I was going to hook up a TPS switch as a saftey so I only actvate N2O at WOT and i wondering if the NX TPS sending switch (NX-15961) would work on lt-1's. On their web site they say it activates at 4.0 volts or higher. is that what the stock TPS is set at for WOT.

 

The stock TPS gets a 5V reference signal from the PCM. It will fluxuate between 0.2-4.9 depending on throttle position.

0.2 +/- is at idle
4.9ish is WOT

I haven't used the NX TPS, but I am looking very hard at the Maximizer which uses that switch.

Either way, remember to solder your connection then seal with heat shrink wrap... any crimping with butt connectors or taps will eventually oxidize and affect readings by adding resistance.