L67 Question

[Miko K]

yeah i have heard some people retune for mid grade on this engine. and when they go to the track they switch to premium. but yeah the highest grade is deff worth it. normally top fuel is only $.2 more! so even at 16 gal... thats $3 ? is that worth replacing an engine? esp after spending $$$ on mods.... to only destroy it.

 

yeah but the SC can not turn off. it does have a Boost Bypass Valve. BBV but that is just for low RPM. basicly at low throtle it acts like a NA car. and then at higher throtle it opens and runs on boost

I was refering to the Boost Control Solenoid, as a method of controling the boost, it opens the bypass valve via the pressure port to bleed boost back behind the throttle body.

[dbtk2]

In the PCM itself there is two separate "main spark advance" tables- high and low octane. When the PCM detects too much KR it simply sends you to the low octane table until you get pass a KR threshold to get back to the high octane table. In the "Torque management" window there is a sub-window for "supercharger torque management" that controls the boost if you are beating on the car and KR doesn't help. Hope this helps.

 

Exactly. The PCM will see that it is getting too much KR, and therefore assume it has low octane gas, and refer back to the "low octane" timing tables. Also, after a certain amount of KR, it will open the boost bypass valve to dump boost as a last resort if you are still getting a lot of KR. So it does have methods of decreasing boost to try to save the engine, but it can't completely "turn it off".

[dsgrntld187]

Don't worry guys, I always use 93+ in it. This was a completely hypothetical situation, I have no idea why it came up anymore even.