Originally Posted By 68LAR
Originally Posted By Thumperdart
Originally Posted By 68LAR
Been thinking about this. Say you run a PCV and either want to eliminate it or install a jet to restrict it a bit. How much of a change to the primary jetting is necessary to compensate for the richer mixture? (pcv is a calibrated vacuum leak) I'm assuming that this would only apply to the primary side of the carb, as the secondary should not be affected because the pcv would be closed due to the lack of vacuum, or not affected if the pcv is eliminated all together.


I just went from .040 to .042 ifr's in my 1200 Dommy and that was the ticket to get the mixture screws closer to the 1 1/2 zone instead of 2 out which was still a bit lean........... beer


I'm not as smart as you when it comes to carbs. I run a 4500 1050AN. My IFR's are .036". IAB's are .073" and the HSAB's are .033". Main jets are 85 and secondaries are 92. My mixture screws are out about 7/8's of a turn. Almost one full turn. No holes in throttle blades. I don't see how the IFR's would affect the mixture screws. They work the transfer slots.

When you use IFR do you mean the idle fuel feed restrictors or the intermediate fuel feed restrictors?
I restrict, make both smaller on my street Dominator carbs, both fuel feed channels on the primary side up


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)