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Sluggish off the line! HELP!

5283 Views 7 Replies 5 Participants Last post by  itsa65
ok, I have a 1968 Rebuilt 289ci with 302 heads, an edelbrock performer 289 intake with an edelbrock 600cfm 4brl carb, stock dizzy with new insides (still points). I changed my plugs which were really fouled, set my spark wires accord to chilton (two were in the wrong order). Im sitting at 15in of vacuum steady, carb vacuum tuned to highest vacuum possible. Im sitting at 8BTDC on my timing(max I can go before I get ping). it idles and starts up A LOT better with the new plugs and correct spark pattern, but from a dead stop, if I gas it hard it bogs down for about 5-8 seconds then picks up, its really bothering me because when I had the stock 2brl on there I NEVER had that problem, someone please point me in the right direction.

Thank you
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I had the motor and trans rebuilt in 04, stock cam, rear axle is 3.00, the guys that rebuilt it asked if I wanted 289 or 302, I asked for 289, I did have a vacuum leak and pulled the manifold off to fix it and pulled my vavle cover while at it and discovered 302 heads, so I havent looked at the crank yet but assuming its 289 with 302 heads, Ive found a couple other people thats happened to, some say they breathe better, not sure what up with that. while the manifold was off I took the carb apart and checked floats, needles and cleaned it all out. I put the manifold back on yesterday morning, used "the right stuff" gasket maker in the valleys, started it that night and checked vacuum still steady at 15in, I sprayed carb cleaner everywhere trying to find a leak and no change at all in idle. my dizzy is the original (new insides, had a shop adjust points gap) dual advance, retard is plugged (before I got it) and the advance is on the carb where there is no vacuum at idle. how do I know if my advance is busted? if I pull the line off while running and suck on it the motor picks up.
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An older guy from work that used build them back in the day (real older guy) siad I should set my idle at 950-1000 and it should be about 550 in gear, that seems a little high to me but Im no expert. chilton says 550 curb idle but not sure exactly what curb idle means. and I have been considering changing the whole ignition system, just waiting on some funds

thanks for the help guys I appreciate it!
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