instead of in a drawer somewhere.

Next up was getting some (more?) wax into the inside of the chassis. Finding a small enough applicator which would also fit the venturi attached to the compressor turned out impossible, so one throwaway aerosol it is then. An easy 15 minute job with nothing to show for. I needed some more…

Still somewhat hindered by the thought of not doing things in order for the build I instead created a storage place for the bottom plates of the car-lift.

While a useful end result, I realised I was just making up excuses and needed a ‘real job’, so, I decided to do the front-brake-pipe run. Here’s the end result:

Gave me good pair of sore thumbs. I can’t attach the p-clips to the chassis yet, as i want to use the same rivets as GD has been using, but I do not have such a rivet gun yet. I feel another tool purchase coming up next week

I should probably stick to the proper order and first finish revising all the jaguar bits, but it’s very tempting to start putting things on the chassis. M.u.s.t. r.e.s.i.s.t….

Enough said…

Saturday was mostly spent at the Bruntingthorpe Proving Ground where a little circuit was available for the GD car owners to race their cars on and for people like myself to take a ride-along. Lots of goodies, like a very nicely done T70:

The Arial atom exoskeleton cars which the event organiser, Big Thunder was using:

And obviously, quite a few GD427’s

I had a ride along in both a GD427 (thanks Hein!) and Andy drove me around the circuit in their T70 demonstrator:

Sunday, we spent a day in Cambridge. Also nice, but erm.. different

GD is having an Open Day next weekend. As my chassis is probably in the jig right now i thought it would be nice to visit them. Combined with a small trip through the UK, sounds like a nice little holiday.

I hope I can get a look at my chassis there and shoot some pictures of it. Obviously the planned ‘ride-along’ in the GD427 is something i look forward too also.

The Garage is more or less ‘done’, just planning for some racedeck stuff on the floor a bit later

Oh, this is not how it actually looks at the moment (it’s full of stuff again), but for rembering how it looks empty and clean and all…

That is, finishing up the garage. Next monday the new cement floor will be ‘poured in’.

Now, on replacing the seal, you don’t want to collapse that spacer any further or you’ll need to rework the whole diff, which is definitely something I want to avoid. To be able to replace the seal properly there are a couple of methods documented in manuals and on the internet. Some describe measuring the force needed to turn the pinion through its backlash and aiming to get that back after replacing the seal. Most of them make a note of punching the nut, pinion and flange to be able to return the nut into the exact same position, also by counting the number of threads sticking out the end of the nut.

1. the seal i have differs from the one coming out; not sure how it affects the procedures, but it seems less ‘thick’
2. the original nut was erm… completely loose, as in, I could manually undo it from the pinion, so returning it to the exact same position was not possible. I tried fastening the original nut and gave the count of threads a go, fully realizing it was next to useless.

For now, i’m going to leave it as is and continue with the other part of diff reconditioning: repainting it.

Some careful sawing and using a vice to hold the puller slowly released the last bits from the pivot shaft.

Yay!
On the other hand, trying to pull the stub axle from its carrier broke my puller:

All the donor parts are now disassembled, so the reconditioning of the diff is next. I ordered the gasket and a replacement pinion seal, let’s hope that is all that is needed.

1. Marine Clean; get rid of dirt and grease (i doubt there is any left after the soda-soak they all got, but i’m following instructions here)
2. Metal Ready; acid plus zinc-phosphate to get the metal ready to receive the real thing;
3. POR15; the coat that is going to protect the parts from rust;
4. Chassis Black; the coat that is going to protect the POR15 from UV light; as far as there will be any under the car. (and yes, i got a bit more than just that tiny can there)

Along the way most time is consumed by things which are stuck, but need to be loosened. Yesterday i spent a whole day grinding a wishbone from its subframe because tapping-it-out was undoable. Here’s another example, as of yet unsolved, of something which is stuck. Suggestions are welcome. I’m thinking of putting it into the oven or use a mini flame thrower on it.

Also had a quick look at the differential. Although it was said to be 100% in order, i’m hesitant not to check and recondition it. There’s at least the pinion seal which is leaking and the paint isn’t covering the whole diff. So, this will need some work.

The differential also seems to be the most logical place to start the actual build with, that is, the first part to prepare and finish before assembly starts.

Next thing to try was to get more contact surface on the electrode. Demolished an old trowel and replaced one of the bars with it. Now, that did the trick! Lots of bubbles and I was actually afraid to put my hand into the bath. It went so well, the battery charger died after 3 hours or so: overheated. Putting the old PC power supply back into place (including the CD player) and left it for the night.

Good morning:

Someone pointed electrolysis out to me recently as an alternative and that brought back some memories from school chemistry class. So, I quickly constructed a test electrolysis bath from some old steel pins donated to me by the contractor doing the garage, some rings to hold these pins attached to the bath, an old ATX power supply, water and a bag of washing soda. It looks something like this:

Fill up the tub with water, put in the soda, attach the +12V lead to the steel pins at the outside and the other end to the bit we’re trying to de-rust. Then, flip the switch, sit back and wait.

Here’s the before picture of my testpiece as removed from the front axle:

The local garage, Autobedrijf Bartelen, was kind enough to lend me a puller for the stubborn rear hub:

Apparently the thing was so tight it scraped some of the metal into a rim. Obviously, that has to be removed again later on, hmm will that be a problem on reassembly?
I’m still suppressing thoughts on the remaining two joints….

The axles are horrid as usual, but i trust they will clean up nicely when i’m done with them.

Man, these things are heavy.

1. a GM 5.7 liter v8
2. a limited slip differential of ratio 3.54 or 3.31

Not much to do but wait until it’s done.

I’m going for a visit to Speedon tomorrow; visit their new location and hopefully get a step further in planning out the project.

Next up is the outer wall.

That is, taking a picture of some stupid mistake I made to explain it to someone who actually knows what he is doing and help me out. Also, good excuse to fiddle with mirrors taking a picture of the camera with the camera

What you see there is an AC Cobra Replica, Gardner Douglas style. This car is a replica of a 60’s sports car originally manufactured by the British ‘AC Cars’ , but made famous when Carroll Shelby got his hands on it to combine it with an American V8 Engine.
The first phase to building a car apparently is to spend countless hours browsing the internet to get a grip on costs, supplier info and the differences of all the offerings. Especially in the beginning of this process, it is easy to lose whole weekends just doing that.
Two things stood out in this search process as being more important than any supplier info:

1. talking to people who have already built one;
2. reading the excellent build logs of other people who are building.

Anyways, enjoy!

marcel

At the end of the second day however, first beginnings of the new inner wall are there! We’re getting a real door too.

The part on the left is the air filter / reducer, right is the oil dispenser. I created two outlets, one after just the air filter and one after the oil dispenser. That way i can use compressed air with oil (for rotating tools etc. which need lubrication) by hooking up at the end. By connecting in the middle it will just be clean air without the oil; I gathered that for spraying paint oil is the last thing you want in the air flow, but i have not much experience with these tools.