1970 Fury HP Exhaust Manifolds Burn Valve Cover Paint

[66furys]

Gotta give em that, the chryslers were interesting at top end.....different than ford and chevy. They would roll. Early on I moved from plymouth to chevy. For drag racing, chrysler shifting was a challenge, and in 70's with the damn new process, all you did was replace shift forks.....not with borg or muncie, they would shift.

 

[3C's & a D?]

I'm going to throw a theory out here. You mentioned you have your crossovers blocked, could this have contributed to extra heat staying in the heads, closer to the exhaust ports rather than being distributed a little more evenly throughout the entire head?

Here's my '70 440, car originally was a 383-4 hence the manifolds and air cleaner. I was told it was rebuilt to HP specs, but who knows? It doesn't burn a drop of oil, and goes like a cut cat. First pics are from 2018, quick degrease, brush, scuff and spray job, no

primer as well. Not a ton, but a whole lot more that 30 miles on them since then, no burning. And I do give 'er hell on regular occasion. Second (dusty) pics from yesterday.

 

[68PK21 440.6bbl]

To the OP, or anyone else, enlarge the picture of the down view of the manifold and valve cover and notice the clearance gap from rear vs front, rear is more, middle & front are closer. Maybe just maybe in the engines lifetime the exhaust manifold was resurfaced as in this video?



.

 

[1970FuryConv]

To the OP, or anyone else, enlarge the picture of the down view of the manifold and valve cover and notice the clearance gap from rear vs front, rear is more, middle & front are closer. Maybe just maybe in the engines lifetime the exhaust manifold was resurfaced as in this video?



.

Really interesting video. I didn't know any of that about the new gen 3 hemis. Thanks. Dave's Auto Center Rocks!
I'm going to try Rustoleum 2000°F because a member on FBBO recommended against using the paint I used alone. I had 2 others tell me I need to use a primer and a clear.
If that doesn't work both exhaust manifolds are coming off. I checked them with a straight edge, but that doesn't eliminate the surface being cut on an angle. I have another set of HP manifolds I can try.

 

[livininharrow]

my 78 440 powered truck came from the factory with those exhaust manifold gaskets that protect the valve cover gasket. When I built my 70 Challenger six pack car I added one of those gaskets on the right side of that engine because the manifold is real close on the right bank but no so much on the left.
Here is a pic of my 78 engine. I still have the extra gasket if you wanna try it. It helps save the paint and gasket for quite a while. The gasket itself is a Mopar PN: 4095786

View attachment 660192

what kind of overdrive is that ?

 

[Sixpactogo]

what kind of overdrive is that ?

Gear Vendor

 

[3C's & a D?]

I'm going to try Rustoleum 2000°F because a member on FBBO recommended against using the paint I used alone. I had 2 others tell me I need to use a primer and a clear.

The factory didn't use primer or clearcoat. I think rustoleum has a high heat primer, but I've never seen a high heat clear.

 

[1970FuryConv]

The factory didn't use primer or clearcoat. I think rustoleum has a high heat primer, but I've never seen a high heat clear.

Realize that, but I don't have 1970 factory paint. Ad for Rust-oleum Clear
Rust-Oleum Corporation 260771 Rust-Oleum High Heat Paint | Summit Racing

 

[62maxx]

I have HP Exhaust Manifolds and I'm trying to switch to stock 1970 Valve Covers. I used Chrysler Race Hemi Orange to paint the valve covers. I did not use primer. Clearance on the right side from HP exhaust manifold 2806900 to the valve cover is tight. After 30 miles of driving, I had burnt orange. I have already tried Duplicolor Hemi Orange. It flakes badly, in addition to being runny. Does VHT SP120 stay orange long term in this high heat proximity to an HP Exhaust Manifold? Is there something better? Thanks. I really don't want to keep painting these valve covers. Problem is happening to a lesser degree on driver side.
2806900 HP Exhaust Manifold fits B-Body & C-Body Right side
View attachment 659822
Cannot take the heat
View attachment 659823
Close Proximity mount
View attachment 659824
Race Hemi now burnt orange
View attachment 659825
View attachment 659826

Last edited: Yesterday at 9:21 PM
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• Yesterday at 10:18 PM

Before putting on the passenger exh. manifold, did you check to see if the "bothersome" exhaust flapper valve is in the fully opened position or operating properly? (Mine was stuck and "frozen" open so I just left it that way) If not, maybe it's choking up the exhaust flow process causing extreme heat? Harbor Freight has those cheap thermal imaging scanners you can check your manifold for hot spots.

 

[1970FuryConv]

Before putting on the passenger exh. manifold, did you check to see if the "bothersome" exhaust flapper valve is in the fully opened position or operating properly? (Mine was stuck and "frozen" open so I just left it that way) If not, maybe it's choking up the exhaust flow process causing extreme heat? Harbor Freight has those cheap thermal imaging scanners you can check your manifold for hot spots.

That valve is removed and the rod holes plugged. 2.25 inch HP manifold outlet opens into new TTI 2.5 inch H-pipe exhaust. With valve removed, no restriction.