1970 383 Stock Exhaust Manifold Temperature ?

moparbeepbeep

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I treated my exhaust manifolds with Calyx....They are off the engine so I was able to get them coated as directed... I backed them in the oven @ 300 degrees for an hour... went to take one out and my gloves got the coating on them.....baked them for another hour @ 375 degrees and them them cool... coating still comes off to the touch.. the directions do not give info on how hot to get or how long... only coating them on the car and let the car get to operating temperature. So what do you gentlemen think that temp could get under normal conditions ??
As always... Thanks
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AR67GTX

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Far as I know that coating will always rub off to some extent. I did my 67 GTX manifolds with Calyx almost 20 years ago and it still rubs off on my hands when working around them. I don’t think heat affects it any unless they have changed the formulation.
 

dadsbee

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Did mine with VHT manifold in cast iron. Bake one was in front of the wood stove, 2nd in the oven as high as it would crank. Nothing ever came off or comes off on my hands to this day. Still haven't rusted 6 years later.
 

moparbeepbeep

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Did mine with VHT manifold in cast iron. Bake one was in front of the wood stove, 2nd in the oven as high as it would crank. Nothing ever came off or comes off on my hands to this day. Still haven't rusted 6 years later.
Thanks for your input.... I put in my BBQ grill and set to 700... will try that and see if dries then.
 

moparbeepbeep

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Far as I know that coating will always rub off to some extent. I did my 67 GTX manifolds with Calyx almost 20 years ago and it still rubs off on my hands when working around them. I don’t think heat affects it any unless they have changed the formulation.
Ok... I think that would be good info the manufacturer could give out when shopping for a product...
Thanks !
 

lewtot184

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cast manifolds can get over 700f when driving. the highest temps will be where all the runners converge. lowest temp will be at #1 (400+f). i've checked this several times on my cars with an infrared gun.
 

Matthew J

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Cars are probably tuned to run a little hotter today, but we design exhaust systems assuming normal operating skin temps are around 500 C (932 F). Temperature spikes under load of 800 C (1472 F) are common in gas engines. I've seen some over 850 C.
 
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