I'm installing the original cast iron intake back on my 383. I bought a valley gasket and some fiber gaskets that were listed as needed to go with it. I have two questions. First, are the fiber gaskets optional or necessary. My past experience w GMs makes me think they are optional? Also, the old valley pan that I pulled off, had what looked like fiberglass insulation sitting on top of the pan. Wondering if that's optional as well? One, more question. Do folks paint the top of the valley pan? Seems like it would rust otherwise.
383 Intake install
- Thread starter GMPolara
- Start date
Usually, you don't need to use the fiber gaskets. The rule of thumb for me is they are used with an aluminum manifold.
The insulation is optional too. They do make repops if you want one. It was mostly used to quiet down the lifter galley, although some will say it was for heat. Most people don't put them (or a new one) in.
I believe that the manifolds were painted along with the entire engine at the factory, so that meant anything under the manifold didn't get painted. Your call on what you want to do, but I've painted and left them unpainted too. They don't rust.
The insulation is optional too. They do make repops if you want one. It was mostly used to quiet down the lifter galley, although some will say it was for heat. Most people don't put them (or a new one) in.
I believe that the manifolds were painted along with the entire engine at the factory, so that meant anything under the manifold didn't get painted. Your call on what you want to do, but I've painted and left them unpainted too. They don't rust.
The fiberglass pack was termed "insulator", so many perceived it was for heat issues. But it could also be to dampen lifter valley noise. Pick the one you like. Later, somebody claimed it was there to keep the valley pan gasket from getting harmonics in it (i.e., drumming-type sounds), which could make it crack along the beads over time.
IF it got any paint, it was overspray from when they painted the end rail reinforcements on the front and back of the engine.
Enjoy!
CBODY67
IF it got any paint, it was overspray from when they painted the end rail reinforcements on the front and back of the engine.
Enjoy!
CBODY67
Just use the valley pan, skip the fiber gaskets.
I made up my own " insulator" with household insulation wrapped in tin foil.
I also blocked the heat crossover passages to reduce fuel perculation/ vapor lock and an electric choke was implimented.
I painted the exposed areas of the pan just for added attention to details.
Hope this helps.
I made up my own " insulator" with household insulation wrapped in tin foil.
I also blocked the heat crossover passages to reduce fuel perculation/ vapor lock and an electric choke was implimented.
I painted the exposed areas of the pan just for added attention to details.
Hope this helps.
Not a one size fits all question. Fiber gaskets are often used with aluminum manifolds as John said. However, if machine work required cutting of heads, block, manifold or all, then you may have to have them. Best practice is to drop the manifold on with NO gasket or bathtub, then look carefully at the boltholes and see how they line up. The threads should look ever so slightly high in relation to the manifold holes. Also, look at the end gaps carefully to ensure the angle of the mating surface is correct (so no air leaks). If all is correct, then you will be fine with bathtub only.....just put a dab of rtv in the corners of the china wall, and be careful not to over-torque the bolts. Probably no need to look so carefully if we are looking at all original parts to that engine, never machined. The valley pan (bathtub) can rust out, but it would be dang rare on a babied car no longer abused by daily use.
Good luck, Lefty71
Good luck, Lefty71
Just use the steel shim only intake gasket. Use a little RTV in the corners where the intake gasket meets cylinder head and engine block to prevent oil seepage or leaks. Clean all manifold bolts and chase the treads in the cylinder head. Oil the threads prior to install and torque to specs.
if you chase the threads on the intake bolt holes better to remove the valve covers and catch all the "debris" that comes out of those bolt holes. They are open to the insode of the engine buy the pushrods.
The valley pan won't rust it is coated. It will rust if the car is out in the weather without a hood like in a wrecking yard. We have all seen them rust through in that situation.
The valley pan won't rust it is coated. It will rust if the car is out in the weather without a hood like in a wrecking yard. We have all seen them rust through in that situation.
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1970FuryConv
Old Man with a Hat
On my 1970 Fury 440, factory 4bbl manifold, I did use the fiber gaskets. I wanted extra leak protection.
I did not paint the valley pan or use fiberglass. I used Permatex Ultra Gray RTV on the top of the block at the end bars.
I did not paint the valley pan or use fiberglass. I used Permatex Ultra Gray RTV on the top of the block at the end bars.
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ynst
New Member
The foil bag is a noise suppression device, not a heat insulator. Chrysler calls it a
"SILENCER PACKAGE, tappet chamber" and the part number is 1879 747
"SILENCER PACKAGE, tappet chamber" and the part number is 1879 747
I'm glad I put one in. I prefer a quite cruiser.
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