Seems to be a hot topic lately and while I don't currently have CMI headers on my boat will most likely have them on my next.With everything I have heard about them they will not be there long.There seemed to be different opinions on if you could use Stainless Marine exhaust on the 525s so I spoke with Jerry at Stainless today.Yes you can but you have to re-drill and tap the heads as they are not GM heads the bolt pattern is different.Stainless Marine has a jig to do this and they will lend it out (with a deposit) to anyone who buys there product.There are a couple of other minor modifications like moving the water tank but the also offer the bracket for that.

I assuming that this will work with the GEN III manifolds also?
Sounds like a good solution, especially if you can use the GEN III manifolds.
Dean

Once you drill the heads its a standard GM pattern you can use anything.

Good idea, however I can't imagine drilling a non staggered twin set up with the engines mounted, hard enough just getting the exhaust off.

Still no replacement for the sound of a true header

the benefit to stainless marine is that they last a long time and don,t leak like the cmi's.
i think i would rather loose a few pony's to stay reliable and not blow my motor up and it cost lot's of $$$ to fix

mike

if you have a blower and gen III's you don't lose anything hp wise.

I agree, STAINLESS MARINE IS THE WAY TO GO !!!!!

Even on N/A engines . THEY LAST FOR EVER !!!

What about making a half inch adapter plate to adapt the bolt pattern?
The Big tubes we use have those to allow for bolt access, they should be available or fairly easy to make

Stainless Marine are gonna be my chioce!

HOW ABOUT JUST MAKING THE STAINLESS MARINE STUFF FIT;;;JUST LIKE STOCK