who has done the center rise manifold conversion on a 350? do you see results?

[FishAbility]

Originally Posted by Dirtguy

Actually, it's like replacing the stock ehaust on a truck with more efficient headers.

The log style pollutes each cylinder downstream slightly. The center rise, is more even on exhaust. So it should be better. GLM has a short runner in the manifold. Stock Merc just dumps into a big opening.

GD

yup. ive heard that they improve economy by 5% or better and give up to 15% more HP and Torque, now where these numbers came from who knows but this is what theyre claiming... we will soon see. they say theres a better exhaust sound as well... plus cooler more efficient running engine. cant beat it... i get them on wed and hope to have the boat out on the water by next weekend... ill let you know!

[skelly1]

If they make a big enough difference, go for the fresh water cooling before they rot too much.

[murderNmako]

Hey dude, I did the change on my old boat, afterwards it ran cooler and had more power, are you going to run a spacer? I chose to but I had a problem water backflow when backing down.. good luck with her.. ps go2marine hooks it up pretty good that is where I have got all of my exhaust parts from..