I was wandering with nitrous you have to pull back time. So is there a way when you arm the system maybe it also triggers another relay to add a resistor or change resistance of a sensor to change timing.

Where I work at we do heavy duty trucks and on the egr vgt engines we have to put a resistor in the oil temp plug on the airport fuel tanker trucks since they never go above 20 and the comp shows a ideal time 0f 95 percent. We do this so the EGR never open because the lines carbon closed. Well it legal because there off road only vehicles that cant be driven on the highway or public roads.

Well this had me thinking that I have a good timing pulled out to be safe and could I do something like this on my 97 so I will have the performance of an all motor tuned when the system is not armed? Also I was thinking about going to OBD1 so I could get tuner cat and not have to send out when I change tires since I have three different back tire sizes in the shed for different needs. Can I do something like this for OBD1 or OBD2

 

You could just use an MSD digital 6. It has a built in timing retard that could be triggered by arming or activating the nitrous.

 

That a good Idea. Just trying to keep as a cheap street project. As the car mag article said about the cheap street chevelle. We are not tlooking at getting the cheapest part or best deal, we are looking at the cheapest way to go fast!

 

Ttt

 

Timing in your LT1 is set by the PCM looking at the cam/crank postition signal from the optical sensor in the OptiSpark, and apply a timing advance that it gets from a table with RPM on one axis and MAP on the other. Sticking a resistor in the circuit isn't going to change a thing.... its not like altering the reading of a resistance type temperature sensor, or the output of a rheostat device like a TPS sensor.

There are a couple ways to alter the timing. One is to "translate" the cam/crank position signal from the optical sensor to fool the PCM into thinking the cam/crank is in a different position than it really is. The "MAF Translator" device from Ramchargers appears to function in this manner, as the top level model will allow external adjustment of the ignition timing. Perhaps switching an MAF Translator into and out of the circuit when nitrous is used would work. They even mention this application in the description. You're looking at $250 for an MAF Translator.

Another possibility would be to alter the MAP signal (a resistance load) to move to a part of the timing lookup table that has less advance indicated. A "resistor" in the circuit could accomplish that, but you'd have to take a detailed look at the timing lookup table, and possibly alter it so that the "shift" caused by adding the resistor to the MAP circuit happened to correspond to a point in the table where you get the amount of reduction in advance that you want when spraying.

 

The easiest way is to go with the MSD window switch and timing retard box.You have to have at least a 6A ign box to do this. Pull 2* for every 50HP of NO(conservative)