Things you may (not) put into a GT40 body&chassis

Hello everybody,

I am planning to have a GT40 as a self birthday present in sep. 2003.

I live in a small town were the garage stores are few, and were custom or modified parts are not easy to get too. There is also the fact that I am not particulary interested in high performance, (I actually drive a 230 hp car and not planning to go much higher), so I won´t need to use expensive parts as porsche tranaxles that lead into more expensive parts that leads….

For this and other good reasons I am thinking of using a donor car and go as far as I can with it (at least I would know that all the parts I need should come inside)

What do you think of using a 95’ Mustang as a donor car. Will I have any problems? As far as I know the GT40 kits usually come with just some grade of freedom for the things you can put into it.

I have a Subaru Impreza 2.2 turbo, could I use it too?. (IMSA would have a heart attack!)

Thank you all for you light on this issue.

Javier

 

[Mark Worthington]

Javier,

First, congratulations on your decision to build a GT40.

Regarding donor parts, the manufacturers of GT40 kits that are worth having are quite unlike, say, the FFR Cobra kit in that they don't use the "donor car" approach. Sure, they use a small-block Ford engine which can come fram many sources, including a "donor car", but that's about the only thing you could pull out of a Mustang and drop into a GT40. Well, maybe the radiator too. I do know that GT40 Australia's GT40 kit uses some Corvette C4 suspension pieces and brakes too, I think. But again, that's it. So if you wish to start with a rolling chassis, you could use an engine from a Mustang, a transaxle from a Porsche, and brakes and suspension from a Corvette. But you won't find any one "donor car" that can supply very many of your parts.

I recall from your other post that you said you don't have much mechanical experience. If that is indeed the case, I think your best bet may be to purchase a complete kit or a turnkey car, so you don't have to scrounge for and fabricate parts. As those options can be expensive, you may want to shop around in the UK for a used or unfinished GTD or Tornado...I've seen them reasonable priced and much of the work has already been done for you. Good luck.

 

Thanks Mark,
You are right: the combination ford/porsche/corvette undoubtely results in an excellent car. Like anyone here with a good knowlegde, I think you used “the performance aproach”. The thing is that I would go for the “easy to build/maintain aproach”...
I like to think all the mechanical parts in a car as a team that work together in a way that gives you the best reasonably performance, so I must think that the Mustang gearbox is the one that works with the Mustang engine the finest way and so on. Surely you can put in a Porsche and it would be better but that does not invalid my “team theory” Does it? The bottom line for my question is what would happen if you use all the mechanical parts of a mustang inside a gt40? Will the hole thing blow up the minute you turn the key? Are there any room restrictions that make you use different parts from different models?

Regards,

Javier

 

[Mark Worthington]

Javier, your team analogy is great, but they all have to be playing the same sport! Lets take your Mustang example for a moment and look at the gearbox in particular. The GT40 is a mid-engine car, with the engine mounted directly behind the cockpit, while the mustang is a front-engine car with the gearbox bolted directly to the engine and connected to the differential by a drive shaft which is approximately five feet (excuse the non-metric units) long. The GT40 gearbox must be compact and designed in such a way that the gearbox itself contains the differential and the equivalent of the driveshaft. In order to build a GT40 with a Mustang powertrain you’d need to increase the wheelbase by at least two feet, which would look kind of silly. So if your team of parts wants to play the sport of pushing a mid-engine car around, you need to start with a gearbox that directs the output in a “T” configuration rather than an “|” configuration. This is why there is a limited, and somewhat expensive, choice of transaxles for a GT40.

So to answer your question, yes, there are some fundamental issues of available space, geometry, and fitment that will dictate what parts you can and can’t fit into a GT40.

 

Again thanks Mark,
You put the things so simple...
sorry that I had you to go thru so obvius things.
So, to start putting all my ducks in a row...in your opinion what could be the less expensive combination of the main mechanical parts? (Without any custom/special work).

