So I have an rb20det redtop and a no start condition. Wiring specialties rb20det to s13 harness. they say it works for late model redtops and all r32 rbseries engines. I have spark at the coils.but no combustion, engine cranks but does not turn over. spark plugs are decent, have compression, transistor/ignitor chip is good, fuel pressure is good and lines are correct, z32 maf bypassed the turbo and installed it on the intake elbow. Throttle position sensor Is digital I believe and only the idle connector is plugged in:\ but I don't think that should cause a no start tho, and I have a vehicle speed sensor code
Probably because I'm using the vss from the ka. other than that what else, any ideas would be greatly appreciated

If you have spark at the coils, check that you are getting fuel.

I have fuel and fuel pressure, injectors are at proper resistance values. They dont seem to be grounding at all.

Are both grounds hooked up towards the rear of the motor? And have you checked all of your grounds for proper connection?