Manifold corrosion

[Eric Frarey]

New owner of 1967 Shelby GT350 1373. Looking for advice on how to treat light corrosion on cast iron exhaust manifolds after driving and storing for season. What is concourse correct method?  Read about slip plate product....Appreciate any assistance. Thanks!

[DennyD]

Congratulations on your new ride, it's a beauty!

[Eric Frarey]

Thanks

[GT350DAVE]

Hi Eric,
Contact Dave Mathews the 67 Registrar to get you into the Registry.  dmathews@prodigy.net
Dave

[JD]

Yes, congratulations!!

and get with Dave M...

[Royce Peterson]

For cars that don't get driven much the Calyx product works well.



If you drive your car a lot then you probably want to get the exhaust manifolds coated with something like Jet Hot which is a ceramic coating process. Regular powder coating will work for static display but is not heat resistant.
https://www.jet-hot.com/thermal-barrier

New owner of 1967 Shelby GT350 1373. Looking for advice on how to treat light corrosion on cast iron exhaust manifolds after driving and storing for season. What is concourse correct method?  Read about slip plate product....Appreciate any assistance. Thanks!

[Eric Frarey]

Thanks all

[greekz]

Beautiful car.  Congratulations and welcome!

[roddster]

  In concours, it has to be rust free.  Odd to me as when I did dealer prep for Chrysler in the early 1970's, I can tell you even then, the new cast iron manifolds were starting to turn on cars that were just days old.

  To remedy the situation on your car, you'll need to sand blast of the rust /corrosion, and coat it.  Calex has worked but I have found that 1) seems not to dry too well, 2) even then, a couple of years and the rust comes back due to moisture condesation under that coating.
  I have not tried a ceramic coating.  That might be more permanent.  And, I do not know if Jet Hot comes in a "cast iron" color.

[Eric Frarey]

Thank you

[J_Speegle]

Ceramic painting or coating will likely be something that holds up longer than paint and other coatings like the rub on ones But it means that you'll have to remove the manifolds to coat and heat/bake afterwards for a full coating.

Of course the cost of the coating is higher but IMHO well worth it.

Remember to resurface the manifolds while you have them off since originally no gaskets were used between the heads and manifolds originally

Good luck with your choice

[Royce Peterson]

The Jet Hot color I use is called "Platinum". It looks exactly like new cast iron. It does not resemble platinum in my opinion.

I have used the Calyx in the past and when I did it was on freshly bead blasted cast iron. My experience is that it needed to be re - applied after every drive. It was not something I was able to keep up with but if the car is only driven on and off a trailer it might work.

  In concours, it has to be rust free.  Odd to me as when I did dealer prep for Chrysler in the early 1970's, I can tell you even then, the new cast iron manifolds were starting to turn on cars that were just days old.

  To remedy the situation on your car, you'll need to sand blast of the rust /corrosion, and coat it.  Calex has worked but I have found that 1) seems not to dry too well, 2) even then, a couple of years and the rust comes back due to moisture condesation under that coating.
  I have not tried a ceramic coating.  That might be more permanent.  And, I do not know if Jet Hot comes in a "cast iron" color.

[Eric Frarey]

Thanks

[Special Ed]

We have manifolds metal stripped as they come out  of tank cleaned inside and outside then take a torch and start on one end heating up and take torch to the other end and u will see the moisture come out of the cast iron pores then while still warm coat with whatever coating u choose and coating will melt into manifold pores.  The key is to get all moisture out of porus cast iron first before coating.

[J_Speegle]

We have manifolds metal stripped as they come out  of tank cleaned inside and outside then take a torch and start on one end heating up and take torch to the other end and u will see the moisture come out of the cast iron pores then while still warm coat with whatever coating u choose and coating will melt into manifold pores.  The key is to get all moisture out of porus cast iron first before coating.

+1 Really important if painting or oiling a surface. Also opens the pores to accept the coating