4bbl running rich.

Gator said

I did not see where anyone mentioned this but I may have missed it but I would adjust my mixture screws following Edlebrock's procedure.. My 340 was running rich at one time and that is what I did... Worked out well for me..

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I agree, though he mentions blue puffs of smoke upon goosing the pedal..which could be too much pump shot. There a few positions on the pump arm of edelbrock/carter carbs that increases/decreases that. If this is occurring in neutral 'no load' I'd say that's where its originating from. Under load then the step ups.
While info is needed.. we dont need to know every last thing. CID vs cam size is important, compression sure.. but mostly if we are either dialing a timing curve or encountering a ping issue...otherwise it's mostly not helpful for a rich off idle issue or pump shot issue... but let's not chrystal ball too much... lol.. but basically I'm getting at that it's safe to assume a 413 sb is a 4" crank ...and they dont make any sub 8.8.1 pistons for them...though they could, but turbos and super chargers havent been mentioned... so in other words... we can cut out some lengthy once overs on everything in and around the engine.