I had the guy re-program the chip with two program. One a forced open loop ( no O2 sensor ) and the other a closed loop. It ran good on the open loop until it got hot then began to miss and backfire. The guy at the mustang shop says it sounds like a vacuum leak or miss fire. So I think I have a misfire condition. I am going to reset the rocker adjustment since I wasn't the one to do it when I bought the long block and do a compression test. Beyond that I will try and see if I got a bad plug or wire. If that doesn't cure it I will have to trailer the car down to the mustang shop to get it diagnosed. Why did I get into hotrodding anyway ? At least I got the coolant and fuel leaks fixed, but now I noticed a rear main seal leak