Ok, much thanks for all the input. I removed the stock heads from the 360 yesterday and as we thought (see previous post on 360 low compression in #1 cylinder), my #1 ex valve was burned and had a hole in it. So I am going to swap heads. My 360 has pistons with with recessed valve slots in the top not flat top type. The look exactly the same as the 65 t-bird pistons. I am hoping to God that means I have a higher compression 360 then what has been posted. I'm short on cash and can't afford to mess with the bottom end right now. I just want to get my truck running again. Can some one explain the process of determining compression ratio to me? When I test compression on the stock 360 before head removal I was getting 135-140 readings at all other cylinders. That seemed higher then 8.5 to 1, right??