Regards
Javier

 

[Gordon Levy]

do you plan on building the car yourself or buying a turnkey? We offer different levels of kit as well as turnkey cars. Our base car have a 300hp 302 carberated and a readily availablr Audi gear box. We can inject the engine if that is what you wanted. This would be a very reliable daily driver. If you want, E-mail me with specific questions and I would be happy to answer them for you.

 

[Guest]

Javier, You have been given good information here on the state of what is available for a nice GT40. There is a kit out there that make s a little more use of Mustang parts, but is ugly! I am confident that no one on this forum will disagree with that statement. As mentioned, if at all possible, I would suggest a turnkey or turnkey-minus kit. This would let the constructor do most of the part matching for you. The components used in the various kits do seem like an odd mix I suppose, but they have all been carefully chosen. There are obvious compromises in all of the combinations, but all are sound as long as some care is taken in the horsepower used and/or driving techniques used. Given your feelings about the amount of horsepower you would feel comfortable with, kits that use the Audi transaxle would certainly be acceptable for you and are considerably cheaper than other options. A stock or mild Ford 5.0L/302 V8 would be a very excellent choice of engines, especially with this gearbox. With mountainous terrain and large changes in elevation encountered in Chile, I would argue for a late model Mass Air EFI (1987-1995) engine. To fit in a GT40, one must just use the upper intake from a 94-95 5.0L Mustang or Thunderbird.

The turnkey cars are just that: when they come, you turn the key and drive them. If you would like to save a little money and get some mechanical experience, the turnkey-minus cars generally come with everything except the engine and transaxle. Of course, the availability of Ford V8s and Audi transaxles in Chile would have some bearing on this choice. Kits that use Porsche or RBT(ZF) transaxles (considered by most to be stronger than Audi and requiring a less conservative approach to driving when modified engines are used) would also be fine choices. (The ZF is found in the DeThomaso Panteras and Mangustas.) These would make modifying your engine to provide more HP and torque in the future a less problematic decision in my opinion. But in any case the installation of the engine and transmission is not an extremely hard thing to do as long as one has the tools to handle the weight (or access to them any way.) The EFI engine is, in some respects, actually easier. There is less tuning and "fiddling" with it once installed. Transmission install is very straight forward.

If you are in Santiago, perhaps we can meet and talk about it. I will be in Santiago on either 8/3 or 8/5 through 8/7. My plans are not finalized, but I am hoping we will be there on the 8/3 because I would rather spend the weekend in Santiago than Buenes Aires.

Regards,

 

[Mike Dozier]

Javier

If you are on a tight budget, suggest you look at a Factory Five Racing Cobra.
It's designed to use a late model Mustang
as a donor, has great looks and performance,
and is easy to build.

If you have your heart set on a GT40,
you'll have to spend LOTS more money for
a decent one.

MikeDD

 

Lynn,

Happy to see you if you come to Santiago.
Let me know when you are sure about your dates. We can fix a good plan for the weekend...ski maybe?

Regards,

Javier

[ June 21, 2002: Message edited by: Javier Jose ]

 

Mark, Gordon, Lynn, MikeDD,

Thank you all for your help.

This is going to be harder than I thought... but rewarding.

Javier

 

[Ian K]

Javier,

Looks like you got your answers.
Sorry I didn't reply, but I was on vacation
and dealing with family tragedy.

Your best bet would be buying either a
turnkey minus or a complete kit. CAV and RF
have turnkey minus, RF and Tornado do
complete kits. With either choice, all you
really need to source is an engine and
transaxle. As others have said, for your
goal, a stock 302 and an Audi trans are
cost efficient and will suit your needs fine.

I forgot to mention that Tornado's complete
kit used to include an engine and gearbox.
Not sure if that's the case still.

Ian

[ June 25, 2002: Message edited by: Ian K ]

 

Ian,

Sorry to hear that.
It´s never to late to help. And of course I have many more questions to go round.

Regards,

Javier