Garrett GT3788R...the middle ground between a GT35R and GT4088R?

[arknotts]

I've been looking at the GT35R for a while now since I've wanted a fast spooling turbo with good midrange power. However, the GT4088R provides more power potential while sacrificing a little spool time.

Garrett also has the GT3788R which *supposedly* provides the spool of a 3582R with the flow of a 4088R. This quote has been passed around some other message boards. I'm not sure of its source, but it sounds like it's from Garrett:

The End of Compromises Many racers who compete at the top tier of Time Attack, Gymkhana and road racing have had to decide between the response of the GT3582R and the higher horsepower GT4088R. They came to us looking for a turbo that would provide the best of both worlds and we have delivered the answer; the Garrett GT3788R!
The Garrett GT3788R (PN 772719-1, 2, & 3) is outline interchangeable with the larger GT4088R but with similar responsiveness to the smaller GT3582R. The GT3788R is perfect for 2.0L - 5.0L engines looking to make 440 - 675 HP. The twin scroll design of the T4 turbine housing assists in spool up.

I've rarely heard this turbo mentioned around here, but it seems promising if what they are claiming is true. Does anyone have any experience with the turbo? Does it really provide the best of both worlds or does it just split the flow/spool difference between the 35R and the 40R?

http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT37/GT3788R_772719_1.htm

 

[jza75r]

I wish somebody could shed some light on this subject I was wondering about this turbo too. I'd be using it on a 1jz

 

[ohiosupramst]

A t67 is very close to the gt37 therefore many people just call it a t67. Dale on Ohiosupras.org is making close 700hp with a t67 at 32psi with e85. If your looking for up to 550whp I say a gt35 or sp63.

 

[sthmstr]

I have been looking at the gt3582r personally for my 7m and have rode along with a 4th gen running a gt40. The gt40 is pumping out about 750whp on e85 and a stock engine. He was cruising with another 4th gen that was running a precision billet in a slightly larger size on race fuel. Both supposedly making same power the garrett spooled way faster from any kind of pull.

According to the comparrison chart on Garrett's site looks like there's 3 different compressor and turbine options so tough to say what exactly it would behave like.

http://www.turbobygarrett.com/turbo...rgers/GarrettTurbochargersComparisonChart.pdf

 

[Neodeuccio]

I've been considering both the 35 and the 40 for my long-term build, but I've never heard of the 37. Sub'd for more info!

 

[kamikazemkiii]

Ive heard that the 37 spools quickly like a 35, but hits like the 40.

 

[rwd]

37 is not a good choice,i've tried 4088r/3788r/3582r back to back on 2jz , and i perfer gt4088r of the 3 , best power and come only 300rpm after gt3582r,gt3582r is good too but i cant use my 1-2 gear at full trottle,tire only spin... .gt3788r come at the same rpm than gt4088r and give less power

 

[sthmstr]

37 is not a good choice,i've tried 4088r/3788r/3582r back to back on 2jz , and i perfer gt4088r of the 3 , best power and come only 300rpm after gt3582r,gt3582r is good too but i cant use my 1-2 gear at full trottle,tire only spin... .gt3788r come at the same rpm than gt4088r and give less power

Great info! Good to now how they behave from experience. By what rpm does the turbo hit full boost? Also What size rear tire are you using?

 

[rwd]

not sure for full boost but i think 35r is around 3900rpm and 37r/40r around 4300rpm.

For my tire i'm using 255 at the rear

here to give idea:
2jz , gt3582r .82a/r , 21 psi , jdm stock cams , spa cast manifold , 3'' exhaust , wastegate discharge in downpipe:

2jz , gt3788r .89a/r , 25 psi , bc264 cams , boostlogic tubular manifold , 3'' exhaust , wastegate discharge in downpipe:

2jz , gt4088r , .95a/r , 23 psi , jdm stock cams , godspeed tubular manifold , 3''exhaust , wastegate discharge to atmosphere(is not the final dyno sheet , the final one pull until 7000rpm and have better fuel ratio but it is at 18 psi i think this one is more comparable):

 

[sthmstr]

Great info dude! Thanks! Helps me decide lots easier!