IDK, weve never done it BUT I think when you look at PRW , ati, tci, atp etc for aftermarket flex plates they do NOT have listing for gen v/6 cast crank vs forged crank for a flexplate for a hotrod/street car, just the same part #, maybe they split the difference, IDK, Smitty

ATI most certainly does show 2 different ones. Dont know about the others.

Im not sure Bill, ATI shows THIS on their listing
:NOTE 2: Cast crank only - 41.95 oz. in.
NOTE 3 Forged crank only - 42.54 oz. in.
and has a different column then seperate listing for EACH, BUT goes on to assign them the SAME part # : 915541
https://www.atiracing.com/products/f.../flexplate.htm

Interesting. My print catalog shows 915541 is for internal balance. 915552 (forged) and 915553 (cast) are for external balance. I dont see the 552 and 553 in your link.

So, I just downloaded the 2023 catalog and it looks like they have done away with the external balance ones for the Gen 5-6 ??? All they show is the 541 which is internal balance.

I have to call them today and order some damper parts. Ill ask them and see what they say.

Yeah to muddy things up worse, I just looked at ATI again and even though they have those balancing notes mentioning cast crank /forged crank and and both have same part number, it also shows it as INTERNAL balanced like the part # out of your catalog so it way AFU!

Ok, I talked to ATI a few minutes ago and they did away with the flex plates because there was no demand for them. I guess if you think about it any marine application would be a manual trans type flywheel anyway. Most performance and race Big Blocks that I do are pretty much internal balance so there is no need there either. And if you are balancing the assembly anyway I guess it does not really matter which one you use as long as you make note of it for future replacement.