From a performance standpoint I would be suprised if any manifold can compete with the KE header, all aluminum. I may be partial though as I run them. I also had the misfortune of disinegrating a seawater impeller on one engine. I felt the boat jerk when it went. Not knowing what it was I turned and headed about 5miles back to the marina. I run closed cooling and was watching my engine temp close and could see something was amiss but not out of hand. As long as I kept on plane plenty of water flowed through the system (even with no impeller) to keep anything from melting down. I did feel quite fortuanate though.....

BT

Okay, so can you prove that riding in a Cig is "the nautical equivalent of Viagra"? :D On second thought I think that question is better left alone. :crazy:

What kind of centers are required for the SM Gen III exhaust system?

34" or more on a tall deck configuration with merlin heads.. :(

On a short deck I would guess around 33 or so...

Buddy of mine is Running tall deck 588's with the Gill BIG GUN manifolds. 35" centerline's with no more than a 1/2 if that between the manifolds.


Jon

What kind of manifold was it that you "melted"? The Gil's were very prone to having problems when overheating and I don't recommend them... Gil says they've cured it but I don't see them on boats anymore.

I've owned headers and manofolds over the years and had both overheat at one point or another and neither one of them ever had damage.. On the flip side I know others who "blued" their headers and they developed cracks in the primary tubes and cracks in the welds near the exhaust ports.

Back when I was working at the marina, I saw a failure rate between aluminum manifolds and stainless steel tubular headers which was at least 5 to 1, no sugar coating... Not trying to bash them, I own them, but those are the facts that I experienced and it hasn't changed much since I got out of the field.

Bottom line....if you overheat bad enough it's going to cause damage no matter what exhaust system you have. :hitfan:

If I had 35" centers I'd be running the SM GenIII's....please don't rub salt in an open wound!!! :D:grinser010:

Distance Between Centers...
 

OK, I was all excited about going with DANA Fow Torque Manifolds until I called today to confirm they were direct replacements for my stock manifolds. They told me that the Min distance between centers is 34.5".... OUCH, my engines are 34"... I tried measuring at many locations and always came up with the same distance ( I did try one measurement on a diagnal and I had 36", just need to pry one engine over @ 3" at the front...:party-smiley-004:) Oh well, I guess it is back to the ugly Stainless Marine Gen IIs (if they will fit).

I have been looking to replace my Revolution Marine aluminum exhaust with either the Gil wet offshore or the Dana. I notice that the Gil, as well as other high end exhaust use multiple water inlets (manifold), whereas the Dana, Revolution, Imco, Stock, etc. only have one inlet on the bottom. Seems like the multi inlet would be better? Also, I know that the stock exhaust drains completely when you take off the single bottom hose, but I can't tell if other single inlet manifolds like the Revolutions drain completely.

Also, looks like the Gils have some of the longest tailpipes - the water and exhaust mix way back from the riser section. Should help better with reversion than some other brands? Can anyone comment?

The revolution are a good product, have installed them on 3 boats, oldest set are 6 years, still looking good and moderate performance improvement over stock on a 500hp bbc. You cant beat the price.