Choosing A Turbo

[rinmak]

Hey guys,

Currently im building a 180sx with an RB25DET in it and just need a few tips/pointers as to the turbo setup i should run. I have searched and so far the most tempting turbo I can find is a HKS 3037S 52T .87. My goals for the car:

- 350-400rwhp

- Step 1 cams

- Headgasket (8.5 CR)

- Supporting fuel system

- PowerFC

- Stock bottom end

- Used for drift events/street

Can anyone suggest a better turbo for my project? If so, what and why is it better?

Also just need some educated guesses as to when the 3037 .87 will make full boost (lets say 17psi) and what sort of power I can expect from this boost on a good condition RB25.

Thanks heaps,

Ryan.

[Kaido_RR]

im running a HKS GT 2835 PRO S, full boost by 3300rpm (16psi) max power 337rwhp (very very rich tune 11:1 afr)

running stock engine (only got 740cc injectors and z32 afm + pfc) and my engine got 125,000km +

Both the gt 2835 pros and GT-RS make similar power and come on boost hard and fast;

I use to do abit of drifting and found the 2835 to be awsome comes on boost very fast and once it was going i never saw much lag at all and even at 337hp it was enough to get the r33 sideways

Good luck

[BHDave]

52 trim 3037 would be my choice as well but step down to the .63 exhaust.

I'd also leave the stock head gasket alone.

Check this thread out for a garrett alternative using a 52 trim wheel (garrett only offers 56 trim normally). Cost should be significantly lower than the HKS.

http://www.skylinesaustralia.com/forums/in...howtopic=147580

[rinmak]

' date='27 Dec 2006, 02:38 AM' post='2775209']

im running a HKS GT 2835 PRO S, full boost by 3300rpm (16psi) max power 337rwhp (very very rich tune 11:1 afr)

Thats some good power. Out of interest, when "Pro" is used in conjunction with HKS turbos does it generally just mean they are internally gated or are there some other important differences?

52 trim 3037 would be my choice as well but step down to the .63 exhaust.

I'd also leave the stock head gasket alone.

http://www.skylinesaustralia.com/forums/in...howtopic=147580

Im coming from a CA18DET so i just assume changing the head gasket is a necessity for running high boost ....is it not that necessary with RB25DETs? Also, the reason im after the .87 A/R is mainly so that there is room for expansion later in case I want to go higher (lets say i break my engine then get it built). I saw a thread somewhere on here where someone was making about 400rwhp but on the .63 version and he actually said he preferred the .87 as the .63 was to responsive (i like that nothing, nothing, BAM! feeling). As long as full boost is before 4k I would be happy.

Edited December 27, 2006 by rinmak

[rinmak]

Bump...anyone?

[Kaido_RR]

Thats some good power. Out of interest, when "Pro" is used in conjunction with HKS turbos does it generally just mean they are internally gated or are there some other important differences?

not sure

the turbo is great, with a retune (11:1afr at the moment) im hoping for around 350rwhp @ 16psi, looking to drop some tomie pon-cams and headgasket in the future and see what is makes around the 18-20psi mark hopfully high 300hp

[Slide]

Garrett GT30R

The winner between 270 and 300rwkw

Without spending over $1700 on just a turbo.

[rinmak]

Garrett makes no sense to me..

Is this a GT30R?

http://www.horsepowerinabox.com/HPIAB2/prod18.htm

Would you suggest the .82 exhaust housing? Its alot cheaper than a HKS item which makes it tempting. Are there any major differences between them or are you just paying for the badge with the HKS one?

Edited December 28, 2006 by rinmak

[thizzle]

hks gtrs = better for drift than a big ass garret.....good for 400rwhp with cams..boost at 2800

Edited December 28, 2006 by thizzle

[sinistaGTR]

gt3040 .63 ex housing

[Kaido_RR]

hks gtrs = better for drift than a big ass garret.....good for 400rwhp with cams..boost at 2800

didnt think the gt-rs could make it to 400rwhp as its rated less than the 2835 pro s

[thizzle]

my tuner made 404rwhp @ 1.38 bar with it...dyno in rb25 results thread........i wanted the pro s tuner said wait for gtrs..

Edited December 28, 2006 by thizzle

[Kaido_RR]

my tuner made 404rwhp @ 1.38 bar with it...dyno in rb25 results thread........i wanted the pro s tuner said wait for gtrs..

awsome results

[R31Nismoid]

I still doubt the GT-RS ability to rank out 300rwkw, seems only one person has done it, and no-one else has come close yet.

Most are short around 30-40rwkw

[thizzle]

HUh??? maybe cuz its new and not many people have wacked big cams in with em etc etc...or the tune is safe.....cuz with just the turbo i only made 250....theres a 1st time for evrything.

Edited December 28, 2006 by thizzle

[Jetdat]

my tuner made 404rwhp @ 1.38 bar with it...dyno in rb25 results thread........i wanted the pro s tuner said wait for gtrs..

that is very impressive from a GTRS..

265rwkw @ 15psi, modest tune due to standard internals, with 2835 pro s...

extremely happy with lag, drivability, power delivery..

[rinmak]

Any comments on this turbo guys? Is this the GT30R Slide mentioned earlier?

http://www.horsepowerinabox.com/HPIAB2/prod18.htm

Its a fair bit cheaper than the HKS 3037S so if it can do the same job that would be awesome. Would you guys recommend this turbo in .82 for a 350-400rwhp 25?

[R31Nismoid]

HUh??? maybe cuz its new and not many people have wacked big cams in with em etc etc...or the tune is safe.....cuz with just the turbo i only made 250....theres a 1st time for evrything.

Maybe, i'd like to see at least one other car make 300rwkw/20psi though.

[Slide]

Any comments on this turbo guys? Is this the GT30R Slide mentioned earlier?

http://www.horsepowerinabox.com/HPIAB2/prod18.htm

Its a fair bit cheaper than the HKS 3037S so if it can do the same job that would be awesome. Would you guys recommend this turbo in .82 for a 350-400rwhp 25?

The Rb25 turbo upgrade thread in forced induction shows a few results with this turbo.

Its quite common to see 265-275rwkw at 16-17 psi

Power just seems to hit you when you want it whilst drifting i have found.

The GT30R (GT3076) is not the same turbo as the 3037s listed in the link above.

It is rated to the same power how ever has a .70a/r compressor cover usually found on the GT3040 etc rather then the .60 on the GT30R.

[discopotato03]

Yes I agree , I've never yet seen a real GT3076R with a .70 A/R compressor housing . You could nearly bet that thing is either a GT3040R (GT3082R) or one of the victim grade GT30+ TO4S compressor wheeled horrors .

With the real GT3076R's (cartridge wise same as HKS's GT3037's) the power rating is claimed to be 450 and 480 PS for the 52 and 56 trim compressors in Garretts TO4E .60 A/R port shrouded compressor housing .

Cheers A .