but the car wont turn over and when it does it just stops. IDk what's wrong with it also when the car turns over out of the header smoke comes out and smells like firework's does anyone know what could be wrong?

 

check your wiring

 

we checked it twice and everything is good

 

Car won't turn over?
That means your starter is bad... If it turns over but doesn't fire.. thats not called "won't turn over".
That's called "won't fire"

Otherwise, ounds like you're flooding the engine, it's burning in the exhaust, and your exhaust manifold gasket is shot if smoke manages to come out at the head. (it you mean at the tailpipe, thats ok.)
Are you leaking fuel at the injectors?

Could be your firing order, could be the distributor itself. Or your distributor wiring.
What codes are you getting after you crank it over a few times?

 

the car turns over a couple times but when it does after a sec it stops and thats it

 

Did it turn over before you did the DX to SI swap?

I would check the Ignition starter switch. Located on the backside of where you put your key in to start the car.

 

when i had the dx engine in it started fine i was riving it when i put the si engine in it did this ill check the ignition