351 Cleveland Tuning Issues

Hey all,

So I've got a 1970 Mustang with a 351C 2V in it. It blew out the Pertronix Electronic pickups after 3 years of use, so I installed a new Summit Racing HEI dizzy in its place and now I can't get the thing properly tuned! I've got the timing gun hooked up and originally set the timing without any vacuum hooked up to about 6 degrees (I read 4 was the factory setting, that could be wrong).

Then I hook up the manifold vacuum and it jumps all the way up to about 24 at idle with the total advance stopping at about 34 at 3000RPM. It almost sounds good but from around 1200-1600 RPM the engine shakes a lot indicating the timing is not advancing correctly.

Can anybody give me some tips on how to properly tune a carbed motor? I clearly cannot figure it out on my own.

It's got an Edelbrock 600CFM carb on it (1405 is the part # I think).

Here's the link to the dizzy I got:
http://www.summitracing.com/parts/SUM-850025/

Thanks for any input you can give!


Tim
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Just to be clear, you ran the car for 3 years with no issues and that included the Edelbrock carb?
Can you take the distributor cap off and manually move the advance mechanism and check for binding or less than smooth operation? I assume you are using full manifold vacuum and not ported?
Is there a manual that came with the distributor? On my 4V cleveland I run more initial advance (12 degrees or so) but have about the same total advance as you have and it runs fine. The 4V clevelands like a lot of advance.