AndersonsSS01

alright so i have a 383 sbc in a 69 camaro with a 4 speed, its a pretty mild driver and i think the cam that is in it is a lunati voodoo 61003. Any way its got a holly 650 carb on it right now and it loads up really bad in the lower rpm's but once you get up around 2500 and above it still runs rich as hell but alot better. So i guess what my question is, is that to much carb for that engine or do you guys think it is just a matter of getting it tuned in better?

Italianjoe1

A 650 is perfect for a 383 unless you are revving it super high, sounds like the accelerator pump shot is too big/early, i'd start with the basic adjustments and make sure everything is good, then move to shot size profile.

mr.beachcomber

I'm guessing that you have a double pumper Holley on the engine as your complaint about performance under 2500 RPM is the same that I experienced with my 350 solid lifter LT-1 on the street with a super wide ratio T-10 and 3.35 rear end. Rather than swap out for a numerically higher rear end, I found that tuning the carb was the easier solution. (The carb was jetted for competition, not street driving from the factory.)

I dropped all the jet sizes two numbers from the factory offering, made sure that the pump shots started flowing as soon as the throttle blades start to open in both the primaries/secondaries, and learned to feather the throttle below 2500 RPM on the street while in 4th gear.

Hope this helps!

93 LT1 Vette

What model number on the carb, old and rebuilt or new?

A lot of variables when it comes to tuning and adjusting for street use. Double pumpers are designed for wide open use and suck on the street but can be tamed a little by proper jetting, idle circuit, float and pump shot adjustment. Timing and advance can also tame the double pumper alittle bit. How much timing are you running at idle and at full advance.