SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: Sicaz66 on May 13, 2013, 07:52:54 AM

Title: Cmi header install
Post by: Sicaz66 on May 13, 2013, 07:52:54 AM
Getting ready to install my cmi headers. Removing a set of Hardin logs on my 454. A little confused on water hose routing? Old setup had raw lake water into logs,then warm water into engine then out to snails. New headers only have hose in then out exhaust? So do I run raw lake water into engine then out the headers? There are plugs on top of headers,not sure what these are for?
Title: Re: Cmi header install
Post by: Sicaz66 on July 08, 2013, 07:33:56 PM
I guess nobody has these headers? ???
Title: Re: Cmi header install
Post by: Horizonjet on July 08, 2013, 08:40:20 PM
If its like others headers lake water in waterpump, t stat housing one goes to t valve then to headeds, other side goes to gate valve to control pressure for header water then dumps out back but to be sure we need pics, lots of them :))

sent from my mobile wireless thingy

Title: Re: Cmi header install
Post by: Sicaz66 on July 10, 2013, 09:14:21 AM
If its like others headers lake water in waterpump, t stat housing one goes to t valve then to headeds, other side goes to gate valve to control pressure for header water then dumps out back but to be sure we need pics, lots of them :))

sent from my mobile wireless thingy

I dont have a waterpump,this is for a jet boat.there is no t valve,they are water jacketed headers,No idea what you just said??
Here what I'm thinking. Lake water tees into water pump holes in block,then out t-stat housing block out to headers?
Title: Re: Cmi header install
Post by: mash on it on July 10, 2013, 09:50:01 AM
I dont have a waterpump,this is for a jet boat.there is no t valve,they are water jacketed headers,No idea what you just said??
Here what I'm thinking. Lake water tees into water pump holes in block,then out t-stat housing block out to headers?

Horizon jet was thinking water injected headers.
The water jacketed headers I've plumbed have been on a 460/king cobra set-up.
Jet to water pump plates, then out t-stat housing, R&L to headers.
The plugs on top of the headers are/were for the 'overflow' for a merc/waterpump/t-stat setup.
What does CMI recommend?

Dan'l
Title: Re: Cmi header install
Post by: Sicaz66 on July 10, 2013, 01:28:31 PM
Horizon jet was thinking water injected headers.
The water jacketed headers I've plumbed have been on a 460/king cobra set-up.
Jet to water pump plates, then out t-stat housing, R&L to headers.
The plugs on top of the headers are/were for the 'overflow' for a merc/waterpump/t-stat setup.
What does CMI recommend?

Dan'l
Exactly what I was thinking.wasnt sure about plug on top of headers.( now I know). Only concern is now no warm water to engine?

Title: Re: Cmi header install
Post by: mash on it on July 10, 2013, 02:50:37 PM
Exactly what I was thinking.wasnt sure about plug on top of headers.( now I know). Only concern is now no warm water to engine?

All the squirt boats with headers are that way. Or add a heat exchanger, and keep it at 160 all day, but cooler water temps make more HP, too

Dan'l
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