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handinpants
05-15-2008, 05:21 PM
how is it a s14 sr uses the same T28 turbo but 370cc injectors, whereas the s15 uses I think it was either 444cc or 475cc injectors. Are the 370cc injectors which I have on my s13 sr going to be adequate at stock psi levels with the s15 turbo?

KwKouki
05-15-2008, 05:26 PM
the bigger turbo is gonna make the car run rich, at stock boost you will be fine.

Blown240sx
05-15-2008, 06:23 PM
Why would the bigger turbo make it run rich? If anything it might run leaner if you push the s15 turbo to max psi with I think on those GT28rs is 16 psi. Watch the A/F with a wideband and see how it does. You might come close to maxing those 370s out.

singlecamslam
05-15-2008, 07:33 PM
i run a s15 turbo on stock 370 only pushing 6 PSI. You'll be fine as long as you dont go over like 10 or 12psi.

slider2828
05-15-2008, 08:50 PM
I think he just misspoke guy two posts up. If you swap the 440's I think those are S15 injectors, you will run rich as the stock computer won't compensate to the new injectors.

If you run S15 turbo with stock injectors 370's, you will be fine... Most injectors from the factory only run about 60-70% of capacity at stock boost. if you push 10psi, its about 70-80% and at 12psi about 80-90%. But anything over 12psi is about 100%. Not a good idea... OBVIOUSLY this all depends on tuner.... these numbers are just rough idea..... as an example...

Blown240sx
05-15-2008, 10:54 PM
Most of the time 85 injector duty is pushing it but I know some tuners who go for max power and will set there injectors up in the computer to run at higher than 100% by setting their injector numbers higher. Its up to the tuner though.

Im a big fan of safe when it comes to fuel systems.

Black240sxSD
05-16-2008, 12:35 AM
I think he just misspoke guy two posts up. If you swap the 440's I think those are S15 injectors, you will run rich as the stock computer won't compensate to the new injectors.

If you run S15 turbo with stock injectors 370's, you will be fine... Most injectors from the factory only run about 60-70% of capacity at stock boost. if you push 10psi, its about 70-80% and at 12psi about 80-90%. But anything over 12psi is about 100%. Not a good idea... OBVIOUSLY this all depends on tuner.... these numbers are just rough idea..... as an example...

i agree but i would not push the injectors past a 85% duty cycle becuase it is hard on them

fliprayzin240sx
05-16-2008, 03:23 AM
how is it a s14 sr uses the same T28 turbo but 370cc injectors, whereas the s15 uses I think it was either 444cc or 475cc injectors. Are the 370cc injectors which I have on my s13 sr going to be adequate at stock psi levels with the s15 turbo?

Yes its adequate but you still need something to add a lil extra fuel with the more volume air the S15 turbo is gonna push into your engine. 7 psi on a T25 is not the same amount of air going into your engine compared to 7 psi on an S15 T28.

IIRC, as far as the difference between a S14/S15 Spec S T28 vs the S15 Spec R T28 is that the Spec R are dual ball bearings with a divider in the exhaust housing. Also, S14 T28s are iffy, some are ball bearing, some are journal bearings. Can't remember exactly how you can tell what the turbo is exactly, think the best way to do so is by looking up the part number...