Hello! I have a Holley 4160 600 CFM 4bbl carb on my 292. Out of the box it has the following: Primary side is 65. Secondary side is a jet plate with equivalent jet size of 69. The power valve is 6.5 with a 30 cc acceleration pump and an orange cam. Secondary diaphragm spring is black. That being said, I'd like to hear of what fellow inliners have experienced in tuning this carb and what size components used. I do have Holley manuals, etc.. I just never attempted messing around with this carb. I've heard of changing the accelerator pump to 50CC and changing diaphragm spring to the purple spring. Am I on the right track? I understand "its different for everyone", keep in mind other than headers, offy intake, I don't think much has been done as far as "performance upgrades". Looking at changing to a 260H cam, and possible head work in the future. As always, thanks in advance for all your help.

Diaphragm springs, just have to try diffent ones.

Best best is to get a wide band O2 reader that can record.
That will take all the guess work on the jetting, accelerater pump settings etc.
I do not think you need to switch to a 50 cc squirter.

I personally got better throttle response w/a double pump on my 250.

MBHD

Thanks, I'll get a spring kit and a quick change kit with it and just try them out. Appreciate the reply.

-Ted