GT-Forte GTs40 build

This is mostly front uprights for which the whole point is to avoid the terrible geometry because everyone either uses Granada or has come from Granada. Mine will have between +5mm and -5mm scrub (adjustable) rather than the 100mm with Granada geometry.

At the back I could just angle the bracket, would be easier but seeing as I'm already making up front arms (as they need to be 100mm longer to account for the difference in scrub) an extra set of arms for the back with spherical bearings isn't the end of the world.
 
I probably should update this more than once a year... ;)

So where are we. First lets address Morton's concern about the bolts for the bearings.
There is plenty of clearance



So bearing adaptors are done.


I made up new rear arms with a spherical bearing inner and adjustable toe


Toe adjusters


And of course painted up with the bearings in


Rear calipers to go with. They will need adaptors though.



I'm not 100% sure if the HiSpec will be quite enough for the handbrake, I've left both sides on the rear uprights so that a second set of dedicated handbrake calipers is an option if not.

So with that I mocked up the rear suspension so I could cut the hole in the panel for the lower radius arm.
 
Onto other stuff.

Fitted the floor. About 1800 holes drilled! That's ~450 3mm pilot holes in the floor.



~450 3mm holes drilled through into the chassis, ~450 4mm holes (and a sea of clecos)



and then finally ~450 4.8mm holes!

Then PU adhesive and rivet it all in place.



I advise purchase of an electric or air "caulk" gun. I nearly crippled myself doing it with the manual gun (and bent it!)

I bought an air gun but it's a bugger to seal well enough to the tubes to prevent it from just getting air leaks. As I've still got a load to do (and then all the seam sealing as well) I'm considering getting the Ryobi ONE+ Caulking Gun.
 
With the floor in place I tested I could actually feed the anti-submarine portion of the straps through the bracing I'd welded in.



Then on to some interior panelling.

Rear (upper rivets left for now as the upper panel will overlap)


left - 4mm


The upper row of rivets are 4.8mm countersunk, 4.8 because they're the smallest countersunk I could find. Countersunk because of the square edge to the sill, I've got some rounded trim to fit to ensure it passes the IVA edge radius tests but unless I use countersunk rivets I'd have to dimple the reverse side of it to ensure the rivet head clearance!

Right hand side, note the flanges at the top and on the floor (and also the csk rivets towards the front), it'll make more sense in a second. Hole in rear bulk head is for the gearchange.


Gear change cover


I mentioned the trim piece. Here it is on the right. Although the left is full length, the right is shorter because of the gear linkage cover.


The cover is removable with a load of M5 button head screws. These will be covered with a pad like the originals.
 
More panelling.

Outer sill panels. Right side (left done as well but not photographed it).


Then the front right of the car.


The rest of the nose panelling is done but the centre panels don't fit with them in place so they're still cleco'd on.
 
Some while back I had a think about the roll cage. In theory given how flimsy the "A" pillars are a roll cage is a good thing in a GT40.

The issue though is that it makes a helmet mandatory. I had a sit in and see where my head could hit and I could easily clout it on the "centre" bar and it wouldn't take much slack in the belts to be able to hit the front bar. The padding you can get for roll cages is pretty much either stuff designed to be used with a helmet (so bloody hard still and not much use without one) or comfort foam which doesn't do a fat lot.

I decided that as it was predominately going to be a road car a cage was more of a risk than a safety feature...but I wanted the option down the line to use one. A bit of experimentation showed that it was not possible to fit the roll cage with the spider in place *and* the stubs were still potentially in the way of my head. I'm pretty certain that the screen would break if you tried to remove and re-fit the spider so there is not much chance of it being an "in and out in an hour job", it would either be fit it or don't.

Anyway, long story short. I decided to not fit it but leave the option there for later. I cut off the stubs and welded in a "box" with 8 weld nuts in


This protruded minimally from the rear bulk head as well as being far "back" and at the very top of the car that the chances of of hitting are slim.



To put that into context with the window etc


I'll make a cover for the top as well which will blend it in more.

Now for a roll cage to go in it's still going to have to be a multi-part and the dash would have to be cut to fit but it's now possible to fit one in without having to remove the spider.
 
So I've realised I've just shown the tops of my seat shells without mentioning them or showing any of the rest of them... :)

Have a photo of rest of it.



Obviously they'll need to be upholstered, for now I've got some closed cell foam stuck together to give me a rough idea (and also something to sit on when in the car!)


