Just wondering if there are any ways to tell if nitrous has been used on a car.

 

nothing easy, pull the heads, using N2O is an awesome way to clean out the combustion chamber! If it is shiny smooth and clean, then probably yes.

 

You could also check all the normal mounting spots to see if any holes have been drilled.

 

check the plugs too. if im not mistaken, your suposed to use a colder plug with n20.

 

+1...check the plugs and then take a closer look at the typical mounting spots. Ideally, you might also be able to spot where arming switches, etc. had previously been mounted in the cabin.

 

usually ngk tr6.one step colder.

 

I could tell right away on mine at the dealer. A few of the things I have found include; two side by side holes drilled into the hump between the rear seats and a larger one in the backseat floor, a couple of mounting holes on the inside of the pinchweld underneath, and the needle part of the schrader valve on the fuel rail had been removed. Plus there is a hole in the console in front of the shifter for mounting a switch.

 

It was pretty obvious on the Z28 I bought. It had three switches in the center console, one was a push button on a cable all thats still there.
When i first looked at it the bottle mount was still welded to the back seat bracket and the line was run to the engine compartment. In the back there was a lid with a fernco hose and a 3/8" hole drilled in it.
This was a roller and they told me the engine blew up due to nitrous use.
A week later I had to go to the previous owners house and seen the old engine just a block and heads with a hole burned through an exhaust valve.

I plan to turn it back to stock then start over with bolt ons. I have a new console without holes in it, the only evidence left should be the cut off at the seat bracket.

 

mine had a switch in the ash tray and the mounts were in the back