I currently have a mild 302 windsor that runs the following configuration.
30 thou over bore
Edelbrock Performer RPM manifold
Cam is TRW TP205 (intake lift .472 duration 290) (exhaust .406 lift & 300 duration)
Holley 600 or 650 CFM carby
I have couple of issues
Not sure what CFM the carby is. As some highly intelligent individual in the past has filed off the model number on the choke tower
The size comes from talking to AFD and using the numbers from the primary and secondary butterflies as a guide to CFM size.
I am getting about 20lt per 100 km which I feel is probably a bit high. I was speaking to my uncle who over the years has owned a wide and weird collection of vehicles, he too feels it is high.
I have a vacuum whistle that is coming from the carby once it is heated up.
Therefore with these to issues in mind I guess I have 2 options.
A carby rebuild. Hopefully to find out more info as to the carby size, jet size and accelerator pump size. Fix the whistle (gaskets) and perhaps armed with current jet size and accelerator pump size if these are wrong put the correct ones in and possibly improve fuel economy not that I ever expect it to great.
Or a new carby if so what are peoples recommendations I have looked at Holleys website and it recommends a carby between 570 and 650 CFM. They have various model Street Avernger, Brawler, Classic, Quickfuel and Slayer. I went through them all and are suitably confused
as to what CFM or type to use. So if people some experience with any of the above your thoughts would be appreciated.