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bdads
04-08-2020, 05:21 PM
hey guys,,, ive been out of the loop for a bit --- and forgot ,,,,
for a larger cam in a 383---1989 firebird tpi-- maf table----
do I adjust to the higher gram/sec to lean this out ????? or do I adjust lower ????
much thanks --- steve 15361

steveo
04-08-2020, 11:41 PM
that one is airflow vs input voltage, so richer is up, and leaner is down.

few things though

- if you smell fuel at idle, just because it's not burning it doesn't mean its rich. it might already be too lean and misfiring raw fuel out the exhaust.
- try timing adjustments too, bigger cams usually need a bunch of timing at idle
- turn your up, even 100rpm can be night and day
- if you want to tune just closed throttle idle, and the rest of your fueling is alright, see if there's a table other than MAF that'll let you do that. there's usually some kind of closed TPS fuel adder.

bdads
04-09-2020, 04:02 PM
much thanks --- I did advance the timing up to roughly 26 at idle --raised all of it-and smoothed the whole range out ,,, all other aspects seem real good ,, and runs great ,,,
just a tiny bit rich at idle now,, not bad enough to worry about-- took a few tries yet I believe its set now !!!! thanks again