Big Block Exhaust Manifold

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71RAT

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Deerfield NH
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Kirk
Truck Year
1983
Truck Model
K20 Scottsdale
Engine Size
461
I couldn't wait until I do the rebuild/restoration of my truck. Exhaust leaks were hellacious! The passenger side manifold has seen better days. If I remember correctly, isn't the passenger/right side manifold the same as cars and 2wd vehicles.
 

fast 99

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Have a machine shop grind/sand them flat.
Use high temp orange silicone, no gaskets. Will not leak.
 

71RAT

Full Access Member
Joined
Jan 11, 2019
Posts
109
Reaction score
80
Location
Deerfield NH
First Name
Kirk
Truck Year
1983
Truck Model
K20 Scottsdale
Engine Size
461
Have a machine shop grind/sand them flat.
Use high temp orange silicone, no gaskets. Will not leak.
So you've had success with no crappy gaskets?
I found one with the same casting # for $75.00 with shipping. #8 port doesn't have much material left just above the back bolt. That one already has been resurfaced atleast once.
Thanks
 

fast 99

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Location
Spokane, Washington
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Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
Yes, haven't used gaskets on 350 or 454 cast iron manifolds for decades. Have installed a bunch. I can guarantee if you use the gaskets that come in most sets it will leak. The manifolds expand and rip them apart.

Many later engines use a stainless gasket like a LS. Want to use those if they came OEM but still have to make sure the manifold is flat.
 
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