For 1971, the YC was not a HO engine.
Here is a chart for 1971:
What a couple of the guys were asking is that there is a partial VIN on the block down low by timing cover area, passenger side.
This would help determine what it came in.
It would look something like 21R123456
with the last digits of the car VIN
__________________
John Wallace - johnta1
Pontiac Power RULES !!!
www.wallaceracing.com
Winner of Top Class at Pontiac Nationals, 2004 Cordova
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KRE's MR-1 - 1st 5 second Pontiac block ever!
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