Last night I put a new head gasket on my 91 dx, This car has an 89 si motor, but the head was bad so i used a 91 si head i had, the valve adjustment is perfect at TDC, and every thing looked perfect. I started the car up and it runs like ****. I had my buddys dad check what i did and he told me the timing was fine, but what else may be the problem if the timing is on and it will not stay running for more them 10 sec? I used a new dis. cap and rotor with new wires( all 4 cyl. are firing)....at this point im open to ideas! thanks