1967 400 Firebird no compression 2 cylinders

[Tm67bird]

I pulled the head off to fix an exhaust leak. I could not get 54 year old bolts out due to rust. Prior to this, it was getting hard to start and would pop through the carb. I put the head back on and now I have 2 cylinders with no compression. The middle 2 cylinders near the intake crossover. I think I put the wrong intake gasket on because because I had to pull the gasket off and put on what appears to be the correct one. There’s no water mixing with the oil and I have spark to all plugs from the distributor. Did I burn the exhaust valves. ?

 

[melsg5]

Could be warped head or valves.

 

[Tm67bird]

Thanks, can you take the compression check with all plugs out? I put them all in except for the cylinder I was testing and 1 of the cylinders now had 80 of pressure and the other still had zero ?

 

[Classics Fan]

A compression test is best done on a warm engine. All plugs are removed. Install the compression gauge and crank the engine over for at least 3 revolutions or until you see the gauge needle stop advancing.

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[melsg5]

Compression test is supposed to be done with all plugs removed and throttle held wide open.