If GM goes " Tennies Up" ( old boat racing turm) what do Chevy guys use for engines? Can after market blocks be used as long as they are Iron?

The only ford I think I would run would be a cammer but only cuz thar purdy.

OK first a  confession here -- I have never owned nor will ever own a BBC if I have any say in the matter.  However as there are more BBC's in every boat, and in every wrecking yard than you can shake a stick at, why would you be worried about running out of them?  Most of you guys will never be building more than a 468 so what is the big dealio.
Not trying to hate, I just think the world we be done with internal combustion before they run out of Chevys.

Well sorry that no one is concerned.  Built my old circle boat out of all new parts back in the day and I believe that Comp Jet allowes a lot more than 496.  The question was, are after market iron blocks allowed? Chevy, Chrysler, even Ford. With the GM thing it only looks like costs will still be going up.

Oops my bad,  I didn't realize the topic of the thread was addressing engines for racing.  I should have noticed that from the way the first post read.  But the fact is that the bigger the motors go, the more sense it makes to build a Ford or dare I say Mopar?
Lakes Only has posted a few times the realities of how and why GM's are harder to make work when serious HP is the desired target.  No hate here, its just that the engineers never figured to build anythiing bigger than a 396 way back in like 1964/5.  You can only do some much to try and cheat geometry and physics.  Just adding bore and stroke ain't gonna cut it.
It is fun to watch the players when everybody gets out on the water though.  Comp Jet is some good racing for sure.