Knock Sensors Pulling Timing
04-15-2017, 03:56 PM
#1
Knock Sensors Pulling Timing So I went out to re-tune the car today after adding a 2nd stage 50 shot on top of a 120 shot 1st stage (cold fusion plate). I am getting ready for a half mile event so I was doing 4th/5th gear pulls. Bottle pressure at 950psi and 4th pulls real clean, shift to 5th and its humming until about 5300 RPM when the computer pulls 3, 5, and then 10 degrees of timing. Shut it off, pull over, and then pull #8 plug. No signs of detonation so I put a new plug in and make another pull. This time it breaks up in 4th gear and I shut it down.
Setup is a forged 370 with ported 243 heads running 9.6:1 CR and a procharger at 11psi. These runs were on a 9 NGK plug running E67 gas (flexfuel) and 10.5 gas scale AFR. I locked the timing in at 14 degrees. I almost seems like there is too much heat buildup or the rings are too loose after the engine gets hot causing this to happen. I will post some plug pics later and I still need to pull the other 7 to see what they look like. Any help is appreciated.
Setup is a forged 370 with ported 243 heads running 9.6:1 CR and a procharger at 11psi. These runs were on a 9 NGK plug running E67 gas (flexfuel) and 10.5 gas scale AFR. I locked the timing in at 14 degrees. I almost seems like there is too much heat buildup or the rings are too loose after the engine gets hot causing this to happen. I will post some plug pics later and I still need to pull the other 7 to see what they look like. Any help is appreciated.
