Zero R

I would say GT42 with the larger compwheel 5" Dp is a good idea, if your already cutting what it is the difference, let me know what your doing to the motor, I may have very similar dyno charts.



-Sean

87GTR

I say twin GT40's

an_juan

I've made up mu mind and ordered a gt40r and 40 mm wastegate from atp turbo. I prefer midrange over top end power as most of my driving will be street or road circuit. I might drag once or twice a year.

boost_creep

Good choice.

Badog

If a GT40r is good for a 13BREW, then it should be a mid-range monster on the 20b! After all, the stock twins were the same on both engines, but some difference on results! Good choice. Love to see that exhaust manifold when you're done. Which one are you going to use? Build one?

an_juan

actually, the rear turbo of the 20b stock twins is larger than the front.



Anywho, I'll make my own header, equal length. I've sourced out 321 stainless steel tubing from burnsstainless.com

Zero R

I think the choice is descent, it would of been a little better to go with something a little bigger, the hotside on the 40R is a hair on the small side for what your going to be running, you wouldn't need to trim the shock tower either, I also could have set it up to run a smaller DP for you as well if you still wanted, and boost response would have not really been sacrificed. I know ATP doesn't have your turbo yet only because I don't have any of mine, so let me ask you again what is your motor setup like? I think you can go a little larger, get pretty darn close to the same response with much better power, let me know if you want any help.630.543.8890, I can also get my hands on some GT turbo's that ATP can't which might be better than the two your considering.



-Sean

an_juan

12 and 18 psi on pump gas for the street and track, respectively.

stock port 20b.

intercooler, intake, blah blah

ATP turbo recommended the gt40r over the gt42r for my application. They also said that I can't pick and choose compressor/turbine wheels like other turbos. So my choices with Garrett are pretty limited. I also like the price of the gt40r.

Badog

Investigate Rotor_Dee's turbo in the works.

http://www.reactiveracing.com/



I think between the GT40r (from Aspec of course) and other new things coming out, you have some choices.

Zero R

I could have matched ATPs price on the 40R, they are knowledgeable but not rotary guys, if the motor is a stock port, a GT40R won't be too bad, but leaves you little room to grow, as far as mixing and matching wheels you can. But you will need part #'s which you don't have access to and be very careful on the choices, because the wheels are very closely matched already, other than that choices are only limited by Garrett part numbers, and some parts compatablity, ie. can't put nonBB housings on BB center sections.



-Sean