Pinto Car Club of America

I just picked up a 73 runabout with a 2.0 in it.  Its got a little body rot on the back rear fenderwells (most pintos in this part of Va. do), but its easily fixable.

But I've got a question about my 2.0.  The previous owner adjusted some of the valves too tight and I've got carbon buildup and it won't build up any compression on the #4 cylinder.  I've pulled the head to do a valve job and noticed something interesting.  The title said it had 150,000 miles on the car, but the cam and the lack of piston ridge are only showing 50,000 at the most.  It also has flat-top pistons in it. That leads me to beleive its a replacement engine in the car, or the mileage is wrong on the title.

I know the compression dropped in 72, but did they just use shorter pistons, a larger combustion chamber, or did they use dished pistons?   If they used shorter pistons, how much would I have to mill off of the head to get it back to 71 compression ratio specs?

Any help is appreciated.  Thanks.

-Harry