Holley carb question, part # 80457S


New Member
Jan 24, 2003
Got a good deal on this new carb. I'm running
a 302 w/Comp cam XE250h, auto transmission, slighty
ported heads (according to p/o of this engine),
with roller rockers. The carb had 65 jets, went to
62 jets because it was too rich.(64 jet was what it was suppose to have)I know it's running lean because it acts like it's starving now. Could running too lean have the same effect as running to rich & affect
mileage? The reason I ask is I had an Edelbrock 1406
on there with stock setup & I got around 20 mpg, now I get about 15 mpg. I hope this makes sence.
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