I've decided to up the boost on my AP2 and wanted to see what size pulley AP2 SC owners have run w/o any internal mods.???

So far I know of 2 AP2 owners that raised the boost:
1. Silver S2k4: 12psi pulley and 750cc injectors and EMS (I think he tried going to 13.5 psi and had some issues)
2. D-S2K: 9.5psi and 550cc injectors and EMS

From what I learned concerning pullies and the AP2 is that a 9psi pulley (3.5") will only push around 7lbs, so my question first is:

1. How many lbs of boost can you run on a SC AP2 w/ no internal mods? (assuming I have EMS and 750cc injectors (that's more than enough right?)
2. What size pulley do I need to get the above boost (so if you state 10lbs would be safe, what psi pulley and what diameter?)

Any input would be helpful, but if you do have an AP2 and increased the boost please leave your specs.

Thanks

 

I second the above question.

 

No one else SC w/ higher boost?

 

my ap2 has 10 psi pulley from www.scienceofspeed.com. it is a 10psi pulley and it boosts 10 so i dunno wut u are talkin about. im runnin aem ems and 550cc injectors. 550cc is perfect for the 10psi setup and im pushing 342.7 to the wheels... let me know if u need more help.

 

i was informed by another member that has done several different pullies that a 7,9,12 lb pulley that were made originally for the AP1's wouldn't really boost those #'s. Basically a 9lb rated pulley for an AP1 would only boost 7lbs or so. Do you know what the diameter of your pulley is and was it specifically made for the AP2?

Thanks

 

well all i can tell you basically as an ap2 owner, is if you want maximum boost on stock internals get the science of speed 10lb pulley. call them and ask them for it and when you put it on the dyno it will pull exactly 10psi as it should be. there is no such thing as a 12lb pulley from any other company unless it was custom made. 10 is the max you can go on stock internals with the ems and injectors. if you intend on boosting any more than that, consider your headgaket blown in no time.

 

Ok let me clarify this. BumpinS2k is reaching the indicated 10psi because his car is tuned for an 8900rpm redline. An AP2 with 8000rpm redline would not achieve this boost.

 

Thanks for the info. I think Silver S2k4 ran a 12lb pulley w/o any internal mods. and it probably was custom made. But thanks for the info. concerning your setup bumpins2k, I think I will also go with the 10psi pulley to be on the safe side. Other than EMS and 550 injectors did you change anything else (sparkplugs, etc...)?

folex187 or bumpins2k: how do you raise you RPM's to 8900? EMS can accomplish this?

 

Silver S2k4's engine is no longer with us.

 

my setup is...

COMPTECH SUPERCHARGER WITH AFTERCOOLER
SCIENCE OF SPEED 10 PSI PULLEY
SPEARCO FRONT MOUNT RADIATOR
MUGEN THERMOSTAT & FAN SWITCH
RC ENGINEERING 550CC FUEL INJECTORS
GREDDY TYPE S BLOW OFF VALVE
AEM ENGINE MANAGEMENT SYSTEM WITH UEGO
INVIDIA STAINLESS CATBACK EXHAUST SYSTEM
T1R TEST PIPE
J'S RACING 4-2-1 HEADERS
NGK-7173 RACING SPARK PLUGS GAPPED 0.032
COMPTECH FLYWHEEL
ACT PRESSURE PLATE
00-03 CLUTCH SLAVE CYLINDER

yes with the EMS u can raise the redline and also engage vtec at much earlier RPMs. my tuner tuned it so my vtec hits around 4000-4200rpm and tops out at 8900 on the dyno. i will scan my dyno and show you once i get a hold of a scanner.