So, I got to drive my car in some hot weather today to test out my tune.
I no longer get popping on deceleration.
My MAF sensor is reading properly at idle.
The boost spiking problem has been (mostly) eliminated, though I need to test it at altitude still.
When the intake temperature gets ridiculously hot, the 'intake temperature timing compensation' map has been somewhat properly adjusted. Before, it was pulling approximately 3 degrees of timing as a blanket compensation from final timing advance, I have adjusted that to 6 degrees. I also adjusted when it initiated the timing pull to a lower temperature to inhibit knocking. There are four (well, waaaay more than four) tables in my car's computer that determine when my car's computer tells each spark plug to fire in relation to Top Dead Center on compression for the combustion cycle. There is a Base Timing table, a Max Timing Advance table, Ignition Advance Multiplier, and for this purpose, the Compensation table. The Ignition Advance Multiplier is always between 0 and 1, and can be a decimal. 0.5, 0.2, etc.
Base Timing is never modified. Max Timing is always multiplied by the Ignition Advance Multiplier, then added to Base timing. The Compensation is always added in last.
It looks like this: Final Timing = Base Timing + (Max Timing X Advance Multiplier) + Compensations
Sometimes, there are places where there is ONLY timing advance in the base timing, and the Max timing table is 0. So the equation looks like this:
40* + (0X1) + Compensations = 40* timing advance
If my car wanted to pull timing, all it can do is reduce the Ignition Advance Multiplier, so if it pings in the above spot, it would look like this the next time my engine was there:
40* + (0X0.75) + Compensations = 40* timing advance
Now you can see the problem! No matter what, my car cannot reduce the amount of timing advance in some places! When it gets very hot, like 105 degrees, this is exactly what was happening. So, now we can look at the compensations. When it is 106 degrees, my underhood temperatures climb to around 160 or 170 degrees with the AC on max. There is a sensor in the air flow sensor that can see the air temperature, and the computer will use a table to determine if it needs to make a compensation. When it is 100 degrees out, and 152 degrees in the intake, this is what the equation looks like:
40* + (0X1) -11* = 29* timing advance
Now you can see that it is quite a bit happier! My car runs a little rough with that 'little' timing advance, but it is worth it to not have it reduce the timing in all of the Max Timing cells just because it cannot control knock in one part of the mapping. Then when I get on the freeway, it looks like this:
22* + (6X1) -2* = 26* timing advance
Thus, I have retained the ability to drive in extremely hot weather in the summer without effecting my performance in the winter. I also pulled some timing out of the base timing map in some areas because it's kinda stupid having 46 degrees of Timing Advance in some cells with nothing even close to that around it.
Anyway, the next thing I need to do is either get a Cold Air Intake, or make a heat shield for my short ram. Running the stock airbox isn't possible, as it no longer fits. :p
