i had a 327 in my 57 that had a slight ping noise at
#7 cylinder it was about 12 years old at the time so
i kept running it it lasted another 5 years before #7
rod went thru the oil pan getting on the free way,
it made alot of noise and i kept going on the side of
the free way untill i made it to a off ramp the i found
a gas station then flat bed home. now i have a 350 4bolt
and spent 190 bucks for balancing,i really think $190
was worth it it revs real fast and runs real smooth.