New Ignition and Data Collection

I am installing a new ignition system on the car because I found some issues with the old MSD Digital 7 ignition.

I am pretty sure that I was losing a lot of horsepower (the car should have run faster than it did) due to a programmable ignition retard that was not working correctly. I am pretty sure that the ignition was retarded at least 8 degrees from optimal because the programming did not work with the new starting line controller. The retard is supposed to start as soon as I press the transbrake button (that works correctly) but is supposed to go away over a period of one second once I release the transbrake. That ramping down of the retard was not happening because the program logic requires that the engine be on the rev limiter when I release the transbrake button. The new starting line controller does not let the car hit the rev limiter because it is pneumatically controlling the throttle, therefore, the ignition stayed retarded through the runs.

I found this while checking everything over after the races a few days ago. I observed it while I was checking ignition timing with my timing light. I was verifying that the retard was working but I noticed that it never went away. Further investigation and a talk with the software guru, Joseph (our business partner) and some testing led me to believe this is what was happening. This, and the fact that the car is not running as quick as it should led me to modernize the ignition.

The new ignition (MSD Power Grid) gives me more control over the timing curves and rev limits. It also allows me to capture the timing data from the ignition controller in the Racepac data collection system.

I will be able to look at timing curves with other data from the runs to see what effect the timing is having on the engine.

The two pictures of the chart show a test run after installing the ignition. You can see the engine RPM on the top green line on the chart. You can see timing advance on the second blue line. You will notice that I have it set to ramp up the advance as engine RPM go up. The third red line is showing the transbrake button being activated (upward line is the switch turning on and the downward line is the switch being released. Notice that the ignition line shows the ignition retarding 10 degrees when I push the transbrake button. When I release the transbrake button, the ignition ramps back up to full advance over a 1 second time frame. This is what was not working with the old ignition. I can also adjust how long for the ramp up to happen. If the car spins the tires early, I can slow down the advance to kill some power. If the track will take the horsepower, I can advance it sooner.

Being able to look at these events with all of the other data that I am collecting will make it much easier to tune the car.

I am anxious to try it out. There is another race at Royal Purple Raceway this weekend and I am going to try to go and get some more seat time. Wish me luck!!!

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