With all of the RA V stuff I have done over the years I have learned a lot about Pontiac Engineering projects.The interesting things about this engine lead me to believe George had a big hand in this at his place Leader Automotive.Tom Nell spent a lot of time there and there was a part of the shop most people were not allowed in.The block has a EUN number and then went to special machining to get the dist hole made to the RA V-455 SD size.Also the 4.21 stroke 3in main factory crank was one of im told of a handful made.In the last 25 years of doing this stuff I have only owned one.I have a 303 std deck V engine in my car now built as a 428.I have learned to never say never when it came to engineering stuff.I would love to have the short block.Tom

very true on the engineering stuff. back then they could do as they pleased.

Listed on eBay.. https://www.ebay.com/itm/1970-Pontia...53.m1438.l2649




228870N107497

1970 Trans Am vintage SCCA race car
 

Has anybody noticed the "2605" block stamping on back?
As opposed to "2506"?

I just figured George could have stamped anything he wanted on it in engineering?I asked my machine shop about making my 303 engineering block into the large dist hole and he said he would not want to tackle it as it would need to be precise as the the dist gear fits into a hole at the bottom.A job for the factory machine shop.Tom