340 Chugging instead of Reving

1969GTS340 said

The engine has never ran right. It's a new built that has this issue since break in a couple weeks ago.

I read the manual and see where they call out the two coils you mentioned. It goes on to say that it is compatible with all OEM coils but recommend one if the above. I have an MSD 3 coil that I'll swap in to check off another variable.

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Don’t change the coil just yet. See if you can shorten up the curve a bunch and get more initial on it. Then if you don’t mind, tell us the exact carb and what you have in it for a tune up.

If it’s run like **** since the jump there may be more to it than bad ignition parts.

BTW, I have to ask because it matters. Did you actually degree the cam or just line up the dots?