Installation and Testing - Project 11.99
We first installed the Pro-10 in our '67 coupe (Project 11.99.) The Pro-10 was actually mounted along side the MSD 6AL system we had been running. We set up the wiring so that we could switch back and forth between the two setups rather easily. This way we could compare the two boxes "side by side" on the street and at the strip.

We mounted the Pro-10 across from the MSD 6AL so we could easily switch between the two.

The Jacobs gets two thumbs-up for ease of electrical connections. Their "EZ" connection system truly lives up to its name, we had to perform zero splicing, crimping, or soldering to get the system running. The Pro-10 comes with all the connectors pre-attached and plenty of wire length to mount the box just about wherever you may wish. All the connections were made under the hood -no searching for key-on power sources in the fuse box or ignition switch. This is a huge plus in our minds, and we can't say enough good things about how easy the hookup was. As for mounting, we choose the fender panel typically occupied by the battery (ours is in the trunk). The Ultra Coil is pretty beefy and will require a little creativity to mount. Fortunately Jacobs includes a really long coil wire, so we mounted the coil below the energy pak, on the frame member.

With the Jacobs mounted and running in Project 11.99, we headed up to Sacramento Raceway for some comparative testing against the MSD 6AL we'd been running to date. The approximately 200 mile round-trip drive to and from the track would be as much a part of the testing process as the strip itself. We wanted to test all of Jacobs' claims, especially better fuel economy and less plug fouling -two problems our 400HP 302 is plagued with due to the poor vacuum signal at cruise with the single plane intake and 750 cfm double-pumper.

Unfortunately we ran into some problems with the strip testing of the Pro-10. On the first run down the track with the Jacobs, the engine felt like it was not pulling beyond 4500 rpm. For an engine that makes peak power between 4000 and 7000 rpm, this meant a serious loss of power. We suspected a timing problem, and further investigation revealed that our total timing was only about 28 degrees, rather than the 40 degrees had it set for. Our initial timing was where we had set it, at 18 degrees, so we suspected either the distributor advance mechanism had failed, or the Pro-10 was doing something strange to our advance curve. We quickly swapped back to the MSD to try to isolate the problem. With the MSD the timing was back to normal, indicating something was not right with the Pro-10. We tried resetting the rev-limiters, disconnecting the tach, and checked the connections but no luck. Frustrated that we couldn't get full timing, we tried one last ditch attempt by bumping timing up to 30 degrees initial. This way if the Pro-10 was only allowing 10 degrees centrifugal advance, we'd still get 40 total. We made one pass and actually ran 12.12@114, in line with what we were running with the MSD. Nevertheless we weren't satisfied with the results, and decided to call it a day and check with Jacobs for troubleshooting tips.

Discussing the problem with an engineer at Jacobs, we learned that the problem we were experiencing with timing cutoff was due a signal conflict with the magnetic trigger in our MSD distributor. The MSD distributor uses the same variable reluctance magnetic pickup mechanism as found in Ford Duraspark distributors, however without the Duraspark box. While the Pro-10 Energy Pak is set up to work with all distributor types, it apparently requires an high-level signal from the Duraspark module. The solution, Jacobs tells us, is to wire a Duraspark module between the Pro-10 Energy Pak and the MSD distributor. We haven't had time to round up and install the Duraspark box, and frankly we feel you shouldn't have to install additional components to get a system to work. Jacobs tells us their new Fire Control Ignitions which are just hitting the market have this problem resolved. Next time Project 11.99 hits the track, we'll install a Unilite or Pertronix mechanism and try the testing again.

To our surprise, the Jacobs did produce significant improvements in fuel economy. Normally this engine averages a very consistent 9 mpg, on 92 octane, on the drive to and from the strip. With the Pro-10 running in place of the MSD, we averaged between 11.5 and 12 mpg during the 200 mile freeway drive. Thinking perhaps this was a fluke, we monitored the fuel economy again the next trip to the track, and got the same results on the way up. On the way back, we reconnected the MSD, and mileage was back down to 10 mpg. Furthermore, plug fouling was reduced with the Jacobs Pro-10. After idling for several minutes, the plugs on cylinders 1 and 5 typically look black, however with the Pro-10, the plugs were a light brown (still darker than the other cylinders, but not nearly as bad.) While obviously a subjective statement, it is worthwhile mentioning that throttle response with the Jacobs system is noticeably "crisper" and smoother.

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