How do you get 450bhp in a GTA Turbo?

Can anyone tell me who I can take my Alpine too who would give me 450bhp for less then 50zillian pounds, if 450 is to much I understand, but I want as close to 400 as possible, any ideas......?

David G. will know.....but I suspect the answer will be very very expensive! Aim for 280bhp and its gonna cost you a thousand or so (turbo, chip, exhaust, air filter, fuel regulator). Above that you will need cams,(engine out fitment) programmable ECU, injectors and you still probably wouldnt get near 450bhp. The engine design is quite old, only has 2 valves per cylinder and 1 turbo.....you cant expect miracles. I suppose you could try nitrous, but you'd probably just end up with huge repair bills!

Hello! Depends why you want 400? Alpines on the road are as quick as most 300bhp 'other cars' just through torque and gearing. Theoretically, the engine isnt like most other cars where it would need strengthning internally. The crank and journals are very strong, the conrods are forged as standard and the pistons have 3.6mm domed crowned ADDED to the top of the pistons so they are immensly tough. To get anywhere near 400bhp, you will need a T3/4 Hybrid with the 0.63 turbine housing and 55trim compressor wheel, free flowing intake system, cams, 450cc injectors, 8.5mm leads, good downpipe and straight through exhaust, large flow redesigned manifolds, big intercooler or charge cooler, uprated oil cooler system and high capacity front rad, fully mappable ecu and probably in the region of about 25psi of boost. Throw in a 610 or Lotus S4 clutch, and to stop spitting cogs if your really rich, a UN1 strenghthed secondard shaft upgrade and rebuild for £2000! which will handle up to 500bhp/lbft,. All of that is after youve replaced your water pump, oil pump, etc... Probably about £4000-£5000 (excluding gearbox upgraded) plus fitting and rolling road time....but then you cant do that if the car isnt going to stop or go round bends at that speed!

Thanks for the info David G, I've had my GTA about 6 or 7 years it's done about 150,000 and was thinking its about time I sorted the engine it's sounded like a sewing machine ever since I got it but Its standard, I get blown away every morning by a Black M3 I can't seam to get near it, do you think 300bhp would would do the trick I've clicked on your website and it all looks good but how much would 300+ cost?

[stephendell]

Alternatively just drop in the twin turbo 24V PRV from a Venturi 400GT

Im not so greedy and only want 300bhp + or -.

I already have a pipercross air filter and a single exit stainless steel exhaust as well as a bleed valve.

What would be the next course of action ???? Chip first then turbo ???

If so, which turbo as you seem to have quite a few on offer.

Would I need anything else or is that it ????

In response to Wayne...get your car to a proper rolling road first, and check its running as it should in the first place. So many people should do this before any tuning. An M3 should not be a problem for a GTA. I friend of mine had an M3 and I had more midrange pull on him in my atmo, let alone a turbo.

As for Technics, the problem is the next step to feel any real considerable gains cost money. The most ideally suited turbo is the T4...at 1 to 1.3 bar of boost the turbo is at maximum efficiency so it means the coolest air...the other turbos will do the same boost but with more heat. You need the chip to run the higher boost and big turbo, so you really need to do the pair together!

Thanks Dave, I'll get saving.

The only other thing, is what do I do with my old turbo ?? Do you not doa part exchange or anything ???

Technics.....if you can hang on 6 months (buy the turbo 1st) I will be offloading my chip as (fingers crossed) there is a programmable ECU for the GTA coming on the market.....and I will be buying it! Bought a turbo from David...no exchange, you just have to sell it or junk it!

Is it possible to adjust the turbo actuator to provide more boost from a unmodified GTA ?

Yes you can, but its a pain as you have to take off all the heat sheilding to get to it, and the threads on the rod are usually seized, and the problem with the standard actuator is its welded, not bolted to the bracket, so you really have to take off the turbo to adjust it properly. Problem with the GTA is they have compressor surge, so they peak to a higher level for a second then drop back. The factory boost cut out is 14psi but to set up your car so it doesnt trigger it will mean peaking to 13.5 and holding at say 12psi. The chip changes the fuel map and raises this limit.

[Alpineandy]

I get blown away every morning by a Black M3 I can't seam to get near it

If you just want to win the traffic light GPs, Tony Smith will advise on drag racing mods.

If you want to be quick off the lights..get an atmo!

What about NOS The kits are only £300

That M3's got far too much, for the lights it slaughters me if i come up behind him at speed he accelerates as if im standing still, don't know if it standard but they do come with 320bhp, I want to suprise him.

I had NOS on a V6 cortina many years ago, Nos is great but a bottle only lasted 2 to 3 days.

I've a list of thing's that need sorting, it goes like this.

Brakes
Wheels
Suspension
Door hinge
Interior fan
Head lamp cover( cracked )
Clonking gear change
Power upgrade
Respray

I've already spent thousands on it ARR but still needs so much more, I see that David G could sell me most of the parts but who can do the work?