Thread: EFI Tuning

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Roger

Got the plots/graphs to Corey--he hasn't had time to really get into them but did offer a few guide lines--

At cruise in closed loop it should tune to arond 14.7

on accelleration/wot---12.5 up to peak torque area then lean to 12.8 at WOT top end(about torque peak going up towards peak hp)


your picture doesn't show enough of your o2 adapter to tell if your getting any reversion into the exhaust tip---this has been an repeated area that we see--best is to weld a bung into the header merge area

Originally Posted by jerry clayton

Roger

Got the plots/graphs to Corey--he hasn't had time to really get into them but did offer a few guide lines--

At cruise in closed loop it should tune to arond 14.7

on accelleration/wot---12.5 up to peak torque area then lean to 12.8 at WOT top end(about torque peak going up towards peak hp)


your picture doesn't show enough of your o2 adapter to tell if your getting any reversion into the exhaust tip---this has been an repeated area that we see--best is to weld a bung into the header merge area

Thanks Jerry,
On the O2 adapter, it's a piece of 1.75" tube that fits over a matching center core in my header, and the outer baffle plate is solid so everything flows through that center core tube. The O2 sensor is 7" from the end of the adapter pipe, so I don't think it can get much reversion, but if it needs to be longer I can weld on another section of pipe - it fits on the passenger header and blocks opening that door anyway, so longer is OK. My narrow band that feeds the ECU is in a bung just after the last primary joins the megaphone, about 15 to 16" from the outlet, plus it is baffled.

Thanks for the numbers on A/F ratio. I will put my wide band back on and go check it at the upper end - I may be a bit leaner than that at the top end, which would explain a slight stutter at about 5500rpm yesterday. I'll look forward to Corey's comments on the spark map.