Rear brakes are HiSpec Rear SVA Billet Universal Lug (140mm PCD) Calipers
Disks are 312mm x 25mm vented. As fitted to the Audi A6 2.5TDI (for a number of reasons which I will clarify elsewhere).
Monthly Archives: September 2017
Handbrake lever
As ever, not totally happy with the original kit design so modified it (I swear I’d have completed this car already if I didn’t keep thinking similar).
Original
Working out where I want it.
And then new mounts welded in.
Each one of those brackets consists of 4 parts… a ridiculous amount of effort! But now the lower pivot of the lever goes no lower than the bottom of the rails that make up the “tunnel”.
Then welded in a piece of steel to mount the cables into.
The handbrake cables which I bought from HiSpec with the calipers will then just slot into these.
The only issue here is that the handbrake is not central and would pull them to one side. I need to think about this some more.
Tanks
The original GT40 had bladder type tanks inside the sills. These are an absolute fortune to buy and need regular replacement. The space frame replicas both don’t have this area and I’m not going to be racing this there is no need so it’s normal tanks.
Myself and a few like-minded GT40 builders decided that the very best way was to get someone to make up a batch of tanks. That way we could just pay fabrication + material costs and get a bulk discount.
A shot while later we each got two tanks, one for each side.
As these are very long they’re baffled inside
plus (although you can’t see it) there is a trap door at the end to try and keep all the fuel running away under braking/descents. There will also be a decent sized swirl pot with lift pumps as well so it should be ok.
The tanks have the obvious fill port, two vents (one each end), one feed and one return. Fittings are all AN.
There was only one issue now. How to mount them. In the end I went for stainless straps, 4 per tank. These are utter overkill. Consisting of 2 parts each with 5 different types. Two front ends, two rear ends (mirrors of each) and the middle straps.
These pivot at the bottom on mounts welded to the frame
At the top they bolt into top hat adaptors which are fitted through the chassis and tacked onto the back.
Fuel sender access
I got a load of 2mm plates cut to the ATL blank 4″x6″ size.
Sold most on ebay which left me with the remaining ones “free”. 
These were then attached with countersunk rivnuts to the sills
I added some washers behind the rivnuts as the countersinking left the panels a little bit thin.
I’ve not bothered to cut “through” although the centres are drilled for if I want to.
Bonus points for spotting a school boy error here though. 
Finally a picture of the sill with them (and fake ribs) in place
Roll cage delete
My kit came with a roll cage. After a lot of thought however I decided to remove it.
A roll cage is a good thing in a GT40 as the A pillars are almost non-existent. I’ve heard tales of GT40-inexperienced passengers cracking the screen by using the A pillar to grab on to.
There is a big but here. Only if you are religious about wearing a helmet. Even a minor bump without one could result in “life changing” head injuries. There is next to no clearance in the GT40 and I personally felt the risk of hitting the roll cage in a minor bump was higher than the roll cage saving you (on the road).
There was only one issue however. I’m likely to want a cage in at some point if (when) I take it on track which is some what of an issue as even with the roll cage “removed” the stubs on the roll-over bar remain and are pretty much just as bad.
Plus it’s actually impossible to fit the roll cage without removing the spider and (almost certainly) impossible to remove the spider without breaking the windscreen.
A lot of thought later and I had a solution. First I cut off the stubs.
Then I took two identical strips, drilled 8 holes through both and welded in weld nuts to the back.
This was then welded onto the roll-over bar part of the roll cage to give this
The rear bulkhead was then trimmed round it. Now it protrudes but only very slightly.
With the window cut out it looks like this
I’ll put a bit of a cover over it however to blend it in more.
This will let me bolt in a cage if I want (I’ll have to be two part still) without removing the spider and without leaving the dangerous stubs.
Gearchange part 2 (the mechanism)
So, with the gearlever in place it was time to think about how things would get from the lever to the gearbox. A bit of a play with some bar seemed to indicate a rod shift was just possible.
Albeit mightily tight
So I made up a bracket with a bush and welded it to the chassis
Now, I just needed to work out how to get it the rod here (the pointy ended one) link through to the other side of the gearbox.
