S15 T28 Boost

[Highboost180SX]

I have searched and only recieved vague results. What is the max boost i can run on the S15 T28? I want to feel everything i can get out of this turbo before i upgrade and I have not been able to find a definite answer. Would 20-22 PSI be out of the question? Thanks in advance

[punxva]

yes that is out of the question, if my memory serves me correctly u should only boost those to around 16psi before it starts losing efficiency maybe even less.

[KwKouki]

18psi is usually what they tell you is max. anything over would be out of range.

[WILDACEX187]

i've also heard of the 18 psi range

[Highboost180SX]

Well I guess time to upgrade 18PSI isnt goin to cut it. Thanks for the info guys, much appreciated

[harlockssx]

The biggest problem isn't just running out of efficiency, but the turbine blades themselves will start to wear prematurely at boost levels over 1.2 bar...it's the blessing/curse of the inconel wheel. They won't last for long at elevated levels. If you want to keep it T2, 2871R .64 AR FTW...spools like an S15 but breathes SO much better! ~370 rwhp is all most can get out of it though (with few exceptions). Good luck!

[Silverbullet]

2871R .64 spools slower than the 28R. Just look at the power rating.. significant difference. A 28RS may have similar spooling time with the 28R with slightly more power.

[kuramaya]

1.1 is a safe range for your turbo. Turn it up, as long as your motor is getting enough fuel.

[Flybert]

I run 1.2 BAR. Anything more than that is pointless.

[smelly240]

yeah - look at the maps for that turbo - really its happy at 16psi, 18 its at its huff... you better have somethin like 550s' 370s arent gonna cut it.

[Highboost180SX]

yeah - look at the maps for that turbo - really its happy at 16psi, 18 its at its huff... you better have somethin like 550s' 370s arent gonna cut it.


I have 550's and I see AFRs of 11:7-9 I need more power though, I guess instead of turning up the boost I'll upgrade

[sunnys14]

what about 1.2 bar with 480cc's?

[flamebag16]

wat bout s14 sr20det stock everything koyo rad elec fans fmic how much is safe to boost for daily driving and what should i get to get most power out of turbo etc etc thanks for the help in advance

[WILDACEX187]

s14 sr's still have 370's so no u'll need bigger injectors for a s15 turbo

[KwKouki]

My setup includes a specR t28 with 480s. If I catch a mindsnap I will boost 14psi max. Looking to stay around 10-12ish range for a bit. I dont need any more

[smelly240]

specR t28 eh? LOL -- all the s15 turbos are the same ;) but ur smart not boosting much more -

flamebag - u want to get bigger inj before turning the boost up past 10 on your s14 motor... your turbo is a t28 as well, and the 370s arent capable.

[Wei240]

specR t28 eh? LOL -- all the s15 turbos are the same ;) but ur smart not boosting much more -


not all s15 t28's are the same, there was that other thread showing aussie/jdm s15 turbo differences, i may be mistaken, but some may not even be ball bearing (some quirky aussie version), gotta look at that thread again...

and the non spec r doesn't have the exhaust divider thingy

[koukimonster139]

its called divorced chamber. divorced like my parents:sadwavey:

seriously tho on my s14 SR, track is 16psi, daily down to like 12. works great for me. thats with s15 injectors, fmic, walbro bla bla bla etc..

[HKsilvia]

stock boost ftw
but if u wanna max it out withoout changing internals and keep it from blow turbo, 14 is ur best bet

[Flybert]

specR t28 eh? LOL -- all the s15 turbos are the same ;) but ur smart not boosting much more -

flamebag - u want to get bigger inj before turning the boost up past 10 on your s14 motor... your turbo is a t28 as well, and the 370s arent capable.

Not all s15 turbos are the same. Do your research before you spout out incorrect information.