What is the difference between a 500,525efi mercury block and a 575sc block. Does the 575 have that many better parts for a super charger?

Thanks

Blocks are the same.
525 and 575 have H-beam forged rods.
575 has dished pistons.
500 and 525 have flattops.

I thought the 525 was a 502 and the 575 was a 540. I haven't done any research, so it's possible that I'm way off on this.

The 575 SCI is a 502 block

The old carbureted 575 was a 540

Thanks. Hi Biggus. Long time no see. I still remember meeting you at Monty's last February.

you gonna use that in F-1,or was that on the front seat of that caddy to,just kiddin!!!