Hello to all.So I am having trouble getting my new to me trans am to run correctly.I just realized it has a nitrous plate at the throttle body with no other evidence of nitrous.Compression is at 145 and steady all the way.It belches out black smoke like crazy and runs rough.I assume someone had nitrous on it at one time.What do you need to run nitrous as i think this may have something to do with my poor running t/a.Thanks in advance.

 

there is no telling. people do all sorts of things. is the plate closed off, or do you have 2 large vacuum leaks where the lines would connect to the plate? is the ignition timing correct, or is it retarded a few degrees for a large shot of nitrous? if the fuel side is still plumbed up, is it dumping fuel into the engine when you go wide open? is the car setup to run a dry shot? large cam with a stock tune? big injectors with stock tune?

basically, if the car was setup correctly, it should run fine n/a. you don't set one up to run good when spraying and poorly when n/a.

 

hes exactly right,

also the previous owner could have put in plugs that were a few heat ranges colder but they would not have that drastic of an effect.

 

yep, id toss in a new set of plug, get rid of the plate and see what it does from there.

 

Is it a TPI car?

"Belching" black smoke is not cold plugs unless they're badly fouled.

Is there any fuel still connected to the N2O setup? You might have something like a leaking fuel solenoid. Otherwise block off any fittings on the N2O plate or remove it, check the fuel pressure regulator, make sure that it has a vacuum line connected and that it is getting a vacuum signal at idle and make sure that the vacuum can on the fuel pressure regulator isn't filling with fuel when running (ruptured fuel pressure regulator diaphragm, it will be dumping raw fuel wherever the vacuum line is connected to).