Anyone know the CFM for the Holley Carb PN 75021?

[AaronWhitt82]

Hey sorry to bug everyone again, but I called Holley trying to figure out what CFM my carb is with PN 75021. They said they don't have a listing for it at all. (Go figure)
I need the CFM to figure out some other adjustments and to set some springs.
I think it is either 600 or 750???

Anyone know?

Thanks,
Aaron

[Engine Nut]

Hey sorry to bug everyone again, but I called Holley trying to figure out what CFM my carb is with PN 75021. They said they don't have a listing for it at all. (Go figure)
I need the CFM to figure out some other adjustments and to set some springs.
I think it is either 600 or 750???

Anyone know?

Thanks,
Aaron

Your carb is a 600 CFM.

[AaronWhitt82]

Engine Nut -

Thank You Soooooooo Much for the reply. Now I can get on with the tuning.
Everyone I was asking about it said it was 750 CFM, but I guess they were wrong.
The secondaries definately have too heavy of a spring in there and I need to put the lightest one in and work my way up and go from there to figure out what RPM's the secondaries will open at and which is the best setting.
Previous owner or whoever worked on the carb had it all screwed up.


Thanks again,
Aaron

[Engine Nut]

Engine Nut -

Thank You Soooooooo Much for the reply. Now I can get on with the tuning.
Everyone I was asking about it said it was 750 CFM, but I guess they were wrong.
The secondaries definately have too heavy of a spring in there and I need to put the lightest one in and work my way up and go from there to figure out what RPM's the secondaries will open at and which is the best setting.
Previous owner or whoever worked on the carb had it all screwed up.


Thanks again,
Aaron

We use a white secondary diaphragm spriing in our carburetors and a 2.5 power valve.