Just built my 12.1:1 gsr motor. car cranks over and has spark but wont fire. stock obd2 ecu with stock injectors. walbro fuel pump and aem fuel pressure regualtor set at 42 lbs. i checked all the grounds and fuses. and 2 different distributors...anyone?

 

check all the basics. Make sure all your fuel injectors are plugged in, your ignition timing is where it should be, your cam timing is where it should be and your plug wires are in the correct firing order. Try dropping in a new set of plugs that aren't gas washed.

 

I would say cam and crank timing. It will crank over but won't start sounds like that may be your issue.

 

ill go ahead and do that..any other ideas than the basics?

 

Well you should eliminate the basics before doing anything else