Carburetor Question (To Jet or to Go Up In CFM)

[KyleSeal]

What I need to know: do I need to rejet my Edelbrock? I have a 454 BBC with a larger cam and Edelbrock Performer RPM. My problems all started with the Holley no longer cooperating, backfiring through the carb, bucking at low RPMs, and dying at idle sometimes. So I moved down to a 600 CFM 1405 Eddy, and it actually starts. But I have to keep it at 2 grand to keep it running. Unlike the Holley, which would barley run at all.

So do I need to put bigger jets in it? I assume its stock. We've messed with the idle screws and mixture screws some but not much difference.

Or should I move to a 650 CFM? I know whatever I get I will also buy the tuning kit for it.

Originally I had a 750 Double Pumper with mechanical secondaries and it flooded the engine like crazy. My spark plugs were done in nearly a month.

and yes I know I'll lose top end power with the smaller sized carb. But honestly all I need is a good sounding truck. After all 1 ton's were not known for being fast. Just scaring ricers.

Thanks in advance, also if theres anywhere else I should check for problems please let me know. I'm learning.