Valve seat issues

[Bobby DiDomenico]

Thanks guys. These cars all have serious drivability issues with todays gasoline, especially the ethanol summer blends we are forced to purchase here.

Tom, I'm afraid that cutting the seats again and removing more material is going to make it worse. The fact that there is not left to right issues seems to back up your cooling idea. My guess they now have antifreeze for sitting over the winter, he used to run maybe just some type of water in all of them? I'll find out.

[Bobby DiDomenico]

Exhaust manifold issue, any ideas on what could have caused this? Is a weld and machine a lasting repair? There is just a small area of material connecting the top and bottom portions that I'm estimating to be .125 deep. The exhaust valve to the right was the one with the worst seat issues. You can see the gasket is no longer sealing on the top of the ports where the manifold portions are no longer in line and eaten away.

[Tom Goldman]

Blast clean it to remove the carbon and pre heat to around 500 deg to help cook out any remaining carbon.
I TIG repairs like that using NickelCast 55 stick rods with the flux removed , makes a very nice ,durable repair ,especially on old castings.
I've used this method for blocks , heads and manifolds.