DragStuff

Anyone ever seen this type of corrosion on heads / intake manifolds? I believe it's only happening where the surface contacts the gasket and not near the water outlet - this photo is shot from the center of the intake.. Fel-Pro 1275's were what was used. Don't recall seeing this last time around. Corrosion looks like tiny worm tracks. It shouldn't be electrical in nature, both heads are well grounded, solenoids have their own grounds as well.

Ideas?

I've seen that before on just about every aluminum intake I've taken off any motor. Working on aircraft for a living I see that type of corrosion all the time. Unprotected aluminum is subject to moisture corrosion and that's what that is. Moisture of some sort got under the gasket that's what caused that.
Now how to fix it. Scotch-Brite is smooth and move on. It's nothing to worry about. Like I said I've seen that on just about every intake I've ever removed from a motor.
Remember unprotected aluminum is subject to moisture corrosion.

Hope this helps

Thanks for the confirmation Chris - That pic is after I had already cleaned it a lot with green scotch bright. I'm going to switch brands of intake gaskets and maybe put a coating on the intake like a coat of paint? Something to help protect that surface some.

Try this. Scotch brite by hand not rotary powered.
Follow up immediately with Gibbs Brand oil.