I need help!!!

This is whats going on

My car is running hotter than normal and it feels like it is lacking the kind of power it should have. I just rebuilt the engine and it feels like it is lacking low end the most but overall it doesnt seen like it has any more hp than the wore out 302 that was in there. The machine shop says it sound like the timing gears are a tooth off but I double checked it putting the engine together. It revs fine, starts fine and drives fine but just lacking power. when I advance the timing more it runs a little cooler. All I have is the stock "NORMAL" gauge.
At 12 btdc it runs at the M and at 18 btdc it runs at the R. I really dont want to pull the timing cover off and im 99% sure the dots lined up on the timing gears.

This is what im working with
302 .030, trw 10.1, total seal rings, gt40 heads, b303 cam, 1.7 rockers, mallory ig, edelbrock manifold and carb.

Ive been tuning all day and the only thing that changes is the temp. Is there anything anybody can suggest before I tear the entire front of my engine apart??????? If you want to talk to me just pm me and ill give you my #.

Check for vacuum leaks first

I guess you could pull your passenger side valve cover off and make sure both rockers are down (on the base of the lobe of the cam) when your balancer reads TDC. That would be way faster than yanking all the shit off the front of the motor. If they're not both pointed down when your pointer hits TDC, then you know what to do.

Is that a brand new thermostat?

Thermo is good, What im really trying to figure out is shouldnt the car run poorly if the cam was a tooth off instead of just not having enough power?

Might be running lean. pull a plug and see if there's any color to it.