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Join Date: Mar 1999
Location: Agawam, MA / Sarasota, FL
There were in fact 6223 forged, crosdrilled, and nitrided cranks. I have a special NOS two piece (broken) one in my garage. The 7115 piece was used in 68-69 L88's and 69 ZL1's and is the only GM 3.76" stroke crank that is counterweighted for the big 7/16" rods as those were the only 427's to have the big rods. L36, L68, L71, and L72 427's all had smaller 3/8" rods.
USAF Retired (1968-1988)
UTC Aerospace Systems, Space Systems International - Retired (1989-2014)