Has anybody ever seen anything like this, it was a brand new gasket 160 miles ago...what may have caused that??

 

ethanol fuel?

 

Yah, stuff around me all has up to 10% ethenol.

 

Holley gasket?

I ran 85% ethanol and didn't have that problem. Looks like a combination of misalignment and over-tightening to me.

 

Everything, for all practical purposes, in the US has at least that, nowadays.

Looks mostly like over-tightening to me.

 

Pictured here is the brand new Holley non-stick gasket i put on last night, drove 20 miles tops and then pulled it. It appears to be deteriorating the gasket.

Fairly snug with a 1/4" drive ratchet, maybe i can be a little less aggressive in my tightening for new gaskets, im doing nothing more than what ive done all my times working on carburetors. But gasket looks to have been dipped in acid.