get the s15 t28, cheaper and easier to work with. trust me u dont need/want more than 350whp. also you need bigger than the 550's and i would also higly suggest a new hg and studs, you should be fine with stock cams though, but def new hg

 

I struggle with this too. An s15 turbo will cost ~800 and I cna get a gt2871r for $900. Meh get the 2871R

 

2871r is just as good as an s15 turbo but you might at least get some warranty for the 2871r if you buy it direct. s15's are usually used so there's no warranty with it. my friend has an s15 t28 and he loves it but he says that the 2871r can be good for higher horsepower more thatn the s15 in general but it all comes down to the tuning. so my vote is the 2871r.

 

yeah i have the s15 bb t28 and after a while u might wanna go to more hp so u would me kinda disapoited in not paying that extra 100 dollars.... but the s15 is still a great turbo

 

thats about what i thaught, because i dont want to keep switchin stuff out, but with the gt2871R i really dont need to build it and have it so high on hp though, low boost would be fine for me, 8psi would work for me.

 

Hey

sddrift, just curious you on the san diego drift board, www.sddrift.com?

 

unless your gunna drive the gt2871r with higher boost like 15+ dont waste your time.... my gt2871r is a .64 A/R and the wastegate is set 12psi ... it feels slower than my t25 at 14psi becuase of spool time. but when u bring it up to 20si its a diffrent world.

have you maybe considered the Forced Performance bigt28. they used to be like 650$ bucks but i just checked the site and now its like 800$ :eek4:

but they make like 350rwhp i heard and spool like stock almost and they are a true bolt on ... more bolt on than a s15. u wouldent need anything new except gaskets

 

I'm running a FP Big28. It's worlds quicker than the stock T25. Turbo is fully spooled at 3200rpm and it does pull hard straight to redline. My stock T25 didn't even start spooling until 3600 rpm. Turbo is supposed to be good to 22psi and hold 350hp, but I think that would be stretching it's limits IMO. Though you can most definately break 300hp no problem with it.

 

would it be safe to run the s15 without a metal headgasket?

 

how about forced performance Big28 turbo, i heard that turbo could reach those power goals with very little lag.

 

how does a turbo determind if a car is able to daily drive? WTF?

staygold24, it depends how much power you're trying to make out of that turbo. if you're aimming for over 330whp, i suggest a metal head gasket.

soawsome, simple, the flow rate is much different at 14psi on a t25 and a gt2871r. the sweet spot for a 2871 is around 18-22psi.

 

soawsome, simple, the flow rate is much different at 14psi on a t25 and a gt2871r. the sweet spot for a 2871 is around 18-22psi.

ya i know that im just trying to keep it simple.

 

You can also get the Disco Potato... It's a step below the GT2871R...

 

will if anyone has a gt2871r and want an s15bb ill be more than happy to trade ya!

 

definitly go the 2871R. stock HG is fine and 550cc injectors are good to 350whp. with stock cams you wont get much past 330whp anyways. get a Enthalpy Tune too. I run the Enthalpy Tune and 2871R .86 on the stock HG at 19psi with no knocking and powers near 375+whp. Its been that way since May.

 

Dopple, when do you hit full boost again? I am still debating between the .64 and the .86. But to the original poster, go with the 2871R. If you are going to upgrade, you might as well upgrade a little higher than your goals just in case you want more power.

 

I used the .64 with the stock turbo elbow and saw 19psi around 4krpm. With the .86 and Greddy Elbow i see 19psi around 4200rpm. Only lag i see is below 3500rpm. I drag race anyways so im always 4krpm or higher where boost is on right away.

 

how significant is the power increase over the .64? At least what you can feel

 

Its somewhat noticable but my setup isnt maximizing the .86 like it should. I think the "record" for the .64 is 377whp and the .86 is 427whp. The .64 record was done with stock Intake Manifold, Greddy Elbow, 650cc Injectors, Enthalpy Tune, and JWT S3 Cams. I believe more power could have been made with a Greddy Intake Manifold. The .86 record was with Greddy Intake Mani, 740cc Injectors, Greddy Elbow, Enthalpy Tune, and HKS 264 Step 2 Cams. The same guy with the .86 made 411whp using HKS 264 Step 1 Cams and then switched over to the Step 2's. I might be around 370-380whp. I still need a Greddy Intake Manifold, 740cc or larger injectors, and larger cams to really maximize power. Power difference between the two is probably 50-60whp and 400rpms later. I dont drift anymore so i chose the .86.

 

Like someone said, why not go with a disco potato? Isnt it in between in flow rate and actually spools the same or faster than the S15 turbo?

Just a thought.

 

I say go with the big28. You end up saving a little money, and it supposedly spools up around 2500 rpm if i remember correctly. Thats what I eventually plan to do. Although, I have a friend that runs a gt2871r daily at 20lbs. No problems for him. Car does great, and is fast as hell. You won't need a new headgasket necessarily. It's always a good thing, but your engine should be able to handle it fine. He's been running stock internals for a good year now with no problems.

 

The main question that needs to be asked here is, what do you want out of the car? And what do you want to do? Many people have given great advice but, it's all on you. If you're doing drag and highway racing go with the .86. If you're more into road racing and auto-x go with the .64, as it will come on quicker coming out of corners. It's all about what you're goals are for the car though. I'm going to go with the GT2871R .64 as I want some streetability from it.

 

How about the GT28R they seem around the same price as the s15 turbo?

 

There priced the same because they are the same.

 

Sorry buddy but they are the same.
ATP Specs on Garrett GT28R
Phase 2 Specs on S15 GT28

 

ok thanks, i'm looking for a good driver car that i can drift and drag, i think i'm going to go for the s15 because i dont want to run that high of boost for how i drive and possibly hurt my engine...its a future thing anyways for winter. thanks

 

im still lost why you would go 28R over 2871R because of boost reasons? you can run 16psi on the 2871R and get over 300whp where the 28R is gonna need close to 20psi to achieve the same power.

 

i would like to here more about the FP Big28

 

Id like to see a dyno chart on the FPbig28. I remember seeing one a while back from Hybridynamic and it made a little over 300whp @ 18psi i think. They were dissapointed with it but they also said the wastegate was acting funny from the stock actuator. I remember the torque curve peaking really early and had a quick decent downward to redline. I see a good bit of people get around 330whp from it on stock cams and intake manifold. Im sure there is more to gain once Cams are upgraded.