Boat exhaust manifolds on a car engine?

I like those old Nicson boat exhaust manifolds but I was just wondering if you can you use them in a car. I think they will look killer on a (for example) Rocket Olds.

 

I have heard "rumors" of them cracking apart from the heat because on a boat they are water cooled HOWEVER, I know of a couple guys running them and TO DATE have had no issues.

 

ya man, I have a NOS set of weiand marine manifolds for my nailhead that I can't wait to use on a hot rod... I was going to install a set of marine manifolds on the sbc in my plymouth but sold the car before I had a chance ( plymouth wagon had a boat theme). Their was a car in rod and custom awhile back that had aluminum manifolds and they claimed they were holding up fine, but I want to ceramic coat mine on the inside for extra insurance.

 

What if you ran the hoses that would normally feed the heater to cool the manifolds?

 

are you talking about using the engine coolant to cool the exhaust manifolds . and then recuiculating the coolant back into the radiator? i don't think it would work..i'm sure it would overheat. on a boat the motor is cooled by a never ending source of cool water..the lake or river..then that water is run through the exhaust manifolds and then out the exhaust back into the lake

 

The water in the manifolds is "constant loss". Can't do it.
I was gonna put a pair on my Ford but the manifolds were too narrow to go outside the cowl and too long to put turn downs on.
I suppose the ends could have been cut of fand redrilled but never investigated further.
I do think if you could get it off they do look *****in.

 

I'm sure you are right.

 

These are actually pretty cool looking.

 

I don't know about the manifolds, but about 15 years ago I had a ratty old chopped 51 Chevy pickup with a junkyard Olds 455 and marine headers. They looked wicked scary on there, but holy **** was it ear-splitting at that higher level, even with the out-turned outlets. Cops didn't think too highly of it, either.

 

Those type of manifolds on boats are used to preheat the water before it goes into the motor, the water flows through a water pickup on the bottom of the boat to a water pump,then through the manifolds, then into the block, out the block and then dumped into the exhaust to help quiet the exhaust noise. Remember lake water is anywere from 33 degrees to 90+ degrees and a motor would run way to cool without the preheating.

 

These are for a 394 Rocket Olds. They will look great when they're used as a 'limefire style' header in a hoodless hotrod. And maybe the air current will prevent them from cracking up..

 

I would have them ceramic coated (on the inside to sheild the aluminum from heat).

 

Unfortunately I cannot use the manifolds shown in the picture as I have a 303. But I will keep my eyes open for a set for my motor.

 

Here is what they look like on a 54+/- Olds 324:

 

That's what I call a good looking motor!!

 

Thanks. It came out of a 19' flat bottom boat my father in law built in the 70's. He tweaked the motor with various hot parts he had at the time. That boat would run like a scalded dog all day long and into the night! It was a great ski boat. When he dismantled it, he saved the engine. It is now targeted for a 28 T coupe that I am going to start in a few months...

 

What am I missing here? What is the purpose of putting marine manifolds on a car?

 

I've got a decent collection of super cool marine "LOGS". Edelbrocks, and Nicsons.

The reason to run them??? They are cool/different/vintage/BAD ***.

Run "Dry"
As alot of guys have alluded to. They can be ran "dry" depending on which set you have......take that with a grain of salt. I've seen it go both ways. Ran dry, and cracked in 10 minutes, as well as ran dry and never had a problem.

Plumb for water, and make a secondary closed system.
You don't want to add them into your current closed system as it'll super heat your primary cooling system for the block. You can plug the "open" system ports on the end of the logs to close the logs down. This would entail TIG'ing them closed. Then drill and tap into the water jacket on that end to give the water a place to go. Go ahead and plumb that as the return to the radiator or cooling tank you have setup with your secondary system.


I won't be letting any cats out of the bag as I didn't go this route, but maybe one day I'll do it.

Picture a Nailhead with Marine exhaust turned with the outlets facing forward plumbed into a pair of turbochargers. Super clean install and twin turbos.

 

Wouldn't "block seal" work for filling the water jacket? Thus preventing cracks?

 

It wouldnt take much to make a set of knock off manifolds that look like marine use.

 

NO WAY MAN!...my friend used a nice set of aluminum marine exhaust manifolds on a small block chevy in his 40 ford truck - they MELTED!...yea, no lie!....i would NOT use them - hang them on the wall or on your dummy engine - just not on one that you want to run!....

 

Looks. It's all about the looks, man.