proform secondary guidance

I picked the 3.5 power valve because that was what half my idle vacuum was in drive, per Holley's suggestion on power valve size.


Holley has been wrong way more than they were ever right. You set power valve opening from cruise vacuum and set your cruise A/F ratio with the main primary main jet. Set your WOT A/F ratio with the PVCR and secondary main jets.

Bet Holley never told you that either, because I've never seen them put it in writing.