1970 440 Exhaust Manifold Heat Riser & Coating Question

[DMateya]

Hello,

I just got a pair of original 440 exhaust manifolds for my 1970 RR. It did include the heat riser assembly. What is everyone's opinion of that component? I am trying to restore my car to as original as possible. I see that they also sell heat riser rebuild kits as I am not sure if mine is in working order or not. I have read that these can become noisy and problematic. Any advice is appreciated.

70-74 383HP-400HP-440HP Exhaust Manifold Heat Riser Repair Kit with In


Also, has anyone restored original exhaust manifolds? I know that from the factory they were just left cast iron but today you can get ceramic or cerakote to preserve the manifolds and keep them from rusting in the long term. Has anyone here had their manifolds coated with something?

Thanks,
Drew

 

[Jerry Hall]

I restored the exhaust manifolds on my Superbird 25 years ago and coated with POR 15 cast blast coating. They cured with the heat of the engine when first cranked. I also replaced the heat riser with a kit so it works as designed. After 25 years there is only minor discoloration on the intake manifold, in the heat crossover area.

 

[Bird 426]

They are only noisy when they are worn out. I used cast iron header paint on mine. They have to be really cleaned of rust. Mine still look good after 3 years. Let the paint cure or follow their instructions. Rebuild the heat riser.

 

[DMateya]

Any other comments on the heat riser mechanism? I got the rebuild kit but want to see everyones thoughts on rebuilding the heat riser or just rigging it up to look functional. Since I am restoring my car I am not really going to be driving in the winter or super cold temperatures. I just like the original look.

 

[Jerry Hall]

You bought the rebuild kit, why not use it? My opinion is that the next owner may drive the car more and even in the cold. Most of us say we will never sell, but they change hands every day and none of us live on this earth forever. A functional heat riser is beneficial for more than just cold weather. It also allows the engine to come to operating temperature quickly for less engine wear. Just my 2 cents.

 

[Sam69sat]

Some people sweat Slip Plate graphite lubricant is a good coating.