i am running OL for now. tried it fall of last year and it improved idle quality and the WB showed stable A/F rather than erratic logs. plus allowed operation richer than NB02 allows.


not related to OL operation i believe, but i find a dead spot on throttle at 1500 rpms and onset at about1600. i have manual trans with overdrive(4+3). regardless of gear if i hold 1500 rpms the engine has zero power(TQ). seems to stumble keeping set speed. it requires AE to get off that spot with a quicker TPS movement. if i try to accellerate very slowly out of the dead spot it struggles. any gear. any other rpmabove 1500-1600 it accellerated nicely without a lot of AE needed. same with accelleration from standing stop. AE is always involked and all is well. that is unless i allow it to hang at 1500 too long.


when i datalog(CL) i see BLMs in that cell (1500rpms/50-60 map) at around 124. i think i have adequate fuel in those cells and at higher map 1500-2000 as i transition to higher map.

i am thinking it is cam related. 224-230@ .05 114 LSA. comp "computer" cam.

gears are stock 3.07.

timing at idle is 21 and it transitions to about 26-27 during event.

WB died last fall so have not WB logged lately. i think it showed lean during that event.

is this "classic" reversion?

 

The *mandated* 14.7:1 AFR has nothing to do with keeping the engine happy, it's just for the cat(s). Might try adding some fuel in that one spot, or pulling a little timing out, to try and clear it up.

Reversion normally happens at about peak torque.
1,500 RPM is probably just when the motor is starting to make some torque, and just needs some more fuel. It's being peakier....

 

will add more fuel. that will be an easy fix. need to set a new sensor for WB. running blind now..