I just cant make up my mind guys so I need some help from the experienced ones who actually have these turbos. My car will be mostly street driven and at the track about once a month. I want it to be a reliable 400hp street car, but able to turn up the boost at the track to like 500 or more if I want (tuned of course)

setup:

83mm Benson Sleeved GSR Block
9:1 comp CP pistons
Crower Rods
GSR head ef-1 Valvetrain
GSR tranny, Quaife Diff, Action 2md clutch
blah, blah, blah.

Anyway I read in this post https://honda-tech.com/zerothread?id=1099405
Where gt30typer made 512hp at 22 psi on an .82 housing with a gt40 compressor wheel with a gt30, but isnt that pushing that turbo to the limit??


I have a similar setup to what Espanol had in his car. His numbers are right on par with what I want. So let me get this straight his GT35R was made by Precision, not a direct from Garret correct?? Also that is a 5-bolt exhaust housing since it is from Precision,and also a GT40 56 trim compressor wheel correct?? Also on the turbine it runs .82 A/R not the 1.06 right??? Arturbo or DIRep972 your help would be much appreciated.

 

Hmmmm . . . maybe you can make 522-whp with a GT3040 with a big exhaust housing, but it wouldn't be very fun on the street because of the time it would take to spool (unless you're spraying it). On this turbo, we tend to think that the turbine wheel is too small to spin the compressor wheel up to its maximum potential. You can get 522 at the wheel, but the GT40 wheel compressor wheel is capable of a lot more.

We tend to believe that the GT35R with a .63 backside would be a much, much better choice for what you want to do, especially since you're only going to the track once a month. You could make more top end power with a larger A/R, but you also open yourself to getting beat by a smaller turbo racing stoplight to stoplight.

Again, we want to remind people that the GT40 compressor wheel (82mm 50 or 54 trim) is NOT the same as the GT35R wheel (82mm 56 trim).

Rod Short
Sales Manager
Precision Turbo

 

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We tend to believe that the GT35R with a .63 backside would be a much, much better choice for what you want to do, </TD></TR></TABLE>

Totally agree. You really can't go wrong w/ the 35r.

Espanol had a GT35r w/ Precision .63 5bolt turbine housing. I know he was VERY happy w/ this turbo. It had great power and great response.

I thought about going w/ the 3040r on my own set up but I couldn't find any evidence that it was better then the 3540r. Spool looks pretty similar on it and power is down, so it just seemed the 3540r is a better combination.

 

Hey thanks for both of you guys input, it really helps towards my decision.

 

my buddy has the gt30r on an 83 mm typer built bottom end made 385 on pump gas on 15lbs of boost (the turbo isnt in its efficiency range until 22) with a very conservative tune thing hits full boost at 3800rpms spools quick i highly recomend it if your car is a street car and only going to the track once in a while thats how we are with our cars. I am currently building a new block 84mm bore and have the gt30r also turbo is awesome cant say enough about it, its a very underestimated turbo.

 

Is it possible to have the GT35 turbine with 50 or 54 trim GT40 comp wheel ?

 

I don't know if that's really possible without doing a lot of digging. Personally, I would just got with a GT4067 as an upgrade. This uses the GT40 turbine wheel with a 67mm compressor wheel. Will support up to 750-hp with proper tuning.

Rod Short
Sales Manager
Precision Turbo