My housemate has a Rev2 MR2 turbo and after lurking around here at my reccomendation he has decided that he can no longer live with miatas making more power than him!

So he has asked me to give him a hand with building his engine and upgrading the turbo with a power goal of 320-350bhp in mind.

So far we have assembled a shopping list of bits and materials required for the upgrade. This includes: Rods, MS, COPS, new manifold, new down pipe, etc.

What I'm not sure of is which turbo to use. Being a 2 litre I initially thought of using the GT2871 (maybe even go baller v-band like Sav). But my thoughts keep drifting back to the 2860rs which I think would have killer response on this setup.

Can some one offer some opinions on this?

He also has his heart set on an external wastegate. I know that this is available for the 2871 but after searching for I bit I turned up nothing on the 2860. Is there an EWG solution for the trusty tater?

Thanks

Tom

 

housemate = life-partner

If you wait a little while you can compare pre-pubescent Savington's 2871 data to my gt2860rs d1zc0 p0+@+0 on the same motor, manifold, and exhaust. Look at the ATP site/catalog, you can get the housing with our without the wastegate and they're the same for both turboz.

 

the mr2 is a low compression 2.0L. 3076 sounds fun.

 

The 2860 is too small for that motor. The CT20B that came on the japanese 3rd gen 3S motor is about equivilent to a gt2871. My old MR2 which had a Gen 3 motor with the CT20 made 310whp at 21psi.
You would be much better off with a GT3076.

 

There are a few people making 300whp on a GT2860, but they are having to try real hard to make it there. Most people I see running in the range your roommate is looking for are running a GT3071 or a TD06.

 

Double post, I suck at the internet.

 

theres most likely a good amount of people making 300 on a 2860 with a 2L and im about to be one of them.

 

In my experience the 3S-GTE doesn't make power on the small turbos. The CT20B is pretty close to a GT28 and it took over 20psi to break into 300whp, and that was with cams, WI, and a higher compression bottom end with a Power FC.

 

Is the CT26 a direct drop in upgrade?

 

The Gen 2 came with a Twin Scroll CT26 from the factory. The 7M-GTE single scroll CT26 has a bigger hotside, but is a terrible match for the 3S.

Your best bet is to go to mr2oc.com or mr2boards.com, there is way more information available there.

 

The weak link on US motors is the intake manifold. It doesn't distribute the charge evenly, and #3 (I think it's that one, it's been awhile) runs lean. It cooks even if you pull timing to prevent knock. Everyone seems to have trouble at about the 340 whp range with the stock intake mani.

If I was going to do one, I'd make a good exhaust manifold, use a Disco Potato, and a new intake manifold.