I just rebuild the Quadrajet on my truck and the idle and part throttle performance are great. I'm having a problem with WOT though. When I floor it and it gets up to around 4500 RPM it starts to surge and it becomes very difficult to accelerate any more, it's so bad that it's actually much quicker to shift and lower the RPMs. The cam in my engine should pull hard to 6500 RPM no problem. I have the spring on the secondary set at 3/4 of a turn and the choke pull off is about 1.5-2 seconds. This has been going on since I got the carb, rebuilding it didn't change anything, neither did switching from an auto trans to a manual.
This is the first time I've really gotten into carb tuning on a car (I'm awesome with motorcycle CV carbs) and I'm not really sure what is going on. Perhaps a lean condition?
