I spoke with bobby at vsr regarding my cracked gtm manifolds and he recommended shipping them down to his shop to have them welded and cryo-treating the manifolds. The cost would be $100 per set.

That's a good deal. Might have to hit him up on that.

I'm no metallurgist but I don't know if cryo-treating is what you want. As I understand it cryo-treating increases strength and hardness of the material. Harder material has a tendency to be more brittle. In a location that is going to constantly heat cycles, I'm not sure you want to have it be harder. I know we are very selective where we use high strength materials offshore.

I used to work with an engineer that knows a bunch about steel make up and thermal expansion. I'm going to try and get in touch with him and see if I can provide you with any additional information.

Dunno, just seems like a losing battle.

Fix it one place, it will break another. Since the area of breakage is not isolated to one spot, you cannot guarantee that it just won't keep cracking on you.

That being said, who knows when/if the crack would be catastrophic. All I know is I wouldn't want to worry about it.

Do not lose hope cosmo, you do not want to get a GTR, I heard they instantly turn you into an "old guy"....be young with us, we have tequila!

Still researching on technique's on how to weld cast iron and came across this:

Stick Electrodes - Welding Cast Iron

Also found this very informative video on welding cast:

http://www.youtube.com/watch?v=Yopcz-IYDyQ

But do consider that people (like Cosmo) cryo-treat their blocks, pistons, rods, etc, and all of those endure tons of heat cycling.

GTM manifolds are cast iron, non of the parts you listed are made of cast iron. We need a metallurgist to chime in, lol!

So is a coating on the manifolds going to make it more or less likely to crack?

Beat me to the punch. Cast iron is a whole different animal compared to the steel used in the engine itself

I think next week I'm going to call a few company's that make cast manifold's here in America to get educated...

The video is the same way I would weld it, only with Tig. I would use preheat, and slow cooling too. He is using Ni-rod 99. I would use Ni-rod 55. ;)

If you can find out what type of cast iron is used. That will help alot in chosing on how the repair it. ;)

Would love to but gtm is no way going to admit their manifolds are garbage and help in any way to fix the crap they made... Rusty what are your thoughts on the cryo treatment. The way I see it I don't see how it would hurt anything..

I don't think coating the manifold will stop the crack

I like the idea in that video I posted of the guy drilling holes in both ends to stop the crack from going further and welding the middle. Maybe I should just send them to rusty and then to vsr for the cryo treatment.. Either way we need to figure this thing out because there be more to come...