aluminum exhaust logs

[icebox]

i want to run these on my 59 caddy 390 . they are off a boat and are double walled. do you think they will last . i am going to run them on a open front end. no hood or fenders.
icebox

 

[Dr Crankenstein]

Pure speculation, but I assume they're cast and meant to be water cooled. If that's the case, they'll probably crack in short order.

I'll bet donsrods can shed some light on the subject. Don?

 

[icebox]

they are cast . here is a pic of them .

 

[donsrods]

Dr. C is right, those are from a boat and they stay cool by water being pumped in and out between the two walls. If you run them without a constant supply of cool water they will not make it. You can't even run radiator water through them because they will superheat the water and make the car run hot.

I know they look cool, but there is a reason you never see aluminum manifolds on a car.

Don

 

[BigIrish]

So dumb question here - why would a boat or anything else run those? Why would it be necessary to cool the exhaust manifolds, as I thought you would want them hot (i.e. exhaust header wrap, etc).

 

[zzrodder]

I think it is to due with the fact that boat engines run under heavy load at steady rpms for extended periods, somewhat like driving up a never ending big hill. That can really cook things so cooling the exhaust manifolds will keep the exhaust valve temps down so they don't burn up. I expect it also helps keep the engine compartment temp down too.

 

[donsrods]

That is precisely it, you couldn't have a boat engine compartment getting heated up from high exhaust manifold temperatures, it would be dangerous. By running cooling water through them the temperature is kept to a mininum. You can actually put your hand on the exhaust manifolds of a running boat motor and they will only be warm to the touch.



Don

 

[440shorty]

Water

And boats have an endless supply of cool water to use, even with a heat exchanger, unlike a car.

440shorty

 

[Ricks Garage]

Come on, its a rat rod......put some aluminum turn outs on it and make sure your timing is advanced at a low RPM.....RUN THEM !!!!!

 

[sgtpontiac]

Pontiac used aluminum exhaust manifolds on

the Super duty motors.....GM Part # 9772521 and GM Part # 9772522

They worked well and were made of very heavy castings....Just a thought....

 

[Blue Eyed Devil]

Come on, its a rat rod......put some aluminum turn outs on it and make sure your timing is advanced at a low RPM.....RUN THEM !!!!!

Yeah... run them and destroy a neat piece of old speed equipment because it's a "rat rod".

 

[sgtpontiac]

BED.......I think you should change your handle....

Yeah... run them and destroy a neat piece of old speed equipment because it's a "rat rod".

To "The Devils Advocate"....LOL....just kidding man.....you're right....those things should be water cooled......any aluminum manifolds I've seen are some heavy duty stuff.....and even the pontiacs were known to crack....

 

[jmlcolorado]

Those are interesting.
I don't see wht a guy couldn't make those out of steel and weld on a turnout!
Heck, I like the look and might try that myself