The "lag" in AFR's
I Did this log today at 9 AM. I shows once again that going WOT in 3rd gear wouls lead to a leaner AFR, than going WOT in 4th gear. We are talking 1.23 points leaner here. The AFR at 5700 was 11.48 in 3rd and a stunning 10.25 in 4th. If we are to extrapolate from this (we should not), then 12:1 in 3rd gear would get you 10.7:1 in 4th gear. This is still rich, but not as rich as 10.25 
I wonder what the AFR would be in 4th gear at 7K 
I wonder what the AFR would be in 4th gear at 7K
Originally Posted by razorlab
Interesting, my car doesn't swing that much, higher gears are richer of course but not that by that much if I recall correctly. Let me try and find some logs tonight...
Originally Posted by nj1266
I Did this log today at 9 AM. I shows once again that going WOT in 3rd gear wouls lead to a leaner AFR, than going WOT in 4th gear. We are talking 1.23 points leaner here. The AFR at 5700 was 11.48 in 3rd and a stunning 10.25 in 4th. If we are to extrapolate from this (we should not), then 12:1 in 3rd gear would get you 10.7:1 in 4th gear. This is still rich, but not as rich as 10.25 I wonder what the AFR would be in 4th gear at 7K
I wonder what the AFR would be in 4th gear at 7K nj was this log started at a 3erd gear pull and ended in 4th gear??
or did you just logged 4th gear? if not you should try and logg only 4th gear to see what happens i think it will be different
Originally Posted by jrsimon27
nj was this log started at a 3erd gear pull and ended in 4th gear??
or did you just logged 4th gear? if not you should try and logg only 4th gear to see what happens i think it will be different
or did you just logged 4th gear? if not you should try and logg only 4th gear to see what happens i think it will be different
Originally Posted by nj1266
That is 3rd gear follwoed by 4th gear. I have yet to find a ramp long enough to allow me to do a 4th gear WOT log
also if you do it please don one starting in 3erd gear then shifitng to 4th gear all the way to redline,then do another log starting in 4th gear all the way to redline and i bet to you that the results will vary please please please do it
!thanks!
Ok, here is a 3rd and 4th gear log from my car from awhile back. It's a long screenshot but there is alot of data. Keep in mind this is from a log that was WOT in 1st,2nd,3rd and 4th, just like you would normally do for full acceleration or 1/4 mile or ripping off one from a stoplight. 
3rd gear - 6086rpm = 11.1 afr - timing = 11*
4th gear - 6018rpm = 11.0 afr - timing = 11*
3rd gear - 6520rpm = 11.1 afr - timing = 16*
4th gear - 6509rpm = 11.1 afr - timing = 15*
3rd gear - 7081rpm = 11.1 afr - timing = 20*
4th gear - 7002rpm = 11.2 afr - timing = 17*
3rd gear - 6086rpm = 11.1 afr - timing = 11*
4th gear - 6018rpm = 11.0 afr - timing = 11*
3rd gear - 6520rpm = 11.1 afr - timing = 16*
4th gear - 6509rpm = 11.1 afr - timing = 15*
3rd gear - 7081rpm = 11.1 afr - timing = 20*
4th gear - 7002rpm = 11.2 afr - timing = 17*
Last edited by razorlab; Jul 31, 2006 at 07:51 PM.