Forced Performance turbo

[Supafly]

I believe that the compressor only comes in one trim and flows 44lbs/min. The option is to get either a .64 or .86 A/R on the turbine.

Someone please correct me if I am wrong.

Also we may need to start a new thread. I feel like we are thread jacking on the FP turbo.

i've seen it advertised with 2 different compressor wheel trims, 42 and 58 (or was it 48 and 52?). they flow 39 and 44lbs/min respectively according to the site i found the info on.

and to the person that asked about the A/F on 50lb injectors and 93 octane, it was nicely between 11.5-12:1 pretty much all the way along the graph. i have no clue his fuel pressure settings or injector duty cycle at that level but i'm sure it's pushing the fuel system to it's outer limits. but the wideband doesn't normally lie;)

as for the bigT28, i've seen it make about 325whp but that was pushing it pretty hard.

[VitaminT]

Cool. I am looking to get the one cheapturbos.com sells and it says 44lbs/min.

[candela]

Quote »At least 15hp I hope? How much boost can a big28 run?[/quote]

At 8psi i am sure you will probably make more power on the T-25... Larger turbo's are efficient up higher. Bigt28's are pretty good from about 16-20psi..

I have seen people running ~22psi but I can't imagine that its that efficient up there. With good cams, fmic, fuel and exhaust/tuning that turbo can do 300+whp

[Supafly]

Cool. I am looking to get the one cheapturbos.com sells and it says 44lbs/min.

yeah that's odd, the other site i saw listed the 48 trim wheel (what cheapturbo specs on their site) as flowing 39lbs/min and the other trim (52 or 56, i wish i could find the site again) at 44lbs/min.

[240SXer]

I'm gonna have to run only 8psi till I upgrade my fuel system. I still want to put down decent power in the interm. Will it put down as much power as a T25@10psi? 9?

[Supafly]

At 8psi i am sure you will probably make more power on the T-25... Larger turbo's are efficient up higher. Bigt28's are pretty good from about 16-20psi..

I have seen people running ~22psi but I can't imagine that its that efficient up there. With good cams, fmic, fuel and exhaust/tuning that turbo can do 300+whp

the bigger turbo should make more power at the same level of boost. it may not be in it's efficiency range, but it is still flowing more air per psi of boost than the smaller turbo.

[240SXer]

about how much more power though?

[VitaminT]

yeah that's odd, the other site i saw listed the 48 trim wheel (what cheapturbo specs on their site) as flowing 39lbs/min and the other trim (52 or 56, i wish i could find the site again) at 44lbs/min.

Haha, this site lists the 48trim with 48lbs/min

http://www.gcg.com.au/catalogu...tml#3

Here is a site that corresponds with the info you are providing. Note that is says that the Compressor is a T35 not a T04s.

http://www.extremeboost.com/sp...t.htm

[candela]

Quote »the bigger turbo should make more power at the same level of boost. it may not be in it's efficiency range, but it is still flowing more air per psi of boost than the smaller turbo.[/quote]

Negative.... I will go extreme here, but what do you think will make more power a at 8psi on his system; a s14 turbo or a t4 Q trim (MUCH bigger) that does NOT get in its efficiency range until higher speeds. Do you know how to read compressor maps? If so email me and I will send you some of t25 vs. t28 and point it out to you.

Quote »I'm gonna have to run only 8psi till I upgrade my fuel system. I still want to put down decent power in the interm. Will it put down as much power as a T25@10psi? 9?[/quote]

The t28 isnt much larger, and the difference is very minor. If you are going with a Bigt28 you will notice the lag of that turbo when compared to a t25 at 8-10 psi and you will most likely be making a little less peak torque. The HP may be close to the same or possibly more if you wind out the RPM's (t25's cant push very far), but overall dont expect anythign much at all. ALthough its ok to run ~10psi on the stock fuel system (with a larger fuel pump that is) on the T28 and be ok. I used to run ~12-13psi on my s14 turbo with 255lph and FMIC and the A/F was fine (little lean above 6k) as measured by a wideband on 91 pump.

