We'll I've been tickering w/carbs again. I have a 770 and 870 Avenger. The 770 Avenger runs good, but lacks the top-end that the 870 has. The 870 runs good from top to bottom, except I get a little popping around 5000-5500 that I couldn't tune-out, then it would clear out and pull much further than the 770.
In frustration, I put the 770 back-on to make sure I didn't develope some sort of ignition problem (the popping). Before I bolted on the 770 I threw some 84's in the back instead of the factory 75's just for kicks.
Guess what? I have a different car now! Pulls like a SOB all the way to the top. What is interesting is that I tried 82's as recommended by a few of you guys (Mr. 4-Speed and AK69), but she still feel on her face up top. Turns out this carb is so lean for my application that 82 and down the car wouldnt pull! That jump from 82 to 84 made a HUGE difference. I hope I didn't do any damage (running lean). They say these carbs are close outta the box but geeze, almost 10 jet size increase?
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