Ok, I'm looking to turbo my car, but am on a budget right now. Iwas thinking abou getting a used turbo off of ebay. There are a lot of T3 turbos, for good prices. I plan on rebuilding anyways, but here are my 2 questions.
1) Would a T3 turbo work very good on the 420a (temporarly)? How much boost would I be able to run with a FMIC? What about a SMIC?
2) Could I get the compressor from the T4 and make my T3 into the T3/T4? I really have no idea, and this might be a really dumb question, but I would like to know. Thanks.

a decent t3 will do everything u will need for a good while till u max it out at like 15-20psi depending on turbo and setup

yes u can buy a t4 compressor housing and a t4 wheel and change your t3 to a hybrid

I use a strait T3 turbo on my setup. It will do 20psi ez. If you go to turbofast and use there turbo calculator it will tell you what size turbo to use.
http://www.turbofast.com.au/TFmatch.html

I did it at 20psi and it said to use a T3 with a 60 tirm compressor to make ~324hp. My turbo spools quick, at about 2900rpm, and hold strong boost. The most I have ever done with it was 16psi, but that is because I don't have an ignition for retard. You can turn a T3 into a T3/T4, but there is more involved than you think. For the price of the housing, bearings, and compressor wheel you might as well just buy a T3/T4. You can go to Turbonetics web site and check out all the parts you would need to do this. Personaly I think the T3 is a great turbo.

Ok I did a little more research. Here are the results I got from the turbo calculator at 20psi with a front mount.

MAKE Garrett
TYPE T3
COMPRESSOR TRIM 60
TURBINE HSG A/R 1.06

That is not a T3. This is a T3/T4. The larges T3 you can get comes with a .82 AR turbine housing (acording to Turbonetics)

Here are the specs on a .82 AR T3 at 16psi and a front mount.

MAKE Garrett
TYPE T3
COMPRESSOR TRIM 60
TURBINE HSG A/R 0.8200000000000001

That is a strait T3 turbo. I is suposed to make ~258hp. This sounds about right because that is the kind of power I am making. So the T3 may just max out around 16-18psi. If you want run higher boost then go with a T3/T4.

What about a T4 turbo? I know it's bigger, but would it work?

You won't be able to spool a T4. The turbine on a T4 is huge.

You could spool a T4 with nitrous oxide.. ofcoarse it'd be a drag-only setup!

The Garrett T3 turbo is PERFECT for the 420A. It fits the engine bay like a glove and makes great power for our cars (like a 16G). For AT owners I recommend a .48/.42 small setup or .48/.60 large setup... if you're a 5spd owner, .48/.60 small or .63/.60 large. I recommend these turbos based on our engine size and the ability of the 5spd to rev higher.

You won't find a better turbo than the T3 to build a custom setup!

20 psi? I won't reach that for a long time. I'll be sticking to probably 8. I want to keep stock internals, and I will just run my engine into the ground. Then I'll swap withtthe 2.4L and build that up. Hopefully that wont happen for a year or 2 though.

Two years. If you are very lucky. It is going to blow at 6psi or 8psi. It is just a matter of when. You never know. Could be this week could be next year. Start building your spare engine now. My #3 piston cracked at 6psi on the second day of boosting.

Turning a straight T3 turbo into a T3/T4 is a little more complicated than buying some parts and bolting stuff together. id leave that to a "specialist". there is no "need" for a straight T4 turbo, unless you are building a drag car in my opinion, but you CAN use one on the street very easily, and spool up really isnt all that bad, considering it is a ball bearing. the owner of the shop i help at has a 93 Civic Hatch with a built LS engine, and T4 turbo. it spools suprisingly quick and has LOADS of top end. ran a 8.0 1/8th mile at 95 mph on slicks!

www.TeamKLR.com
1997 Silver RS
12.3@118mph,20psi, race gas(drag radials)
Wiseco 10.5 Pistons
Eagle Rods
T3/T4 Turbo
Custom FMIC
Greddy Exhaust
440's