Quite true, but also keep in mind the use of the decompression gasket and camshaft. The real killer in a turbo engine is high compression pistons, which is why the evo is what, like 8:1? The lower the compression, the higher you can crank the boost before you start frying stuff. So rpw's decompression gasket allows you to lower the compression a little bit in favor of more boost.

Secondly, the camshaft really opens the engine up and allows it to breath easier, allowing for SLIGHTLY more boost, maybe a pound more, but still, every little bit helps.

 

well ya, i didnt think i needed to point that out as they were already being discussed in this thread.

 

wow i didnt think that was on stock compresssion... that is even more amazing... but like dave says its all in the tunning...

and dave i would get one... but im keeping the lancer n/a... one of these days when i get my cc payed off i will be ordering a few things from you

 

BigT-28 comes from Garrett. It came in the box sealed and packaged. It also has Garrett tags on the turbo. The difference is that the BigT-28 is a T-28 with a larger compressor wheel.

 

actually hotshot... i think you both are right... its a t28 with a larger wheel (t3 or 4 i believe)... but it is NOT made by garret... it is put together with garret parts at forced performance...

 

nope, kinda. go to atpturbo.com, an AUTHORIZED distributor for garrett. you will not see a DSM flanged exhaust housing nor a "Big T-28" on their site or on any literature specifically from garrett. the Big T-28 is a garrett turbo originally with all the tags, bells and whistles. ForcedPerformance takes this turbo and sticks on their wheels and turbines to specifically suit the DSM crowd. go ahead and take a look. check all of garrett's distributors as well.

 

I know all this. so what you are saying is i can run 12lbs with proper tuning? Im going to get it dyno tuned regardless, but EVERYONE keeps saying 9 is the limit.

 

here's a a brief discussion on the subject.

https://www.evolutionm.net/forums/sh...d.php?t=140363

 

I don't know who everyone is, but I'm not a member of that bunch. I think you're thinking of what it's safe to run on the RRM Stage 2 as it's sold. Or at least what people say is safe. I don't know that anyone has actually tested or tried to tune beyond that.

 

Probably. This guy is shootin for 18psi with forged internals!

 

With decompression, proper timing, strengthened valve stems and retainer clips, and a slew of other precautionary mods...I see no reason why it couldn't be done. I think omarboy is running around 18psi max.

 

thats fine, all i was trying to get at was that it is in fact a Garrett turbo, and it's a T-28, not a T-25, that's all.

 

I believe that Marc (imapunkclaimer) has been running 11 psi on his rrm stage 2 for a while now. I'm not saying it's safe, so if you have rrm stage 2, don't go turning up your boost. i'm just saying that I think he's been running fine @ 11 psi for a while now on the RRM setup. i was running 9-10 psi HARD for a long time until my fmu decided to take a ****. I'm going to fix everything and i plan on running a hard 9 psi up to redline, all day, everyday.

 

Garrett, yes. The CHRA for both the GT25R and the GT28R are the same so it really is neither if the compressor and turbine wheels are different. i just checked it. we're both pretty wrong in saying it's one or the other. i just sorta got stuck on the GT25R CHRA since you can't order a GT28R CHRA and they share the same cartridge.

 

i got lost. who's shooting for 18psi?