Oddfire

[RealFastV6]

Got a question...

On-Center blocks were designed to center the rod in in the cylinder for strength. I THOUGHT I understood that the REASON they weren't centered to begin with was that when Buick V6s were oddfire, the rod was centered, but when they went to split pin for evenfire it then pushed the rod off center.

If thats the case, then why/how would someone build an oddfire motor with an OnCenter(153) block? Wouldn't it screw up the rod center again?

Just wondering as I saw mentioned somewhere someone had an OnCenter Oddfire motor for sale.

 

[EightSecV6]

odd/even fire has no relation at all to on or off center, odd fire was switched in '78 I believe to even fire for idle quality and low RPM vibrations in production vehicles, odd fire is actually a stronger crank because it does not use a split pin on the rod journals but it does not operate as efficeintly. The off center refers to the position of the rod in relation to the pin, the off centers came first and the on centers were later and much stronger.



clear as mud, I know what I mean but difficult to write it!!!!