I'm hoping some of you experts on here can give me a steer towards my next mod?

I've got a 97sti v3. Just been rebuilt with cossie pistons, arrow rods, ACL bearings, ARP head studs and cossie baffled sump plate. It's running a autobahn FMIC, 850 injectors, simtek and TD05 20g with uprated oil and fuel pump. Also got equal length headers and a full 3" system (sport cat). I haven't had it rolling roaded yet but I guess it's running in the high 300's. I'm still on the original TY752 so that is probably on borrowed time. So I assuming I get a 6 speed what would be the best turbo for me bearing in mind it's my daily driver but also for track days. MD321?? I think I would be happy with 400-450. Is there any point in changing the heads to a later model or get my existing ones flowed? Is the autobahn FMIC limiting this set up, I've read some negative stuff on here? Thanks very much in advance for any advice.

 

oil cooler

 

I'd replace the Autobahn FMIC for a Hybrid GTSpec2; MD321T (or SC46 Billet) turbo.

Your stock STi v.3 heads are good for up to (possibly over?) 500+, so no need to change.

740cc injectors (possibly even 650s?) would prob be better for low-speed running (and maybe fuel cons. too?). But your 850's prob are gonna be fine... I don't suppose you've had any problems with them to date?

 

And yes, your 5-sp peobably won't be long for this world.

 

Thanks fellas

Oil cooler, yeah good call.

I have only just had the 850's fitted and the only reason I went for them was I got a really good price. To be honest the fuel consumption is no worse than my 440's and GEMS and the idle is better (although I do get the annoying simtek hunting idle when it's warm!)

 

BTW, do you know exactly your current bhp/lb ft? How long have you been running the 20g on your 5-sp? (I'm interested, as I'm going the 550s/20g/FMIC route, myself, lol).

 

I've only had the car for a year with the 20g and the previous owner at least another year before me. I've got a rolling round printout at 380 bhp with the gems/20g but I can't recall the torque. When I dig out the paperwork I'll get back to you. Gearbox is holding well so far!

 

So the previous owner had the 20g on for at least a year too - so a min. of 2 yrs total?

Or did you fit the 20g when you first got the car - so only 1 year with it on?

 

No the 20g was on for at least 2 years!

 

Gives me some kinda hope re the g/box, that. (I don't do launches/superfast changes, etc.).

 

I ran a 20g on a 752 box for about 18 months it ended up at 399bhp360ft/lb and the box was fine now changed for a 6spd and an md 321t which i would highly recommend it is more resposive than the 20g and makes alot more power.Ref the 20g I wouls run with a sti8 topmount rather than the fmic as I though it drove better.

 

Before you invest in an oil cooler would it not be worth finding out what your oil temperatures are? There are a lot of Classics with oil coolers that do not need them
Oil Temp guage is £40-£80 depending on what you choose. It may save you the cost and hassle of an oil cooler.

 

Very true, thanks Harvey!