Turbo too small?
 

I am planning on boosting my 1.6 miata. MSPNP for tuning. This is a stricly autox/track day car. It is not a daily driver. I am looking for around 200-250 whp. I want a turbo that doesn't run out of steam in the higher rev ranges. There is a garrett 50 trim turbo selling locally for 100. Here is the specs:

freshly rebuilt, there's no shaft play and it spins freely. 50 trim T3 turbo, externally wastegated, .38 a/r, .53 intake and .47 exhaust

Would this work for what I want? Its externally wastegated and I know most people are internally wastegated. Can I revert it back to internal wastegates?

Thanks

Excuse my lack of knowlege on turbo's. I thought T3's were bigger than the 2560.

Someone please give the breakdown.

How come everybody thinks they need a T3 to make power? I've seen good power on a GT2560 such as 244 rwhp at 11psi with a hydra, and Paul is running 14psi? at puts over 300hp to the wheels with a MS! Correct me if I'm wrong but the GT2560 is a .64 turbine, .60 compressor. I haven't experienced this, but I believe that the GT2560 would probably be the best all around turbo you can buy for a street driven Miata. It should spool a lot faster than a T3 and as I listed above, you should make good power. I thought my SR20 T25 on 7psi made my Miata feel like a different car, and it probably didn't even have 200 whp...so I can't imagine a GT2560 with 14psi at 300 whp. That's F'n insane!

so this turbo should be a little bit bigger than the 15g im assuming? Then why would it be a t3?? anyways here's a pic

http://img119.imageshack.us/img119/4739/turbolv7.jpg

post pictures of the compressor and turbine housings

Internally gated turbos have the wastegate built into the turbine housing, so no. Most people are internally gated because it's affordable and "good enough", so there's no reason to revert back to it other than there not being a whole lot of EWG manifolds out there.

You will like the turbo car so much better than the stock it is worth it. And their should be like no spool time then.

But it still sounds weird t25, and t3 being smaller. or are the t25 and t3 different than the garrett turbo's?? That may be where I am falling shy?

I think i'll pass on this one and wait for another turbo

There is such a wide range of T3's that the smallest ones are smaller than the GT2554.

Not when the .48 turbine has a huge exducer. There's a T3 turbine option for the 2871R that drops the A/R way down and sticks this big honking turbine wheel on it. Spools the same.

t3 is just the foot print. Thats it..

I like that turbo size for your goals. It will have good response and ftlbs for the autocross..

I also agree with this too. If the wheel is too big, it still spools slower.

If you have the same compressor and a hotside with a smaller turbine wheel with a .63 and then a turbine with a bigger turbine wheel with a .63 turbine housing -the bigger wheel with spool slower..

That pic above looks like a pretty small turbo. It will likely do the whp you want, but it will take more boost. The TQ and spool will be sick though..

You think, but do you know?

a .60 Trim T3 is just slightly larger than a 2560, it's very much in line with a 2860. It's only bigger on the turbine. The compressor wheel itself is nearly identical (IIRC the BB turbos have a more efficient design) but the exducer and inducer size of the wheel are identical....the 2560 is a .60 trim 60mm wheel.

No. the compressor A/R has no effect on the size/performance of the turbo. A .60/.48 and a .42/.48 T3 (with all other things being equal) will perform exactly the same. A/R :ne: wheel trim

They are cheap as hell, have a more efficient turbine and are easily rebuildable & upgradeable.

a T3 .48 is equivalent to a T25 .64

How the fuck can you tell what the wheel trim looks like without even seeing the wheel? The only thing the trim refers to is the exducer^2 / inducer ^2

All T3s have a 60mm compressor wheel. the trim dictates the size of the inducers and ultimately to power output level of the turbo.

a .50 trim T3 is good for around 30 lb/min or around 290BHP - that's a good 230rwhp.

don't on account of all these people's assumptions and outright BS.

i would run it man, your should be happy with it