389 information
389 information 
Are you referring to a 3.8" stroke 4.03 bore (a 388) or 3.8 stroke 4.04 bore (390)? I would think it would be slightly more torque than a 383 and less worry of breaking the water jacket as with a 396. That is actually what I plan on doing in a few years once I need a rebuild.
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Mine is 3.75 x 4.060, which makes it 388.4 cid. The only reason I did it is because my 4-bolt converted, clearanced, zero-decked, and ported block needed a bore job and was already .030 over. You'll likely never see a difference in hp and torque from the extra 5 cid. I'd say about 7 ft-lb and 5 hp.
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On The Tree
Joined: Sep 2007
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From: HAYS, KANSAS
see i have to do it more than 30 cause my cam is flat and it put scratches in the cylinder walls and my friend told me to do a 389 but im just wondering if its worth doing it or will it **** up again.
