T28 boost question

[pearlS13]

Hey guys, i'm picking up a t28bb turbo and was wondering what the safe level of boost is for them. I know for a t25 you shouldn't boost over 15psi, what about the t28? I'm getting upgraded injectors/maf and im hoping i can hit 300rwhp with the t28. Is this possible without maxing out the turbo?

Also, is there a way to identify if it a bb or non bb and if its a s14/s15 turbo?thanks.

[Blown240sx]

I believe the T28 has the same limits. The only real advantage you will see is the BB turbo will spool easier than the others.

[89'ClubK's]

The S14 Turbo is a T28/25 hybrid style. The S15 is a straight T28. Both a BB.You should be able to see 300 whp. with these turbo's w/ injectors and boost increase. Ball Bearing turbos' do spool faster, but I hear they don't last as long, and need rebuilt every 50-60K. miles. I'm using the S14 on my CA18, and will try to get around 250 whp w/ boost increase, so your #'s seem good for the SR. Good Luck!

[highmilehatch]

The S14 Turbo is a T28/25 hybrid style. The S15 is a straight T28.

S15 and S14 turbos are exactly the same except for an inconel exhaust wheel and a divider cast into the exhaust housing on the S15 to separate the wastegate from exhaust wheel.

[S2R4200_ONEVIA]

hmmmmmmm

[nzmoman]

this may have been done already but not mentioned. be sure to upgrade the fuel pump. You will be able to boost past 15 psi on the BBt28. But if you get carried away you will be playing in the realm of head gasket problems, around 20psi or so, so be carefull with that. Are you already running a large frontmount intercooler

[pearlS13]

yes i have all the supporting mods needed so im not too worried about boosting 15psi on the t28. I've got a greddy vspl fmic, complete 3 in turbo back exhaust with heat wrapped tubular mani, walbro fuel pump, adjustable fuel pressure regulator, safc2, and some other little bolt ons.I will also be running a z32 maf and 550's aswell. I just wanted to make sure that 300rwhp would be possible with a T28.

[highmilehatch]

You'll be hard pressed to hit 300whp on that turbo with a piggyback. I made 290whp and 310tq on an S14 T28 with 600cc injectors and Power FC @ 18psi. If you want to keep the turbo inside it's efficiency range, keep the boost around 15-16 psi. I've seen an S15 turbo hit 300whp/300tq with an afc however. Not sure of the boost level.
Modified by highmilehatch at 11:48 PM 7/4/2006