timeing question

moparsquid

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hi I'm running an old mopar performance dizzy that I believe is for the hemi ,it has no vacume advance and has a tac drive on it also. I have no problems starting up as it fires on first try always but when I pu it in gear and try to mash it seems to be boggy also it gets terrible gas mileage on the freeway and yes I'm running a set of 4-30 gears but I should get better mpg half a tank for less than 50 miles ,any ideas maybe a recurve ?
 

PurpleBeeper

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About the mileage....with 4.30 gears....50 miles for half a tank sounds about right (seriously). For the "bog", does it eventually "catch it's breath and run" if you keep your foot down? You may have a carburetor opening too quickly or not have enough accelerator pump "squirt". If it's just sort of "running like crap no matter what" when you floor it, then maybe it is your total timing is too high? or low? Check the timing at idle & revved up to say 3000 rpm or so to see what the maximum advance is. You don't "need" a vacuum advance and I have mine disconnected.
 

beanhead

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Why do you suspect the distributor? What is the timing set at now (initial/total/how soon all in)? Cam specs? You're getting let's assume an average of 5 mpg, with 4.30 gears and what kind of engine setup? We're gonna need more info...could very well be a carb issue.
 

Cranky

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Need to know a WHOLE lot more about your build in order to help.....
 

moparsquid

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i believe the timming was set initialy low as the fuel used to break in the motor was more or less 91 as for specs its the pic on my profile 2 600 carbs set up for the carb with x-ram eddy victor max headsi believe about 10.5 -1 cr. 550 lift solid and a 3000 stall converter carb starts right up and revs well in neutral but when i punch it it seems to bog a bit im thinking low timming and maybe no mech advance in the dizzy i really dont know what it ran on last but i believe it was a mp hemi tach drive oldie
 

moparsquid

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Is the mechanical advance, in the distributor, working right?
I'm not sure I really didn't test it out prior to installation but my suspicions are that its locked in and it is not working I have a friend here in my club who can recurve it
 

miller

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my suspicions are that its locked in and it is not working
That's always possible.

an old mopar performance dizzy
Or, if it's never been serviced, mechanical advance could be hanging up. That would sure toss in a bog.
Pull the cap, turn the rotor by hand CCW, and see what it does. Unless it's locked, it will turn a little, and go back on it's own.
 

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