Good bye Locost 7 Hello GT40!!

[Dave P]

Hi Everyone:

Today is build day number one for me on my GT40. I have decided to do a scratch build for my 40. I started a Locost 7 a while back but lost interest in it after hearing one at track day back in October last year.
I have always loved the sound of built V-8 and I knew a 4 cylinder was not going to satisfy my itch. I love have always loved Fords and a the GT40 is the one desire I thought was out of reach but after lurking here for a while and hours of reading old threads. I feel this is a project that I can do.
There are members of this forum that have already been of great help in getting started on the right track. Thanks to you all!

I'll be posting photos on this thread as often as I can.
Best Regards Dave epper:

 

[Russ Noble]

Great stuff Dave.

Good to see another scratchbuilder here. I shall look forward to watching your progress. Good luck with the build.

Cheers

 

[Jac Mac]

This GT40 should not be lacking in the Brake department

You could always build the locost as an 8. rather than 7. that should fix the sound issue, possibly create a few 'new' issues, but they would be fun to deal with.

Good Luck.

Jac Mac

 

[John Milmont]

I hear of a lot of people putting s2000 engines in those, those don't sound to bad when their spinning around 9000rpm! What engine were you going to put in it?

 

[Russ Noble]

You could always build the locost as an 8. rather than 7. that should fix the sound issue, possibly create a few 'new' issues, but they would be fun to deal with.

Good Luck.

Jac Mac

There's a guy in Christchurch who's put an alloy Rover V8 ( Improved Buick 215 for you Yanks) in a Locost. Very nice too. And of course there's the Westfield Seight. You could always fit an alloy 454 Windsor and see how much the chassis would twist.... It'd be a good combo but it's no GT40....

 

[Dave P]

Guys as far as brakes I got that covered it will be AP 4 piston calipers
all around. Will use be using 1 1/4" x 12.19" 8 bolt 7" J-hook rotors in the front and 1 1/4" x 11 3/4" in the rear. Ferodo DS2500 will be the pads
AP master cylinders.

I know that I could of had a V-8 Locost but if your heart is not in it why do it. You just cannot get past the GT40 on the wow scale. I have been around Charlotte for about three years and can count on one hand how many Ford GTs and GT40s I have seen. That don't include the half finished ones at Holman automotive.
Regards Dave

 

[Dave P]

2-7-08

The pile of long steel tubing is slowly becoming a pile of short steel tubes.
(measure twice cut once) Anybody got a tubing stretcher?

I have realized that I have to replace some fabrication tools that I gave away when I quit racing years ago. A friend has located a 70's 302 complete engine for $150.00. It also looks like I have located a Audi 5000 transaxel also. Tubing so far was less than $300.00 including tubing for my jig. My windsheild is on order and roof spider and side pods also.

Progress

 

[Dave P]

2/22/08

Started welding together chassis jig today. I made a good investment a couple of months ago. It was a smart level made leveling the jig a breeze.
Also shipped out the last of the body panels I had for the Locost 7. Ebay is a wonderful thing.epper:

 

[Dave P]

Hi All:

For the front of the 40 I have chosen to go with 12.19" x 1 1/4" 8 bolt on a 7" bolt circle rotors.

 

[Dave P]

Here is my starting point with tubing

2" x 3" x 3/16" wall for chassis jig Thanks to Russ Noble for helping me get these pics up Cheers Dave

 

[Dave P]

More welding on chassis jig today. Should be done on Monday.

 

[Dave P]

Hi Everyone:

I went to the engine builder today to ask some questions. I was left confused . I was thinking a 302 but he says I should go for cubic inches and torque with a stroker kit. Could any of you that are using a stroker comment? I will Track day it once in a while and drive it a couple times a week. Thanks Dave

 

[Russ Noble]

Dave,

If motor was the only consideration I'd stroke it every time.

But in a 40 you have to consider the trans in the equation and how you're going to drive it. If you're running a lighter trans such as an Audi in stock form, you may be better off without the extra torque. If you're going to give it heaps then you'll need a ZF or a Porsche G50 or 930 and a stroked 302 won't be a problem for these.

Cheers

 

[Jac Mac]

If using the 302 8.200" block as a basis use the 3.25" stroke /5.4" rod combo if you want to run up round 7000 plus with solid cam. If your going to run a hydraulic cam then you could try the 3.40" stroke/5.40" rod deal-not my favorite though.

A plain 3.00" stroke/5.625" rod/1.070" piston would sound grouse at 8000, valve train would cost $$$!

Jac Mac

 

[Dave P]

Started tack welding and fitting some chassis pieces together today. I used chassis jig to clamp and tack the side pod portions of the chassis.

 

[Dave P]

After the side pods were tacked together I clamped the side pods in postion on the jig. I laid the front snout portion of the chassis in place to get an idea of available leg room. I have opted for a tapered foot box area simular to the KVA chassis but my lower frame rail is 3" x 1" x.125 wall tube. I only have a few more days to use the welder here at work as we are getting ready to install my last fabrication project our brake dyno.

 

[Chris Duncan]

Your chassis will have less warp if you anchor your jig to the floor. What happens with a light jig like you have is it has no torsional rigidity unless you anchor it. You can get the chassis all perfectly straight while it's tacked but with the heat of the full final welds it will twist.

If you look at some of the pro builders they have a monolithic jig table that can't warp.

Also realize that you will get some warpage no matter how ridid the clamp down is during welding. It will be "sprung" at least a little no matter what, so if you anticipate this you're better off. If it's an unacceptable amount you can jack it straight if you have some anchors in your slab. Minor tweaking will not hurt mild steel.

One thing you should do is have all the tubes already final welded before you weld any of the suspension brackets. That way you can place the brackets for optimum alignment no matter where the frame rails end up.

For example it's acceptable to have up to 1/4" warpage in the main chassis rails but it's not acceptable to have that same 1/4" innacuracy at the suspension mounts.

You can also minimize chassis warpage by welding in a strategic order (I call it the diagonal opposite method) but it sounds like you already have some racing building experience so you may already know this.

 

[Dave P]

Hi Kalun:

Thanks for your input.
You are correct that a surface plate is a much better way of manufacturing a tubular chassis. The cost of a surface plate is not in my budget so here we go. Besides I figured that the jig I have constructed would be better than the plywood ones guys are using for their Locost 7 projects. Russ Noble had also shared that his chassis had moved a little also.
Over the years on our oval track cars the thing that escaped a lot of the guys when setting up their cars was making sure the car was squared.

Cheers Dave

 

[Dave P]

Chassis is progressing nicely. I cut the last of 2 lengths of 1 1/2" X 1 1/2" tubing yesterday. Lower chassis rail used 1 full length of 3" x 1"rectangle tubing. All that is left is 1" x 1" for bracing. It looks like one more length of 1 1/2" should do.

The Audi 5000 Transaxel arrived today also it looks to be in good order.
Life is Good :thumbsup: Has any one done a center of car rod linkage shifter with the Audi Trans?

 

[Dave Gilling]

This GT40 should not be lacking in the Brake department

You could always build the locost as an 8. rather than 7. that should fix the sound issue, possibly create a few 'new' issues, but they would be fun to deal with.

Good Luck.

Jac Mac

How about a v10 viper powered viento :shocked: