mhansen

I have a bone stock 1971 with a Cleveland 2V with hesitation at highway speed. Just did a full teardown rebuild of the carb. Problem did not go away. Reset gap on points and again, no change. New plugs, wires, cap rotor and no change. It idles smooth. It starts easily both when hot or cold. Has lots of power at 1/2 throttle and wide open. Just hesitates or stammers slightly at a steady speed of 40 to 60 mph. Help is greatly appreciated!

THUMPIN455

How much total timing do you have when the vacuum advance is connected? What part of Mi do you live in? If you are in the U.P. you could stop by and we could figure out what it needs.

2+2GT

Have you had the distributor timing curves checked? I'm betting they are way off.

mhansen

Hooked up a timing light. A little throttle shows the vacuum advance is pulling it ahead fine. Unhooked vacuum advance and plugged it off. Idled it down and set timing at 6 degrees (spec in book). Road test and still have the stammer hesitation. Runs great wide open and idling, but that sight hesitation is still there at highway speed. Is it worth the time to change the condenser? One other thing, maybe I'll run it after dark with the hood up to look for any spark jump. Wires are new, but...

P Zero

At what RPM does the hesitation occur? And is it an actual hesitation, as in slight throttle application or is it at a constant throttle and it misses?

mhansen

1500 thru 3000 approx. Not really a miss or lack of a cylinder firing. It's not that obvious. More like you are driving in a fairly strong headwind, and then the wind is gone, and then it's back, and then it's gone. It's almost cycilic (has a rhythm or reocurring cycle to it). No, it's not the AC kicking on and off (belt is off), but it sure feels like that! But the cycle is faster. Every couple seconds. Has me dumbfounded.

mhansen

Forgot to answer your second part. It's at constant throttle. If you go to half throttle to pick up speed, it is smooth and has good power.

2+2GT

Advance doesn't work that way. The exact amount of advance at a given vacuum is critical.

However, since it runs at WOT, it's probably not bad condenser or points, it would be worse then than cruising.

mhansen

Problem solved using this diagram. http://www.mustangbarn.com/images/va...and%20dvcv.gif

Former owner (always blame the one up river) had two vacuum lines switched around on the temperature distributor vacuum control. Thanks everyone though for pointing in the "distributor timing" direction. I wouldn't have found it otherwise.

jonward786

Edit: oops just saw u fixed problem.