s15 turbo or used t25

[kendal_jones101]

ok i got about $1000 to spend i can get a brand new s15 t28 turbo or i can get a used t25 and have money left over to play with what else do i need for the s15 turbo is direct swap from the t25 or do i have to do more to make it work i heard you cant run more than 9psi or the maf will max out and run lean can someone help me out with this what do you guys think would be the best choice........

[Hijacker]

You will need supporting mods to make the S15 turbo not blow your car up. IE injectors, MAF, and ECU. The stock setup pretty much tops out at 250 hp all around. I would be hesitant to run the T28 over 7 psi just because of the fuel injection limit.

If it were me, I would get the S15 turbo, but I would be damned certain to get the fuel system upgraded ASAP and stay off the boost as much as possible until then. The only reason why, is I have yet to see a T25 that doesn't take some sort of crap after some time.

[moulton712]

i did have a huge question about this topic, but i was going to ask when i have more funds (i'm about done with my white s13). i was looking into a t28 for my red s13 with an sr. stock injectors. i know what you are saying about problems with the stock t25's. it's cause they have barrings which can gum up even if you grandma the car it's whole life.this is what my problem is. i can hear the turbines come into contact with the turbo housing. i need a new turbo.

the stock wastegate on the t28 is 10 pounds.

what do i really need to convert over to the t28 from a t25?

i have installed and running perfect:

greddy emanage ultimatewalbro fuel pumpo2 widebandhks boost controllersome other stuff... lol

i was just thinking i would just need the s15 t28, new exhaust manifold, possibly a new down pipe (i believe it's not stock), and re tune. what else would i need?

i'm seriously looking at doing this within 2-3 months.
Modified by moulton712 at 6:18 PM 6/6/2008

[virus77]

Ive got a used s15 turbo from my car i want to sell because im going topmount, you can have it for $550 including the outlet pipe and custom intake pipe I had on it Still in great condition, boost perfect

[Hijacker]

You can reuse the stock manifold. The turbine uses the same flange between the T25 and T28. The outlet pipes are slightly different. One of the bolt holes doesn't line up properly, but it's easily elongated to make it work right. Or if you have a T28 outlet pipe, you're good to go.

There are adapter brackets sold now that you can use to make your stock T25 intake plumbing work with the T28.

You REALLY really need upgraded injectors to make things run reliably. The stock injectors are maxed out on reliable flow at the 250hp mark. To get past that, you really need to upgrade them.

[supreamS14]

Dont boost 14psi ! I creeped to 18 psi AND...

[burntricer]

im now running a T28 from a s15 on a stock Sr. 7psi no problems. boosts fine, but i wont turn it up past that until i install my cams, my Emance ECU ect

[moulton712]

You can reuse the stock manifold. The turbine uses the same flange between the T25 and T28. The outlet pipes are slightly different. One of the bolt holes doesn't line up properly, but it's easily elongated to make it work right. Or if you have a T28 outlet pipe, you're good to go.

There are adapter brackets sold now that you can use to make your stock T25 intake plumbing work with the T28.

You REALLY really need upgraded injectors to make things run reliably. The stock injectors are maxed out on reliable flow at the 250hp mark. To get past that, you really need to upgrade them.

thank you.

very good info

i figured i'd get a new manifold to an equal length, so i can be even more efficient.

honestly i don't want to go too much past 250 but i do need a turbo upgrade. (more power - more upgrades) i'd stay about 7psi. i never use my boost controller. it's an hks electronic one. i don't feel the need to go crazy around town. this is why my white s13 is having issues and needs to be freshened up. (runs perfect but feels like it's slowing down. and yes i am ridiculous about maintenance.)

[kendal_jones101]

yea iam gonna pick up another t25 and tuned ecu from ebay a friend just got a nasty old school tuned ecu his car has a t25 and ecu and it moves out

[mistamacadamian]

250 really isnt all that much. you say it cost more to upgrade for more power? it just cost more for reliability, as in a safe set up. nothing wrong with having a nice 300hp machine. you can hit 300 with a t28, 17psi, intake manifold, 480's, fuel pump, and JWT ecu for sure. make low boost 10, then 17 for when your running some modded cars. but then again saving and sacrificing some money to beat porshes and bmws and mustangs is just me....and buy a used s15 turbo, that guy offered to sell you his so if its in good condition go for it.

yea iam gonna pick up another t25 and tuned ecu from ebay a friend just got a nasty old school tuned ecu his car has a t25 and ecu and it moves out

t25's move...but slow lol you'll be lucky to run with srt4's if they have a decent driver.
Modified by mistamacadamian at 7:22 PM 6/7/2008

[moulton712]

well i'm saying reliable 250hp. i'm pushing 254hp @15 psi, but 207hp @8 psi. torque is about 5-10fp higher than my hpi want to be pushing about 250hp @7-8 psi this would easily give me 300hp @15 psi.

i just don't want to do a simple upgrade and be thousands. it's not my track car.

[mistamacadamian]

250 at 8psi? t3t4 57trim?

[Clawhammer]

I plan on getting a GT28R w/ HKS actuator, 550cc's, and a z32 maf. What do I need to do as far as ECU though?

[240_SeX]

i want to be pushing about 250hp @7-8 psi this would easily give me 300hp @15 psi.

You wont make 250whp with a t28 at 8psi. going from a t25 to a t28 will not give you 43 hp.....ever

[virus77]

You can get a tuned ecu for that setup, its a very common setup so over the counter ecu tunes are pretty good(enthalpy, E-mance, JWT etc...) You can also get a SAFC or Emanage or some other piggyback to tune for the new injectors and MAFS.<shameless plug> FYI im selling a GT28r with custom stainless intake pipe and intercooler outlet pipe for $550 </shameless plug>

I plan on getting a GT28R w/ HKS actuator, 550cc's, and a z32 maf. What do I need to do as far as ECU though?

[trouble racer]

well am trying to run a t25 on a sr20 stock i just had the swap don on it about 4-5 months ago what do i need to make it work ?

tanks for any help.