[Supafly]

Haha, this site lists the 48trim with 48lbs/min

http://www.gcg.com.au/catalogu...tml#3

Here is a site that corresponds with the info you are providing. Note that is says that the Compressor is a T35 not a T04s.

http://www.extremeboost.com/sp...t.htm

yeah i think extremeboost was the one that i saw that info at. lots of good conflicting info out there for that turbo it seems, lol.

and to candela, in your extreme example, you're probably right. but a T28 isn't that much larger than a T25 in overall size and i do believe it will make more power (especially on top due to the larger exhaust wheel) at equal boost even that low.

[candela]

Quote »The t28 isnt much larger, and the difference is very minor. If you are going with a Bigt28 you will notice the lag of that turbo when compared to a t25 at 8-10 psi and you will most likely be making a little less peak torque. The HP may be close to the same or possibly more if you wind out the RPM's (t25's cant push very far), but overall dont expect anythign much at all.[/quote]

ya thats what Im saying, i agree about the horsepower thing, but it will be VERY minor :ylsuper

[AznRide]

I don't know which turbo I want to get. I just want a bolt on, but really want the GT25R. The Big28 (see I mentioned Big28 so I'm not thread jacking) is a bolt on, but not much HP gain from the stock T25. In the other hand, the GT25R has a hugh amount HP gain, but according to Zfever.com and other sites, they said something about shaving the turbo because it would interfear with the engine mount...does anyone know what the hell to do if one does get the GT25R???? I'm trying to get a hold of Paul and hopefully he can answer me but he seem to not answering his AIM, even though, he's on constantly.

[VitaminT]

You have to trim the driver's side motor mount bracket. See link.

http://store6.yimg.com/I/phase...43851

You have to cut a small C-shaped cut in the bracket. Note that I do not speak from experience, but only from what I have read getting ready to put one on my car.

[AznRide]

Ahh, I see. That bracket is steel, that would take some time shaving that off...Thanks Vitamin...T? Is that suppose to be a 25mg T? If so, I want some of those...oh snap back to reality, oops there goes gravity...uhh

[VitaminT]

Yeah, you could probably use either an angle grinder, bench grinder or sawzall.

I think the angle grinder would take too long and probably the bench grinder too so I will probably take the sawzall/hacksaw to it in a few months when I have everything compiled to do the turbo upgrade. I figure I might as well P&P the head along with a 3 angle valve job while I am there.

[AznRide]

what about the wastegate?

[VitaminT]

They are internally wastgated. You have to custom mount the actuator though. Not sure how I am going to "rig" up that yet, but it has a flapper door in the turbine housing.

[180crafter]

surprised no one asked, but 300 hundred bucks for one of these??? How is that? I would love to jump on a deal like that!

[AznRide]

yea...me too, it looks sweet also...but most people that does SR swaps or whatever with 240 are low budget racers so 3 bills probably cost them an arm and a leg if they are still in high school or whatever...

[IowaSilvia_S13]

I have a FP Big-28 and love it to death..........i'm running 12 psi. don't know what my hp gains are. but way better than stock t25

[240SXer]

Cool.. Was it totally bolt-in?

[180crafter]

$300 is still better than $1300. Im not too budget, but do like to jump on a good deal when I see one. I wouldnt mind putting down 300-500 for a turbo that has that good of a rep, while I build up other aspects of the car.

[drivewaysk8er]

so then does the big t28 bolt-on? also, what was that $300 deal? that sounds like an awesome deal.

[Boardman]

The Forced Performance Big28 is the stock SR20DET T25 turbo THAT YOU MAIL TO THEM then they re-work it's internals AND MAIL IT BACK TO YOU.It will fit exactly like it did before.

For the GT25R you need to add the price of custom oil/water lines, fabbing a wastegate to fit on(probably want to purchase a HKS unit), fabbing a 4in. air intake elbow/silicone connector <-- can get expensive.Just something to think about because these extra costs/labor/headache are never mentioned.

[Gladius]

I believe you can use stock oil and water lines. My proof would be what movingviolation240 did. Check it out here.

http://www.nissaninfiniticlub....53883