Can ne 1 recomend a turbo for a '89 gt4 celica

[Al]

They are new so theres more than one. However theres a 3 week wait from Japan. You will have to discuss with him the price. Its very reasonable for a brand new toyota turbo though.

[Twolitre]

I agree with Al, buy a brand new steel one if you can afford it, if you can't afford it, save up for it. The problem with ST185's is that they have a shit top mounted ic so you'll have to go front mount or water-air to get decent results and a decent downpipe to replace the factory pos
If your turbo is not in need of replacing there are other worthwile mods that should come first before turbo in my opinion.

[explosiv]

this is goin to make me sound real stupid but...
wot is a downpipe and wot does it do...also how does a water to air system work and is it more/less efficient than a front mount intercooler
cheers...>>eXpLoSiV<<

[Dell'Orto]

A downpipe is the the part of the exhaust system that comes directly off the turbo, usually replaces a catalytic converter or other restrictive iece of exhaust, and allows the turbo to breahte much easier, which in turn lets it spool up faster.

A W2A intercooler has the advantage of being able to drop intake temps to below ambient air temp, and generally have really short pipes from the turbo to the throttle body, which reduces lag. Main downfall is its extra weight to the car, and added complexity with the associated plumbing, heat exchanger and pump.

if you really want to get some decent power from your GT Four, I suggest do the basic intake and exhaust mods (inc. downpipe), follwed by an aftermarket ECU, then get some bigger injectors and a decent turbo.

[Al]

Downpipe is the pipe directly off the exhaust side of the turbo that lead to the exhaust. The factory pipe has nasty 90 degree bend in it which are not good for flow. Aussie Exhaust can sell you a downpipe for around the $500-$550 shipped depending on how the exhange rate is from Oz at the time of purchase.

As for water to air intercooling use the search.php

[Twolitre]

This is a downpipe and connects the outlet flange on the turbo to the front pipe on the exhaust, which comes out under the sump on a 3sgte, it will free up a lot of hp especially if you still have the cat in the stock downpipe.
Basically water-air intercoolers use water to cool the core instead of air so do not require airflow themselves meaning the IC can be placed in a position between the turbo and throttle body that greatly reduces the need for piping, thus reducing lag. A seperate radiator however is generaly mounted behind the front bumper to cool the water which flows over that core via piping to and from an electric water pump.
Efficiency seems to be a never ending debate but on a road car the benefits can be great.
The first legacy Rs and all generations of the GT-Four came equipped with them but you would want to find a complete setup from an ST185 RC which may be hard but are most certainly out there if you look hard enough.

[explosiv]

another stupid question...wots tha throttle body?

[Dell'Orto]

Its kinda like the throats on a carb, where the butterfly in the middle opens to allow more air into the manifold to be mixed with fuel.

[explosiv]

so the throttle body is the part next to the plenum chamber that the throttle and throttle cable is attached to right?

[Dell'Orto]

Sure is.

[Twolitre]

If you want a good website for learning all about the fundamentals of the internal combustion engine, than click the link below.
http://auto.howstuffworks.com/engine.htm

[Malcolm]

depending on what your final goals are, you could get your current turbo rebuilt + upgraded for between $800-1200 depending on whether it's steel or ceramic (almost certainly ceramic but may have been changed already), with that (or a ct20b), a decent intercooler, exhaust and the other basics you should be able to achieve mid-high 13s 1/4 miles in street trim, running around 13-17psi and without having to open your engine. If you want much more than that then don't bother with upgrading your turbo or getting a ct20b, go straight for a bigger aftermarket turbo and ecu, then your limits will be what the internals of the engine can handle, which if the ecu is well tuned should be reasonably high (although you will want a metal head gasket)