1996 240sx will not start

[Sideways s12]

A buddy and myself have just completed a ring and valve seal job on a 1996 s14 auto trans and the car will not start it has fuel it has spark timing is on target per the fsm everything is on spec all sensors and plugs are hooked up but it will not fire, and we have no idea why my buddy seems to think it's low compression because the rings havent had a chance to seat but it doesn't sound like low comp to me. It cranks hard but will not fire like something is missing. Any help will be greatly appreciated and there is somewhat of an urgency to this matter because the owner of the car needs the car back asap so the quicker the response the better thanks

[rioredstang]

Sounds to me like you have it timed 180 out. Pull #1 spark plug out, install compression gauge and bump starter over till you have compression on #1 cylinder. Remove dist cap and look to see if rotor points to #1 on the cap. I have been working on cars for 30 years and just did the same thing on my race motor. It can happen to anybody. Check this and get back to us.