stainless marine manifolds vs. tube type(cmi,stelligs)
 

1000hp and over......pros and cons

In na applications they don't have the runner length to create the scavenging affect. Blown they are probably fine. I just bought a couple sets of the KE cast headers to try out this year. They are advertised at a 32" true runner length header.

Dave

Stainless double wall tubular exhaust headers are prone to leak on the inside tube where the flange bolts to the head. When this happens no warning buzzers sound, there is no instrument on your panel advising you of the leak. So there you go fast as hell in your fast boat pumping water into your engine through the exhaust port.
Engines hate this. Especially Supercharged engines. When you are done screaming, you can now begin to spend a lot of money in parts, machine work and labor. Not to mention there goes the already short summer.
As you can probably tell I am not a fan of this popular type of marine exhaust.

SO MANIFOLDS THEN?

yes

Consider the KE header/manifolds as a good comprimise. I purchsed mine at 2k/set which is cheaper than SM and will rival tube headers in perfomance, or so they say. I will find out in the spring for sure. One of the deciding factors for my KE purchase was what Cig just said, leaks scare me.

Here is a thread we had going a while back in the TA section.

http://www.offshoreonly.com/forums/s...ickert+headers

Dave

stainless is painless bro

On Supercharged low rpm motors tubes are for looks and yes I have them :rolleyes: On the up side plug access is better.

To quote one of our old adds aluminum melts at approximately 925 F we "heat treat" all of our headers at 1925 F with a melt temp above 4000 F , now add 200 degree saltwater and egt's approaching 4000 F. What is the value of the engine?

i think your temps maybe off:eek: