Just picked up an 84 Z28, which has a 350ci out of a 72 K10 Pickup. It has a fair amount of hop-up parts, including Dart S/R Heads, custom grind cam, shorty headers, edelbrock rpm air-gap intake, edelbrock 750 carb, etc, but doesn't feel nearly as powerful as it should be. It's also freshly rebuilt, with a .030 bore. It sounds real mean idling, and at low rpms, but it just feels like a dog when you step on it.

It has only been together for a little while now, and the guy before me didn't mess around with the carb that much, in fact all he did was turn the air/fuel screws out 1/2 a turn to be "conservative". Obviously that was far too rich, so I had a buddy play around with it a little today, which made it a little bit better, but it still doesn't seem to have the guts I expected. I just went out to the car, to see what the screws are currently set at, and he has them only 1/2 a turn out from being all the way in.. And on the way home the exhaust would pop and crackle under deceleration, could those be lean pops?

Obviously a good place to start would be to check the spark plugs, but I don't have the time right now, I'll do it asap tomorrow, I'm just wondering what a good "starting point" for the air/fuel screws would be. And actually, a good starting point for the timing would be appreciated as well. Other ideas on what may be keeping it "slower" would be cool as well, it's been a while since I've been under the hood of a Camaro

 

air screws are only a small part of an edelbrock carb... Metering rod size pump spring color and jet size that is currently in the carb will go a long way in helping tune the carb better... knowing if it is running rich or lean at the present will also help... The smoke and nose test is a fast way to tell if you are lean or rich... When you step on it does it puff smoke or smell like there is unburned fuel comming out of the exhaust??? If so you are running rich... If your eyes are burning from the fumes at idle then you are running pig rich...

But to get you a starting point... get a vacuum gauge and hook it up to the no ported vacuum port... (drivers side lower vacuum port nect to the air bleeds)... disconnect and plug the ported vacuum fitting (on the passenger side next to the air bleed screws) set you idle to where it is comfortable for the motor to run without loading up... it will change as you adjust the carb but that is okay...

Slowly turn the air bleed screws out until you get the highest vacuum reading on the gauge... this should get it just about right with what you have in the carb now... If it is still running bad more info on the carb will be needed...

As far as timing settings go each motor is different... I have had great luck with 14 degrees of initial timing at idle... and 36 to 38 degree total timing... but as i said befor this works for some motors but not others...