Vacuum Question
(1) Does all that I've done explain why the stumble went away ? -- (2) Should I put the vacuum tube back onto the ported side of the carb and be considering some changes to the carb instead ?
Not enough info to answer (1). It would be more guessing and speculation. Post #7 is as far as I'll go with that.
As far as (2), in general yes, but again not enough info. See post #5.
The following gives us the possiblility of 2 or 3 engine configurations.
I have a early (66) 383 Mopar, pretty much stock
and this suggests it may be none of the above.
Timing set at 15 and 36 degrees.
To know the curve we need the RPMs and at least a few in between points. If its the original distributor that came with the engine, the specs are in the shop manual - so that can be estimated. But most guys who street rod put something else in. So who knows.
The motor had a flutter under slight acceleration between 1500 and 2200 RPM, with the vacuum hose connected to the "Timed Vacuum" port on the passenger side of the carb. -- I moved it to the "Manifold Vacuum" port on the driver side of the carb, and readjusted the idle, downward. I also moved the accelerator pump bracket from the middle hole to the hole nearest to the carb body (increased the squirt), and the flutter went away.. -- I moved the pump bracket 1st - slight improvement -- then switched the vacuum hose - presto, problem gone.
Changed too many things to guess what effected what. Very light acceleration should be fueled by the "idle circuit" which includes the transfer port. Pump shot helps cover the delay when the throttle is moved quickly while on the "idle circuit".
No adjustments to the carb, other than a slight adjustment to the 2 idle mixture screws - very near to the edelbrock settings.
Who ya kidden? :poke: LOL
You adjusted the base idle mix.
"a slight adjustment to the 2 idle mixture screws"
Maybe did something with the thottle position
"and readjusted the idle, downward"
Changed the pump shot twice
"moved the accelerator pump bracket from the middle hole to the hole nearest to the carb body"
Timing is set at 15* at 900 RPM, vac disconnected.
Why is it idling at 900 rpm with a stock engine?
Runs fine, as is, up to 80+ MPH - tempted to leave it as is, but don't want to cause other problems
Can't tell whether you're interested in tuning, or just happy with it the way it is. If you're happy, enjoy. If you enjoy tuning, then keep working on it.
