I Just Did A Google Search for Mark 55...
Quote:
Originally Posted by
194265
My answer was for Mark 55's not Mark 55H's.
I know that some Mark 50's were sand cast, but I never knew there was and never saw a Mark 55 that had a sand cast block.
When we legalized the Mark 55 blocks to run on Mark 55-H's, no one ever talked about sand cast blocks. We went back to 860000 serial numbers but the best 55 blocks were black with the serial number 89 something. They came off Mark 55 E and were high compression, but still within the 55-H specs.
I would have loved to have been allowed to run a Mark 40 block with the big carbs....in APBA D Stock.