Holley Main Body Upgrade Question
Have you tried turning the mixture screws in a tad? How bout lowering the floats a little as well? What's your AFR at 30-40mph?
The mixture screws do not seem to make a difference really. If I do turn them in too far, then the engine runs bad and then shuts off.
I can't remember exactly the numbers off the top of my head, but I had leaned out the primary jet from 71 to 69 and two things happened: 1) my cruise A/F did get leaner than before (now it's somewhere in the mid to high 13's I think at about 40 mph - can't remember exactly and hard to record and drive), 2) when I step on it it goes leaner than I like (in the 15 to 16 range then goes back down).
Edelbrock Experiment:
I did try out an Edelbrock 650 AVS just for poops & giggles. The throttle response from a start was a amazing, but the cruise was a bit rich and the power was VERY lean (when you step on it from cruise, it would go between 17 and 18 on the A/F gauge with a stock Edelbrock calibration). I was also able to lean out the idle to an acceptable level too. I did try messing around with different metering rods and jets. I was able to improve the cruise, but not the power. I thought about giving it another shot, but I didn't want to waste any more money on it.
Back to the Holley:
Anyway... I kinda gave up on the Edelbrock and went back to my Holley because it was the most predictable. Also, even though it was rich the idle was smoother on the Holley. I just bet with the right carb parts and timing I can get it running in an acceptable range to get the best daily driver (yes, it's a daily driver) street power and fuel mileage.
