Thread: off idle stumble

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it all seems good and i have cured it a bit by modifying the pump lever and i get a real heavy shot of fuel.
i am wondering if ign is the problem?

yeah the bushings are nice and tight no movement, the car even will pop and literaly stall if you punch it from idle. if you load it up againt the convertor and flutter the throttle before floring it it gets up and goes not great but at least it goes.

There seems to be more than a touch of confusion about manifold vacuum and ported vacuum.
I'll make a separate post pertaining to some tests I ran comparing manifold (or full time vacuum) to ported vacuum (also known as timed vacuum.)

Title will be, "About vacuum sources and timing."

further info on off idle stumble.
i think i finally solved it. i timed and played and changed dist springs etc but still had the funny bog off idle that woulf not occur at speed.
went back to the carb and started at sq 1 again. i found that the set screw on the secondary air valve flaps on the carb was kind of screwy it would tighten up but would not perfectly hold the set screw. so the secondary butterflys would open off the throttle and i have them set very agressively when i put the carb together and the air valves seemed ok but would open too fast for the engine and lean bog before catching up. stole another set scew from a old carb set the air valve again and all seems good. nice no bog fry the tires off the line from idle launch.
now to the next goal some kind of traction maybe a mini spool.

if ya mess with something long enough eventually you will figure it out