ZR-1 Net Registry Forums - View Single Post - Spark Plugs-Long Story Short

XfireZ51 · 10-03-2018

IIRC, the FR3s are “hotter”, which would make sense since the right side (passenger) seems to run richer than the left, particularly at lower rpm. The disparity between Right and left bank BLMs gets smaller as u climb up the rpm scale. “Split BLMs” aren’t just an LT-5 issue. The ECM is modifying fueling based on an “average” since there is only one VE table for both banks.
My thought would be to run the fuel supply feed in parallel to each of the fuel rails rather than in series. I suspect that u would find that fuel pressure is slightly lower on the left side than the right. The Xfire was like that and they came from the factory w a larger injector on the left side of the motor to offset the lower FP.

10-03-2018	#5
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,685	Re: Spark Plugs-Long Story Short IIRC, the FR3s are “hotter”, which would make sense since the right side (passenger) seems to run richer than the left, particularly at lower rpm. The disparity between Right and left bank BLMs gets smaller as u climb up the rpm scale. “Split BLMs” aren’t just an LT-5 issue. The ECM is modifying fueling based on an “average” since there is only one VE table for both banks. My thought would be to run the fuel supply feed in parallel to each of the fuel rails rather than in series. I suspect that u would find that fuel pressure is slightly lower on the left side than the right. The Xfire was like that and they came from the factory w a larger injector on the left side of the motor to offset the lower FP.