Why not use the "old" C4 with the "new" convertor? Which one has more miles? How many miles are on the Cleveland? Have you gone over it to check it's condition? Before you make up your mind, check some things, like the compression (wet and dry), the cam lift at the valves (pull the valve cover and measure with a dial indicator), timing chain slop (watch the rotor while rocking the engine back and forth at the balancer bolt), and most important, attach a vacuum gauge and observe what it does at idle and while driving. If the Cleveland is in good shape, you'll be much happier keeping it!
BTW, by "650 Holley 2 timer", I presume you mean double pumper, yes? What's it's list #?
Take care
~Chris
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Retired Moderator
MustangNet
My site:
JimPorterRacing
RACECAR spelled backwards is RACECAR
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