472/500 exhaust manifolds

John Burchfield

John Burchfield

PCS Life Member
Does anyone know if exhaust manifolds on 500cid Cadillac engines are interchangeable with those on 472s? My '75 has a cracked manifold. I'm not at my barn where I can look, but the solution may be in the yard there-the '72 parts car I used for the body work. I know that searching for used manifolds can be frustrating-sometimes what you find is worse than what you have! If this doesn't work, I may consider some headers along w/ intake work and keep the exhaust quiet, a la Robert Shepard's Criterion! :thumbsup:
 
What is your 1972 parts car? I have been looking for the driver's door pull strap screw covers for my 1972 Fleetwood. I think any passenger car set would work.

I'm pretty sure the block for the 425, 472, and 500 were all the same but I don't know about the exhaust manifolds. MTS (Maximum Torque Specialties) in CA could probably tell you in a second. Www.500cid.com They would probably have a pile of the part you need. I need a 1972 right exhaust manifold for the Fleetwood 75 but I just haven't gotten around to calling them myself.
 
Kevin, my parts car is of the "larger" variety-a M-M Classic Duplex. Unfortunately it doesn't have pull straps like a regular passenger car. By the way, MTS also has a place in Ohio.
 
Kevin M. Parkinson said:
What is your 1972 parts car? I have been looking for the driver's door pull strap screw covers for my 1972 Fleetwood. I think any passenger car set would work.

I'm pretty sure the block for the 425, 472, and 500 were all the same but I don't know about the exhaust manifolds. MTS (Maximum Torque Specialties) in CA could probably tell you in a second. Www.500cid.com They would probably have a pile of the part you need. I need a 1972 right exhaust manifold for the Fleetwood 75 but I just haven't gotten around to calling them myself.
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put a picture in the want adds and I'll look for one the next time I'm up in the caddy store
 
Are there any benefit to putting headers on and not changing the stock exhaust? I have thought about putting headers on my 73, but I didn't know if it would be worth doing. I don't want my hearse to be any louder.
 
if you wrap the headers to cut down on the heat and use stock style mufflers and single tail pipe it won't be any louder them the stock system.
cons are they rust out. they won't stay tight and leak. the man bending up your y pipe needs to know what he is doing or they hang down and catch on everything. they are not cheap. you loose your heat riser.

pros are they hug the block and on the the caddy you can't see them from above. they will improve your top end preformace once the engine warms up you may see a little better gas milage. they woun't brake sitting in the garage over nght. you can go down to the locale parts store and buy a replacment set.

of course this is my list as I see it yours may be different
 
John ED Renstrom said:
if you wrap the headers to cut down on the heat and use stock style mufflers and single tail pipe it won't be any louder them the stock system.
cons are they rust out. they won't stay tight and leak. the man bending up your y pipe needs to know what he is doing or they hang down and catch on everything. they are not cheap. you loose your heat riser.

pros are they hug the block and on the the caddy you can't see them from above. they will improve your top end preformace once the engine warms up you may see a little better gas milage. they woun't brake sitting in the garage over nght. you can go down to the locale parts store and buy a replacment set.

of course this is my list as I see it yours may be different
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If you get ceramic coated headers they will not rust. Also use copper gaskets and they do not leak. About every oil change I tighten the bolts a little and never had a leak. I have done this since 2004 on my 49, and lots of miles.
 
yes I meant to say buy only the expensive ones and do regular maintenance and they will last. if like John I bought a car that all ready had them on it I would not change them unless I was forced to. but if I had a car that did not have them on it I would not put them on either.
 

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The headers I have on my 49 are shortys. Here is a pic right before this engine was installed. Before everyone says its not the correct engine, yes I know, but the engine that was in it when I bought it was a junk 350, so I just replaced it with a new one.
1949 S&S Knickerbocker combo 52.jpg
 
Headers or no headers?

I picked up all the parts for the life liner engine from the machine shop today and low and behold the exhaust manifolds are cracked. From a judging point of view what are the "rules" and while I am here what is the proper color to paint a 1975 caddy 500?
 
Thank you

Thanks for two things, first for the answer, second for setting the bar so high in our restoration, that picture looks awesome.
 
Dave Miner said:
I picked up all the parts for the life liner engine from the machine shop today and low and behold the exhaust manifolds are cracked. From a judging point of view what are the "rules"
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From a judging perspective, it would be considered a modification to the engine and would have a point deduction for originality.

and while I am here what is the proper color to paint a 1975 caddy 500?
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The correct blue engine paint is the dark blue. I suggest getting a quart of paint from Bill Hirsch in Newark N.J.. Cost is $35 quart plus shipping.

The lighter "corporate" blue was first used in 1977 Cadillacs...
 
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