I asked about this maybe a year ago. Now that I've looked around the PCM tables I feel I may have found the tables I need to do it.

This could work for tuning MORE or LESS timing based off of a resistor in your coolant temp sensor. You could even wire up a harness that allows you to quickly switch between the resistor and the actual sensor.

First find the resistor for the coolant temp sensor that makes the PCM read -16 degrees C.

Then use the -16C tables for "Spark Correction vs. map vs. coolant temp"
Change that mostly to whatever your temp is that you normally race at but for the MAP values of your WOT you then alter that for your nitrous or race gas/timing advance. -4 or +4 or whatever you need.

Then you go through all the other coolant temp related tables (%change to afr/any start up coolant tables etc.) altering all the -16C cells for the operating/racing temp also, so that it acts like it should at it's actual temp.

Now, you've set up your PCM for normal timing with nitrous timing retard or race gas timing advance (more for boost guys)

No, I haven't tested this. But I don't see why this wouldn't work.

Only problem I see is you fools that start up your car in 3 degree weather (if you modify those tables).

What do you guys think?

 

Do it.
Mallory box works for most.

 

Can you think of any issues? It would be a great option for people to have that thrown onto their tune to skip the ignition retard box. For cheap DIY guys or low end nitrous setups.

 

Sounds like it would work out real nice.

 

Your fans wouldn't kick on..... if you left the switch on. At the track you wouldn't want to have to be flipping an extra switch and just leave it on. this would allow the engine to over heat if someone that wasn't paying attention was doing the "mod".

 

I have seen other people do that on other platforms with the IAT spark tables. They either use a resistor in the IAT sensor or an adjustable **** with different amounts of spark advance at different IATs.

Here is an example for W bodies, may work for an F body also.
http://www.zzperformance.com/grand_p...1254&catid=107

 

Most of that could be remedied by having the "switch" in the drivers compartment. Switch on in staging, switch off when pulling off the track. Just like purge, and other nitrous accessories.

Good call on the fan turn ons though.


That's where I got the idea was ZZPs happy ****. I asked if there were tables that would allow for such a thing in LT1s. I was told no, but I think this would work the same way.