GSC 280's installed with dynosheets
 

Hi Guy's

Installed my NEW GSC 280's yesterday, they're great! :D {thumbup}

Low boost 22 psi:

I made an overall peak HP gain of 22 whp and 20 ft lbs of torque on my low boost tune 22psi {thumbup} I was running HKS 264ex & 272in on my previous dyno.

Horsepower GSC = 362whp/318 ft.lbs. torque
Horsepower HKS = 340whp/299 ft.lbs. torque

High boost 26 psi (for now):

I made an overall peak hp gain of 20whp and 29 ft.lbs. of torque...but with some issues. I kept getting a break-up/popping between 6500 rpm and 8000 rpm, sound like some kind of ignition problem. My tuner believe's it's plugs and that they where fouling...my AFR's where in the 10's. I didn't have an extra set of plugs so I had to call it a day. My tuner believe's he can get 420-430whp once that issue is corrected.

Horsepower GSC = 401whp/369 ft.lbs. torque
Horsepower HKS = 379whp/340 ft.lbs. torque

Idle:

I use an autronic ems, my idle is great sounds like an Evo with cams, :lol: very tolerable. I noticed my vaccum dropped to -8 psi and -10psi (with engine fans off)

My impression of these cams {thumbup} car pulls way harder now, top-end feels that much greater. Before I was running 26psi with pump & 50/50 methanol/water and getting 375whp...now I run 22 psi no meth and accomplish same gains. I'll soon retune for 26psi with methanol/water.

Awesome I bet it is fun.

Very impressive.

so they make the turbo spool a lil later and pack 20hp to the topend. How much will you pick up from 7-8000rpms without the break up?

I think you switched the numbers for the high boost setting. GSC made more than the HKS no?

Good numbers!!{thumbup} Post results after u get the issues resolved and retuned

The turbo doesn't spool any later, just got on the throttle later when I was doing the dyno pull, the spool actually feels better and much more linear than before.

Well, I can pick up some extra HP when I lean the AFR mixture some more from 10's to 11.3-11.5 and if the plugs where the problem, they would have killed power somewhat. Tuner didn't want to lean mixture till break-up was corrected.

I think i'll see a bigger power difference will be before 7000 rpm as i run a .63 ar exhaust housing and it kinda chokes in the 7000+ rpm range. With the break-up corrected the curve will smoothing and I might get an additional 5-10 whp between 6500-8000rpm..might.

:lol: Thanks...wrote 'em incorrectly {thumbup}

Nice! I'll be having mine installed and tuned next Wednesday. Will be 50 trim and meth.

Nice!!{thumbup}

https://www.evolutionm.net/forums/at...chmentid=97601

https://www.evolutionm.net/forums/at...chmentid=97602

Nice gains....very nice. {thumbup}

Ang Yen Wang thanks for making the dynosheets bigger for me.

try regapping the plugs to 28 or even 26 if that wont do it you will need a HKS DLI. we had the same problem on our cars above 400whp changed plugs added DLI no more problems.

Thanks for the Review and glad you like them!

edit... the vacumn you're seeing is normal with a larger duration higher lift cam.

I was just saying that on the last large dyno graph the gscs look to be spooling up slightly slower despite hitting the throttle earlier on the graph. That factor makes no difference to me as they make good power up top. The light green would be the gsc correct?

Greg,

I checked my plugs lastnight, they looked PERFECT, so I don't think it was fouling, i'm currently using a gap of .22.

You suggest I try and use a larger gap .28 or .26? I was actually thinking to go smaller/tighter to .20.

Also, i'm wondering if my plug wires might be going bad as breakin up is sometimes a symptom of bad wires.