Given how thin the foam is it's surprisingly comfortable!
 
That looks to be coming on really well.
Really like the new suspension, need to have a look at some new suspension myself, but it will be an “off the shelf” set up as I know my limitations!
As for the roll cage, I came to the same conclusion. Also I think Frank Catt lost a friend to the roll cage in a GT40. He posted a thread about it, and that made my mind up.
And yes, with workmanship like that on show, an update more than once a year would appreciated!!! ;)
 
As for the roll cage, I came to the same conclusion. Also I think Frank Catt lost a friend to the roll cage in a GT40. He posted a thread about it, and that made my mind up.
I think it was that same thread that made me re-consider it. For track use they're a good idea but IMO makes a helmet mandatory and that would be a royal pain for a road car. I know these cars are hardly "safe" but there is no point making them more dangerous than they already are.
 
Still some updates to go! :)

Tunnel (oh and front bulkhead :) )


The left side of the tunnel has a removable panel to allow the brake, clutch lines and throttle cable to be accessible, the rest will go in one "pack" in the centre and slid in from the back. I'm hoping to never need to access them again but if I do they'll equally have to come out all together.
 
Some more stuff, in no particular order.

Fuel filler close off panel



Fake ribs for the sill tops and access port for the fuel senders


Mounts for the air-con/heater unit.

 
Lots of other stuff I've been working on, not much GT40 building happened over winter but now it's spring (even if the weather isn't very spring-like) I really want to crack on. I did do a bit though.

Changed the Corsa B for an Agila A steering column. Light, smaller and has a clutch so assistance is optional.

Corsa B on top, Agila A at bottom



3D printed a test bracket to make sure it fit



Then cut the dash


Trial fit


New bracket. Fairly substantial as it needs to take the torque reaction from the EPAS.



Original Agila A wheel which should be nice and IVA friendly (currently missing the rear plastic and horn buttons, although I'll have to fill the space where the airbag would have sat anyway)


The steering lock works, there are no modifications at all to the column. As well as a functional steering lock it is collapsible (as is the wheel).

I'm not sure what the spline is on the end of the column itself but the UJ is a 5/8" x 36 spline. Should be fairly trivial to get either a double ended 5/8" splined bar and a 9/16" to 5/8" UJ or a 5/8" spline to 9/16" spline to the 9/16" x 36 of the rack. My only real concern is my angles aren't the same which may some fun with phasing the column.

I've got a cowl which I'll see if it'll cut down and get to work but if not I'll cut down the stalk mounts as the stalks won't fit anyway.

Then I cut a load more holes in the dash


Trial fit of the important bits. :D





Then some switches
 
Bought a set of barrel adjusters for the handbrake cables and drilled a piece of bar to take them.


Welded up a few pieces of flat bar to make a clevis



Cleaned up and attached to the handbrake.



Handbrake in rough position.



I'll solder the cables into the adjusters (I sincerely doubt the IVA inspectors would like those little clamp screws!) but I'll need to work out where they need to sit first.
 
Lots of work has happened, not many updates.

After much consideration around how to do them I sorted the hinges both sides.
They consist of a 15mm bearing block with a bronze top hat bush in on bolted to a section of angle.



The angled plates bolt through over-large holes (13mm as that's the largest my hand drill will cope with!) to a plate with two weldnuts. This allows fore/aft and side to side adjustment but with the plate both allows it to be tightened without a spanner/socket into the inaccessible areas but also clamps things firmly.



I've hopefully got the vertical alignment sorted already but it can be changed by either shimming under the bracket, slotting the holes for the bearings or shimming under the bushes.



Then they came off again and I rounded the corners and painted them.
 
Painted my rear uprights after the modifications for the Audi bearings.



Test fitted the disc and calipers...

Hmmm, I knew it wouldn't fit without an adaptor but it's really close.



After a bit of consideration on making up the adaptor and I started to consider if it was worth it. I was only ~5mm out so if I lost 12mm off the diameter (and that still leaves me with 300mm disks) I could save having to make an adaptor and I could always make up an adaptor later.

So as I have a lathe...



Brake calipers now fit a treat.

 
Hi Bud,

Great progress.

I'm hoping to nail my hand brake set up this weekend along with a score of other jobs after the arrival of lots of new parts etc. One job will be to finally get that pedal box bolted down for the last time.

Talk soon.



Nick.
 
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