Savington

iTrader: (31)

Planning out my DIY turbo setup around a T25 setup. I'm shooting for anywhere from 200 to 220rwhp, obviously with a preference towards 220. I'm going with a T25 because, for now, I'll be happy with 220rwhp. (power/weight ratios shows my car will keep up with an STi at 170rwhp, so I think 220 will suit my fancy. )

I'm having a hard time finding dyno numbers and graphs for the T25 .48 A/R, though. If I'm not looking hard enough, please link me (or tell me where to look). If you have a setup like this, post it up and tell me how soon you're spooling the turbo and how much power you're making. If I can hit 220rwhp on 12psi, I'll be a happy camper. I'm planning on starting with a new BEGi manifold and DP, but the rest of the kit is up in the air right now.

cjernigan

iTrader: (13)

Sounds like you're looking at a setup exactly like SamNavy's and he has a writeup for pretty much every aspect of his install. He is also running the Begi mani/dp.

TheBandit

iTrader: (8)

You should be real with yourself and understand that 200whp isn't going to be enough. There is never enough, and with a T2 footprint, you are going to be leaving yourself only a few expensive options for turbo upgrade down the road. If you go with something that has a T3 footprint, you have many more options and a much larger region for upgrade when you decide to do so. Just throwing it out there for ya, if not good luck with the T25.
-Michael-

samnavy

iTrader: (7)

His number of 200-220rwhp will achieve his goal of putting distance on a stock STi from a roll. An upgrade from a T25 to a T28 is hardly what I would call expensive. The expensive part will be the new engine management to safely run more power down the road. A T3 has the advantage of achieving much higher HP numbers, at the expense of spool and DD. I've said it once and I'll say it again, a plain-Jane .48/.49 T25 is arguably the best choice for a 200rwhp setup. They are super cheap, start to spool about 2000rpms, capable of an efficient 240rwhp, everybody makes parts for them, oil/water... it's a no-brainer.

Savington, I've been saying it for about 3 weeks now, but the holidays and my injector issue got in the way. I'll be taking my car to the dyno late next week after my 305's get back from the cleaners. I expect (with the setup in my sig) that I should be able to achieve 200rwhp at 10psi. I've been having a boost overshoot problem that I expect to be able to solve with a helper spring. We'll see if 12psi is possible but I won't sacrifice A/F's to do it.
Here's a link to my build thread, it will walk you through every part on the car, why, theory, price, engineering, everything:
https://www.miataturbo.net/forums/showthread.php?t=4455

rmcelwee

iTrader: (1)

I love my Miata with 200 HP - heck, my other Miata with 123 HP is fun too! I don't see anything wrong with a 200 HP goal. 10 years ago, you never saw anyone with more than that and we all had smiles on our faces.