That can wait until the gearbox is back in however.
Electrics #1
Nothing doing here, just some photos of the bits.
Warning lights and switches
I’ve also got some switch guards. Not got a photo of mine but they are like this:
Water temp / Fuel Gauge / Oil Pressure
Tacho (out of a Superformance GT40 again)
Speedo (0-200mph of course)
Engine mounts (chassis side)
With the engine side of the brackets sorted I took advantage that the kit manufacturer did gearbox brackets. The saved me that job at least.
Shockingly I have no photos of them. The best I can manage is this which shows my attempt at seeing if a rod change might work.
Anyway, with the gearbox in place and the engine centralised in the engine bay with the sump level with the bottom of the chassis I could think about the chassis side brackets.
First off I measured the distance between the bracket and the top of the chassis. Then I removed the engine, measured that far down the horizontal mount locations, then added the thickness of the rubber bushes + 3mm. I clamped a piece of angle in place, drilled through and bolted it up.
This now left me an angled plate a set distance from the bracket.
Then use of special tool #2342
Then drill the hole and trial fit with the bush.
Hmm, not much metal at the end there….
Fear not more metal welded in and we end up with a bracket looking something like this.
To which the mounts fit like this
The tiny 6mm holes I’d drilled for temp location were then drilled out to 10.5mm with M10 weld nuts fitted to the brackets and extra bracing welded on too (no photos again of that, sorry).
Gearchange part 1 (the lever)
In an original GT40 the lever sits on the right sill. This was largely “because race car” but for valid engineering reasons as well.
At first I was going to put in a centre shift because I’m used to a centre shift but then I thought about it some more and reconsidered. I looked at a number of options, mostly cable actuated.
Then one of the group of builders said he was going to get a replica of the original gear-lever setup made…
So this needed mounting. Much sitting in the car was done before selecting the position where the lever “felt” best. Far enough from the wheel to not be in the way but close enough to enable a short reach to change gear. Roughly as well where the originals sat.
I welded in some square tube on to the chassis with some rivnuts to bolt it to.
These then have holes drilled large enough for the rivnut flange in the side panel so that the gearchange sits flush against the side panel.
Seats
My previous update had a few photos of the seats so I figured I should probably put an update on them!
The seats had a long and convoluted journey.
At first I planned to just buy some Inatrim GT40 seats (http://www.intatrim.co.uk/gt40.html). Then I sat in them and realised they didn’t fit. I’m very broad in the shoulders and the “wings” dug into my shoulders. I was uncomfortable in seconds. So back to the drawing board.
The seats in a GT40 are incredibly narrow (450mm or less) and laid back which eliminated almost all the “off the shelf” options. So the first thing was a CAD model. That’s Cardboard Aided Design ( © “Project Binky” ) 
The cat was fairly happy with the cardboard seat but I wasn’t quite so keen.
I followed the cardboard seat with a fibreboard mock up. It’s pretty much just extra stiff card.
And of course then sat it in the car.
The next stage was something with more structural strength. A 1mm steel mock up. Still trying to get the general dimensions nailed here rather than looking pretty or anything. Steel being chosen because it’s very easy to just tack together and just grind the welds off to change things.
The steel mock up went through a few iterations. Losing height from this
to this
The seat base equally went through plenty of revisions. From the initial version through this.
and then finally settling on this. Shown here being tested with the belts.
Then when I was happy I chucked the mock up out…well actually I cut it apart and re-used the bits!
Then I started to make the seats properly in aluminium. I’d decided that the seats will be fixed like the originals. Although a metal base not ribbing. I also decided that the best way to do the seat backs was to have them pivot at the base. That way the space behind them can be utilised/accessed.
First off the base, this was in two pieces. A flat section.
then a formed section
And finally the back
The back is hinged and bolted to the rear bulkhead. I considered some kind of quick release (and I may still do so) but felt bolting was best for now. There is btw no seat adjustment. You either fit or you don’t.
I welded in some strip to the rear bulkhead so that it could bolt to it.
Then of course repeat for the passenger side. So the seats look something like this at the moment.
They will of course be trimmed but that will happen later. I also need to make up some headrests for them.