ECMlink [Resolved] Knocking, don't know why.

[flinguist]

Car knocks under boost, not sure why.

Running BPR9ES gapped to .024, 93 octane. Wideband A/F looks good. 08.06 log at 70 seconds, 08.09 log at 260 seconds.
ECMLink logs

 

[We're on Boost]

Looks like 13 degrees is just too much timing advance for it on gasoline.
Do you have a boost gauge? BoostEst is going up to 21-22 psi. Is that about right?

You could try it a little richer. The LC1 is saying 10.9 AFR just as you head into the knock areas. Your OpenLoopMaxOct table says more like 9.6 in that area around LoadFactor 2.25 so you are leaner than the table. So you could calculate a new global fuel from a smaller injector size like 900 or 950cc injectors. That would make your global fuel around -50 or -52 or so. Actually instead of doing that, you could just move your sliders on the fuel adjustments table back up to 0. They are at -3.1% now, so they are making it leaner.

 

[flinguist]

I'll give it a try. Thx

 

[flinguist]

Turned out to be crappy fuel. Some E85 and octane booster got rid of problem.

 

[curt-s]

Going from 93 to E85 + booster is a HUGE difference.
What else did you change fuel settings-wise to account for the massive difference in fueling requirements between these two?

 

[flinguist]

It was just a couple gallons of E85 in a full tank of 93 octane, and 15 oz. of Lucas octane booster. A/F's were good.