Alternative GTA conversion.

I was going to build a 21T sprint/drag car this year but would like to invest the time and money in doing the same to a GTA. I have harboured an idea for a couple of years now and wondered what you thought about this idea. American V8 power! All the parts are available off the shelf to bolt the Renault transaxle to a variety of American engines for the kit car industry. I need to look into which engines are lightest to keep the weight distribution similar - but it would only require the fabrication of engine mounts - no complicated ecu's to worry about. A friend of mine had a properly rebuilt 400bhp V8 (I think it was the 5.7 Chevy small block, but I'm not 100% sure) crated and shipped and it still didn't cost him much over £2000 delivered. My mate is going to run his with 200 bhp of Nitrous as well! In a spaceframe Mini!!!!!!!

Tony, I have a rolling stripped shell, including all panels but no rear glass, has perspex to fit, includes gbox (and atmo engine that I would prefer to keep). Might be the ideal donor!

Your car may be ok for drag racing, but if you add nitrous they wont let you sprint or hillclimb.......you will also end up in the sports libre category with your car......so you will be up against much quicker machines at most events. Regs for sprints and hillclimbs have been seriously tightened up in the last 2 or 3 years.

None of the Yank V8s will be lighter than the Renault, all cast iron bottom ends, apart from the new LS1 Corvette engines (which can be picked up for around £3000), but then they are Efi. The Rover V8 is lighter than the Renault V6, and the adaptor plates are cheap, but the engine is so hard to get any power out of, best of finding a second hand Chimera/Griffith lump.

Main downside is the Renault box wont be able to handle over 400lb torque at such low down revs

Tony, I have a rolling stripped shell, including all panels but no rear glass, has perspex to fit, includes gbox (and atmo engine that I would prefer to keep). Might be the ideal donor!

Id love to have a GTA like this, strip all the body shell off and have it like a Lotus 7/Ariel Atom type affair! It would be light!

Whats stopping you? It would only weigh about 500kgs! You'd need to rig up lights and cycle type mud guards but thats about it! We need to see a picture of Ruperts car to get an idea of what it would look like.

[Alpineandy]

None of the Yank V8s will be lighter than the Renault, all cast iron bottom ends, apart from the new LS1 Corvette engines (which can be picked up for around £3000), but then they are Efi. The Rover V8 is lighter than the Renault V6, and the adaptor plates are cheap, but the engine is so hard to get any power out of, best of finding a second hand Chimera/Griffith lump.

Main downside is the Renault box wont be able to handle over 400lb torque at such low down revs

I assume the idea of a yank motor is power per pound (sterling),
and power to weight rather than just light weight.

Gearbox-wise there are upgrades such as :
http://www.bell-performance.co.uk/gearbox%20upgrade.htm
But I think it would be expensive......

[Alpineandy]

http://www.tornadosportscars.com/TS40/partslist.html
These guys will even do you a 6 speed box for only POA ..

http://www.tornadosportscars.com/TS40/partslist.html
These guys will even do you a 6 speed box for only POA ..

The Mclaren kit I sold a while back was a Tornado kit. Ive spoken to them about the 6 speed box, still has standard internals with a 6 cog tacked onto the end.

The Renault box is not good enough for really fast shifting youd need for strip use. Youd need something really good like a late Audi RS4 transaxle, or Porsche G50, but its expensive, and also the gearing is wrongly spaced on the Renault box to, 3rd is too short and 4th is too long. The Europa cup models had 1.19 3rd gear ratio to do 110mph at 6100rpm instead of the usual 86..

Whats stopping you? It would only weigh about 500kgs! You'd need to rig up lights and cycle type mud guards but thats about it! We need to see a picture of Ruperts car to get an idea of what it would look like.

..probably look like something out of Wacky Races! Speaking of hybrids, id like to have a GTA, remove the rear fibreglass bulkhead and rear seats, seperate the cabin with a bulkhead just behind the front seats, and turn the engine and gearbox round, so the the car's mid engined! Youd end up with one hell of a boot!

The mini I mentioned isn't mine and is for drag/road!!! use. The guy is a bit mad! I wouldn't be too bothered about classes with the GTA - just want to do it to have fun - if I was competitive it would be a bonus - not to mention a surprise!

You say that now, but coming last all the time isnt fun and gets frustrating! If I were you I'd avoid the yank lumps.....soooo heavy. If youve got money you could easily get well over 300bhp out of the standard engine. Big turbo £500, cams £350, chip £250, exhaust £200...err cant remember, actually could be more but never mind.... air filter.....£10 for a foam sock to put on the old pipe and bobs your uncle. Strip out the interior and replace glass with plastic and the weight you will save (on that and the increased yank V8 weight) will more than make up for the extra horses your V8 would deliver. While youve got the engine out you could always get the heads flowed and ported (£1000ish) and you'd add another 10 or more BHP.

I think Peter needs to give some test drives in his car to show what it goes like!

Honestly, if I was going to change the engine for something else just for drag or strip use, the Cosworth turbo is a good option, only because of the wealth of tuning parts and ease of tuning available. Adaptor plates are available for this engine to the UN1. 400bhp is very easily acheiveable.

The best option staying V6 is the Peugeot 605 24v lump. It has over 40% more valve and port area than the Renault V6 12v. It has 37mm inlet valves and 32mm exhaust valves, this is more than Cosworth, R34 Skyline, BMW M3/M5...it is a very high spec setup

I would flat top the pistons, as with the 610 to a 7.6:1 compression, and I can get hold of Venturi 400 Trophy spec cam profiles. With some manifolds and a decent turbo, 430bhp is easy (as with the 400GT, which only ran twin T2's =, very small). The next cam grind they specify does 500bhp at 1.3bar boost, on T25's . Again, most of the fine tuning is in the engine management, but thats easily sorted soon too....

I agree with David on the idea of the ford cosworth engine, an easy 400hp simple reliable conversion. As a rallycrosser it would be pretty competitive too. So who is going to do it then? I'm broke.

[Alpineandy]

You say that now, but coming last all the time isnt fun and gets frustrating! If I were you I'd avoid the yank lumps.....soooo heavy. If youve got money you could easily get well over 300bhp out of the standard engine. Big turbo £500, cams £350, chip £250, exhaust £200...err cant remember, actually could be more but never mind.... air filter.....£10 for a foam sock to put on the old pipe and bobs your uncle. Strip out the interior and replace glass with plastic and the weight you will save (on that and the increased yank V8 weight) will more than make up for the extra horses your V8 would deliver. While youve got the engine out you could always get the heads flowed and ported (£1000ish) and you'd add another 10 or more BHP.

Peter, Your saying this to the guy with 'probably' the most powerful GTA in the country. Because he likes drag racing and knows that parts and power for them are sooo cheap, I think he's sounding out alternatives.
The PRV isn't a particularly light motor, But I personally think he should keep it. But It's worth asking opinion on here.