carb adjustments

[Paul]

my 77 T/A has a pontiac 455 bored 30 over with #13 factory heads, cam is a Comps XE284H, the carb is a quadrajet #17057266, I rebuilt it using Cliffs book recipe #3, lower end of all the settings, accelerator pump holes are .028 .060 idle down channel, .093 idle mixture screw holes,  air bleeds are all .070, secondary air bleed is .036, 74 primary jets and 44 primary rods, .090 bypass air holes. I havnt driven the car yet, im still tuning the carb at idle. The engine idles rough with around 7 inches of vacume, I cant kill the engine by turning in the idle mixture screws, but I havnt done the tip in proceedure yet. Any suggestions with adjustments to this carb befor I get to involved? When I disconect a small vacume line the idle comes up just a little.
Thanks,

Paul

[Cliff Ruggles]

I'd drop back to 72 or 73 main jets, and use our .044" rods with them. 

Did you use one of our kits for the rebuild?

7" vacuum is pretty low, even for that cam in a 455 engine.  Where is the initial timing set at and what rpm are you seeing 7" vacuum at?....Cliff

[Paul]

Cliff,

The 44 rods and 74 jets I got from you with a rebuild kit. I was able to get the vacumm up to 8/9 at 13 degrees initial timing at 800 RPM.

Paul

[Cliff Ruggles]

I'd like to see 10" or more vacuum at 750-800rpm's.  Might need to tighten up the mechanical advance curve just a bit, and add more timing at idle to help out some.....Cliff