TROUBLE THE FIRST TIME OUT:
I know that most tech articles always make it seem like everything went smoothly the first time, but not this one. I encountered a couple "strange things" my first day out with the Digital-7. The car started great and seemed OK until I went up for first time trial.

The car just would not run over 4000 RPM. It didn't have any power and ran very rough. At first we thought it was timing but that checked out O.K. Then we shut the car off and restarted it and then we found a PROBLEM. We found out the pin that locks the advance mechanism in the distributor had broken, allowing the timing to change. The first time we checked the timing was 34 degrees. The next time we checked it was 65 degrees!

A friend fired up his welder and welded the advance plate and we thought we had it conquered. Wrong! We tried two more runs and got the same misfiring. That was it for the night and it was back home to see what we could find out.

After talking to MSD Technical assistance we checked the plug wires for resistance. Wow, we had one wire that was terrible and they were only two months old. We installed a set of MSD 8.5mm Super Conductor Wires and off to the races we went. The car sounded great and the burnout sounded good. However, when I reached about 5500 rpm the engine went flat and started misfiring badly so I shut it off.

Now we thought it might be valve springs or another problem. Again we checked everything but it still ran poorly. This time I called Joe at MSD and we went over the entire installation and the problems I was having. When I mentioned I had problems with my distributor he asked whose crank trigger I was running and I said I was using the Magnetic Pickup in the distributor. He said this could be the source of the problem due to the small distributor cap I have to use on the Mopar and the variation in timing the gear drive and cam gear can cause. He said he wasn't sure if there were any Digital-7 ignitions in use that weren't being triggered by a crank trigger setup. We decided to put one on the big block Mopar and see if it helped.

First thing I thought of when I got the MSD crank trigger for the big block Mopar was that I would probably have to do some custom machine work to install it. I have a 5" pulley for the alternator and a crank drive spindle for the belt driven fuel pump I run mounted on the harmonic balancer. Well, the engineers at MSD did their job because the entire MSD Crank Trigger simply bolted on with NO MODIFICATIONS needed. I just followed the instructions and it was done.

Now for the real test - will it eliminate the misfire? It sounds noticeably better in the garage but that can be deceiving so it was off to the track.

This time the car sounded great on the burn-out and even better on the first run as I ran a career best of 10.28 @ 129.60 in some bad air (4030' corrected altitude). Finally, I had the car ready for the ignition. Every feature I programmed in functioned flawlessly and the ignition contributed to my best ET ever.

If you want to be able to change start-line rpm quickly to adjust for starting line conditions, this little box lets you set the 100 rpm increments. All you need to do is use the supplied 9-pin wiring harness, dial in the rpm you want, and it is instantly programmed into the Digital-7. If you want to race with the wire harness plugged in, you can, but once you turn the ignition "on" the rpm is recorded. You can then remove the harness if you want to.

The benefits or additional uses in a bracket car are:

1. Launch Retard feature: If racing in summer on greasy start line or a track that just isn't hooking that day you can program in 6 or 8 degrees Launch Retard to take some torque out of motor. This will enable you to have consistent 60-foot times and improve your chances of winning on a slippery track.
2. If you footbrake your car, you can program the advance curve EXACTLY as you need it rather than hope your advance weights and springs in your distributor are working the same on each run.
3. The micro controller in the Digital-7 makes extremely quick and accurate decisions on rpm limits for shifters, shift light or retard functions. This increases accuracy of ignition rpm controlled devices and results in better consistency.
4. The Digital-7 eliminates "rpm chips" and the chance of them shaking out or not working properly. No more looking or borrowing an rpm chip that only come in 200-rpm increments; just program in rpm you want to within 100 rpm. A more accurate rpm controller by far.
5. If you run a three speed automatic you can use the Programmable Retard to retard the timing after each shift.
6. The shift light is programmable for up to 5 shift points. While not applicable in many bracket cars, it can be useful with some planning in bracket cars.
7. If you add in the multiple spark feature at rpm below 3300 and the extremely high-powered spark at high rpm, the Digital-7 will keep the plugs clean. This means consistent power and with that you have better chance to repeat run after run.

Overall this is the best "package" for ignition I have ever seen. Everything is self contained so external connections are all but eliminated. The options you can program are almost endless. Programming is very simple and I really like being able to set up a couple different programs for the two classes of racing I participate in.

The two problems I encountered were not related to the MSD Programmable Digital-7 Ignition Control, but rather were problems that needed corrected on my car anyway. The ohm check on the plug wires is something a racer should check periodically, especially if the two step or electronics seem to be acting up. The distributor advance breaking was a fluke but I would recommend a crank trigger for anyone who wants to get the best performance out of a high-powered ignition. As for the "problem solvers" at MSD I can't thank them enough for taking the time to go over everything so thoroughly.

In the final analysis I would recommend the MSD Programmable Digital-7 Ignition Control to any racer who is looking for an improvement in reliability of race electronics and a more powerful ignition with a great deal of flexibility for every type of drag race vehicle.

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