Fellas,
I read the pro's and con's of headers vs. manifolds, each has it's benefits and drawbacks.

I'm in process of installing a 509ci BBC with radical roller cam and 10:1 compression. With that said, I could use the cylinder scavenging benefits of a full 32" runner. Stainless Marine makes a (in my opinion) a bullet proof Gen. III manifold, riser and stainless tail pipe, however the 15" runner scares me. Is it worth spending a little extra $$ for CMI's 32" runner header? (and yes, I know the headers look kick a$$ and probably sound a little better)

My friend has the GEN III's on his Falcon, and they have worked flawlessly.

Oh yeah, the boat is a 1971 Donzi GT (looks like a Classic, but is beamier) and will utilize Arneson's extension box and #6 drive in salt water.

If you have the $$$$$ go with the CMI. Just got them on my boat. They do look KICK ASS !!!!!!!!

Looks aside, The KE Manifold/header is by far the best HEADER, (Full 32" runners) and is manifold TOUGH, (No leaks!) on the market. I have run my set on my HP500 for 4+ years in the Atlantic ocean and have no problems. Plus, I don't have the H2O reversion problem either with my KE's! The only down side is they are not the eye-candy that some people perfer, and they are alittle loud! I put Shotgun III's mufflers on them also, again, with no problems.
Hope this helps,
MD

I can't vouch for Stainless Marine, but I will say that CMI has been nothing but helpful in setting up my exhaust. Got the wrong tailpipes (my fault), no problem, had custom ones made in a week and 1/2 - a perfect fit. I couldn't measure from the outside of the boat for custom tailpipes (Formula with Silent thunder platform), so they helped me figure out dimensions from the inside. Tore a header gasket adjusting rockers, no problem, overnighted me a new pair. They've been great.

Just my experiance.

Scott

Tried both types on my naturally aspirated full roller, 10:1 compression, 588inch tall deck. The Gen III pulled 5 more HP above 5,000. The CMI's are prettier, but the Gen III's work, besides, Iam starting my 4th boating season, and they still look brand new.

Nate...

Do the rest of your Donzi brothers know what you are up to?? Good thing I'm putting a 'Hawk on mine. I'll need to just to keep up!!

Woodsy

CMI all the way. I bought a set with the "cool collars" and they perform flawlessly. Also I found out a trick that makes them last years longer in salt water apps. On the runner, remove the rear cap and replace them with an adapter and a 1/4 inch hose. Run the hose out of the hull just above the water line thus allowing them to drain automatically after each use. I also think the CMI's have a lifetime time warrenty. Otto

Pat at Active Thunder is putting CMI on my KE675's, I have them also on my Sonic, never have had a problem, 88 hours and no leaks.

Troutly, You can see your reflection in them, eye candy it is.

Troutly,
I'm just an "Enginerd" by trade/schooling, therefore I make most of buying decisions based on performance/reliability data, (Enginerd's curse!), just like @ work! It's funny, when I look @ KE's headers, I see a BEAUTIFUL example of ENGINEERING/DESIGN and reliability, but, hey thats' the curse I mentioned earlier.
I would like my next set(s)? of KE headers to be coated the Mercury Racing Blue, if he can do that? I wonder if KE will polish them, that would improve the "Eye Candy factor"? Hmmmm?
MD