L72 block

[68-427]

Someone is trying to sell me an L72 427 engine with block casting number 3916321. I need your expertise to tell me if this could be a true L72. If it is a correct number, I will look further into the other markings on the engine. What other block castings were used in 67-68 L72 engines?
Thanks for the help!!

[YENKO DEUCE REGISTRY]

I think that's corvette - but I have sometimer's disease

[Mr70]

EARLY assembled~(block used until Jan.1968)~Passenger & Corvettes used these blocks.It came in either 2 or 4 bolt main caps.
Are you looking for something dated for your vehicle?..if so
the casting date is located above the starter mount next to the freeze plug.

Before this block,the 1967 427's used #3904351 as a 2 bolt for the 427/385HP Passenger cars & Corvette 427's used the 2 & 4 bolt.
After your block,the later 1968 427's used #3935439 available as a 2 bolt-390HP & 4 bolt-425HP for Passenger applications.This block I think was used for the early assembled 1969 427 Passenger & Corvettes as well..

[68-427]

Would this block casting have been used in any of the 67-68 Yenko Camaros?
Thanks for any help.

[Mr70]

I don't know..I'm not up on the 67-68 Yenko timetable,but THINK they might have as well as used block #3869942 too.
Others here will know for sure.

[427king]

321 casting used June 67 thru mid jan 68 Earliest ive seen is F77[June 7 1967] and the latest ive seen is A188. Jan 18 1968. It is used on any 427 vehicle low or high horsepower,not just corvette. I dont think its feasable to have a 942 block in a 68 427 car,in fact its very unlikely as the 351 run lasted almost a year before the 321[latest date known is around June 66 on the 942. Its probably pushing[although possible] it to think a 351 block was in a 68 yenko too.

[68-427]

So, it sounds like it is likely that a 321 block would be correct for a 68 Yenko Camaro?? What other block castings would be poosible for 68?
Were Aluminum heads ever used on any Yenko 427 engines that were sold to the public?
Thanks again.