Higer Octane with more boost...

[rn240sx]

Here is my current setup:JWT ECU with 370cc Inj and Stock MAF and 93 octane pump gas, STOCK INTERNALS and 43k miles on my ka24de.Im reading 8 psi solid at the manifold, through out the rpm range and all gears.If i were to fill my up my gas tank with race gas, which i think is up at 103 or something, ( its been a LONG time since ive been at the drag strip so i done forgot ), how much more boost can i run safetly..??Keep in mind that i an running OPEN dump on my wastegate so i CANNOT hear if i am detonating..!!! Im in the process of trying to figure a way to dump it back into the exhaust stream to quiet it down when i go wide open throttle...

ThanksRobert

[C-Kwik]

Only to a point. Higher octane will giove you more detonation reistance. So you can run a leaner mixture, but even on high octane fuel, if you run too lean, it will detonate. With 370 cc injectors, you are still limited to the fuel injectors' capacities. I would go towards race fuel for the purpose of increasing boost only if the avaiable fuel at pumps kept me from using higher boost. I think your limitation will be the injectors. Perhaps I might run race fuel on track days only to be on the safe side, but I wouldn't plan on increasing boost. Only giving myself a bit of a safety net.

[Checkered-Member]

It sounds that you are looking for a bit more power, if you put race gas, instead of turning up the boost, you can run more advanced timing which will result in more power.

[klattr1]

It sounds that you are looking for a bit more power, if you put race gas, instead of turning up the boost, you can run more advanced timing which will result in more power.

Yeah, but he's running a Jim Wolf ecu. Timing cannot be added unless he's using a E-Manage.Just wait and go to the dyno. I wouldnt think you would blow your motor but I dont even know what your air fuel ratios are right now at 8 psi.When I dynoed, I started at 14 psi, then 15, 16 and 17 psi and my air fuel ratios did not change one bit.I would say it depends on your current air fuel ratio whether u should raise the boost 2 or 3 psi.Dont listen for detonation. Know before you boost too high that you wont detonate. All it took was one time for me "listening for detonation" at 15 psi and my forged JE pistons took a dump. I didnt know my previous air fuel ratios at 10 psi and I took a risk. Learn from me!

[WDRacing]

I always used the MSD knock meter, audible detonation is very bad, cause its already damamging your internals. However, you can turn up your boost quite a bit with higher octane, you just need to confident if your tuning. I wouldn't do it without a knock meter. I ran alot of alcohol on my Skyline and was able to raise the boost quite a bit. But I also blew a few motors cause I raised it to much or didn't add enough alky.

Here's clip from Kenne Bell,

BOOST - Both higher compression ratios and boost increase cylinder pressure and demand higher octane fuels to eliminate detonation. Fuel octane determines the amount of boost an engine will accept. Kenne Bell runs 6-7 psi on all our Ford, GM, Chrysler and most other kits with our Twin Screw superchargers. One octane will support one psi of boost. Example: If fuel octane is 94 or you add a can of NOS Octane Booster you can typically run 8 psi

WD