The O2 feedback system controls part throttle, and the pre programming in the computer controls full throttle mixture.
So the filler neck MAY have influence.
Rich runs cooler [it's the ONLY reason for rich/lean knock differences], but going a bit lean is not always going to produce spark knock. Many power programmers for chips and computers are leaner than the factory.
Anyways, you need that filler fixed for a bunch of other reasons!
So the filler neck MAY have influence.
Rich runs cooler [it's the ONLY reason for rich/lean knock differences], but going a bit lean is not always going to produce spark knock. Many power programmers for chips and computers are leaner than the factory.
Anyways, you need that filler fixed for a bunch of other reasons!