Air/Fuel tune needed?
03-09-2006 | 12:44 PM
#23
Another vote for jacked wideband readings as well.
You need to get a scanner hooked up. Look at the
mid throttle, >4000RPM LTFT values (just below the
point where power enrichment kicks in) as a reasonable
indication of the "health" of the air metering and fuel
delivery. On a stock car these should be near zero.
To have a 14:1 delivered AFR with stock tune in PE
you have to be looking at an error on the order of
18% rolled up. That would have to have some other
manifestations. Like persistent KR or audible pinging.
Though stumbling on tip-in is indicative of lean error
in my book, I'd be surprised if an unmolested car was
skewed that badly.
Of course, she -says- she's a virgin....
I'd say pick up a wideband bung (Jeg's, Innovate, etc.)
and spend the $10-$20 to have it welded in the I-pipe
a few feet before the cutout, handy for you to screw in
on the driveway or the dyno (mine is right opposite the
passenger's door trailing edge). Tailpipe sniffing is very
error prone.
You need to get a scanner hooked up. Look at the
mid throttle, >4000RPM LTFT values (just below the
point where power enrichment kicks in) as a reasonable
indication of the "health" of the air metering and fuel
delivery. On a stock car these should be near zero.
To have a 14:1 delivered AFR with stock tune in PE
you have to be looking at an error on the order of
18% rolled up. That would have to have some other
manifestations. Like persistent KR or audible pinging.
Though stumbling on tip-in is indicative of lean error
in my book, I'd be surprised if an unmolested car was
skewed that badly.
Of course, she -says- she's a virgin....
I'd say pick up a wideband bung (Jeg's, Innovate, etc.)
and spend the $10-$20 to have it welded in the I-pipe
a few feet before the cutout, handy for you to screw in
on the driveway or the dyno (mine is right opposite the
passenger's door trailing edge). Tailpipe sniffing is very
error prone.
