This is my second blown HG. The bottom end of the engine is all stock. The head is EB and only has around 25,000 on it. Everything was perfect before the 2nd blown HG.

Yes, there is a power loss that I can feel. There was no appreciable carbon anywhere due to having been in it and cleaned it not that long ago.

I ordered the standard thickness gasket. I'm not sure, but I doubt the thick one would lower compression by that much.

I carefully set valves.

I'm not driving it much right now, but when I do I'll look for any weird smoke coming from the exhaust.

Seems to me a bad HG or valve would not cause all cylinders to be low in pressure. One possiblity is the timing chain is not installed correctly (crank gear marks and cam gear marks must line up). That would affect all cylinders equally and affect power.

1984 4Runner