Max boost on t28?

[lutsch'14]

I have a 95 s14 with a blacktop running a t28, walbro fuel pump,z32 fuel filter, megan exhaust mani., and full three inch exhaust. Just purchased a pbm high mount intercooler setup and I have a manual boost controller already installed. I haven't dyno'd the car yet and don't have an a/f gauge in the car . I was wondering what is safe boost to run on the stock injectors? and what kind of numbers I might see ,hp? By the way I did run the car at the track this past fall at 12psi on the sidemount and managed a 13.8 at 102mph so I have an idea what its at now just don't know how much further I can push it without upgrading injectors, maf,and turbo/tune. I autox the car mainly with hopes of doing some real track time in the future. I want as little lag as possible with around 300 to 350whp any turbo suggestions also would be appreciated. Thanks.

[D.Adams]

from another forum

S13 Red-Top T25:
Compressor: T-25, 60 trim 56mm 0.60 A/R BCI-1 compressor.
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.
Stock Boost: 7 psi
Safe Boost: > 13-15 psi After that The Turbo is past it's efficiency
Max Boost: 17 psi
HP Ratings: 240 - 250 RWHP
Type of Bearings: Journal Bearing


S13 Black-Top T25:
Compressor: T-25, 60 trim 56mm 0.60 A/R BCI-1 compressor.
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.
Stock Boost: 7 psi
Safe Boost: > 13-15 psi After that The Turbo is past it's efficiency
Max Boost: 17 psi
HP Ratings: 240 - 250 RWHP
Type of Bearings: Journal Bearing


S14 Zenki (1993-96) Black-Top T28:
Compressor: T-28, 60 trim 60 mm 0.60 A/R BCI-1 compressor in T-04B housing
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.
Stock Boost: 7 psi
Safe Boost: > 13-15 psi After that The Turbo is past it's efficiency
Max Boost: 17 psi
HP Ratings: 250 - 260 RWHP
Type of Bearings: Journal Bering


S14 Kouki (1996-98) Black-Top T28:
Compressor: T-28, 60 trim 60 mm 0.60 A/R BCI-1 compressor in T-04B housing
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.
Stock Boost: 7 psi
Safe Boost: > 13-15 psi After that The Turbo is past it's efficiency
Max Boost: 17 psi
HP Ratings: 255 - 265 RWHP
Type of Bearings: Ball Bearing


S15 Black-Top T28:
Compressor: T-28, 60 trim 60 mm 0.60 A/R BCI-1 compressor in T-04B housing
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing, Inconel Turbine Wheel.
Stock Boost: 7 psi
Safe Boost: > 15 - 18 psi After that The Turbo is past it's efficiency
Max Boost: 20 psi
HP Ratings: Approx. 300 RWHP MAX
Type of Bearings: Ball Bearing


N14 GTi-R (1990-94) T28:
Compressor: T3 Super-60, 60 trim 60mm 0.60 A/R BCI-1 compressor.
Turbine: T-25, 79 trim 53.8mm 0.86 A/R turbine housing, Inconel Turbine Wheel.
Stock Boost: 7 psi
Safe Boost: > 13-15 psi After that The Turbo is past it's efficiency
Max Boost: 17 psi
HP Ratings: 290 - 300 RWHP
Type of Bearings: Journal Bearing
Upgrades: Replace compressor Housing w/ S14 T28 and Max RWHP can be bumped upto 320

[KoukiMonsta]

why dont you get injectors? you got a bunch of other shit....and a z32 maf.

then get a tune for 15 psi and make ~250 whp. lag will NOT be an issue.

[Carbomb]

DO NOT RUN MORE THAN 12 psi on 370cc inj.

get 555inj and a z32 maf and run 21 psi. I DO!
well on highway, for drifting 13 psi is PLENTY for what im doing.

you will find a dyno of someone doing t28 at 12 and 14 psi 12 is iffy but ok? 14 is yikes.

gl adn get some inj and a z32 maf.
pm me for a FREE tune, I have a bin file for z32 555 and sr20det s13 i run FULL BOOST which is 21psi and it goes.

[Carbomb]

SR20 binaries


you can get a tune from this site, I would run a wideband (and knock sensor if possible) but the tune I have is on my other harddrive which has a virus so til I can get it fixed no other tunes avail. sorry

[koukiMonster666]

So I have a s14 with a (65F) motor I believe that makes it an s15 motor correct me if I'm wrong but I put nismo 740cc injectors and z32 maf with a large front mount stock t28 got a NIStune board and tune an I'm only making 240rwhp and 270tq at 14lbs are those low numbers or does that sound about right?

[Future240]

This post is old but has good info so I won't lock it. I wonder if those numbers are correct on the boost levels.

[gaz_moose]

Originally Posted by koukiMonster666

So I have a s14 with a (65F) motor I believe that makes it an s15 motor correct me if I'm wrong but I put nismo 740cc injectors and z32 maf with a large front mount stock t28 got a NIStune board and tune an I'm only making 240rwhp and 270tq at 14lbs are those low numbers or does that sound about right?

there is not much difference between an s14 and an s15 SR, the s15 can be identified by having the 'fins' on the front of the cylinder head between the VVt bulge and the cut out for the 'half moon' gasket.


I don't get why you would have bigger injectors/maf and still have the regular t28, a 2871r which is a bolt on upgrade would have saw you at 350hp. your 250 odd hp sounds about right as your turbo is your limiting factor.

[Kingtal0n]

original t-28 turbos are old and I wouldnt push one hard. 15psi is probably fine. anymore than that would significantly reduce its lifespan on a typical high mileage setup.

[TheRealSy90]

Also, anything over 12psi on a t25 is really just pushing hot air and not making any gains.