In recent years, we have heard of many enthusiasts having ignition control module failures. Most of these complaints come from the plug-in replacement "Orange Box." When reading through most any Mopar related forum, looking for an upgrade, the usual answer is a Mopar "Chrome Box."

Now we have another option that allows you to simply plug in a performance unit, and it comes with a nice added feature of a rev limiter to protect your engine. Named the Rev-n-Nator, this unit uses your same factory wiring harness and stock mounting location. It comes available powdercoated in black for a stock look, or orange to appear similar to the Mopar Performance box we are used to seeing. The Rev-n-nator is a true plug and bolt-in (almost) factory appearing I.C.M. (AKA: Brain Box). What makes it better is that it has been completely re-engineered with digital technology! And since we said almost factory appearing, we have to make mention that it has a simple to use built-in rev limiter that is visible on the outside. The rev limiter is not visibly detracting, but it will let anyone know that it's not a stock unit.

The rev limiter has seven different rpm limits ranging from 3,000 to 7,500 rpm. The limit required can be changed by a simple touch of the button that's on the face of the box. You'll know what rpm you have selected by the easy to read LED lights!

To protect your engine from over revving, the Rev-n-Nator is the perfect bolt-in piece to keep your engine from developing an unnecessary ventilation hole. There are no extra wires or boxes required, and it is a true bolt-in and go unit. This is not just some rebuilt unit either. It features all-new digital electronics, but it is in a stock box.

We recently had the opportunity to compare one of these Rev-n-Nator boxes against several other plug-in replacements, and comparing the different boxes against each other on an engine dyno allows us to see if there truly is a loss or gain between them that might go unnoticed on the street or even at the dragstrip. While traction, weather, convertor slip, etc. can come into play, dyno testing in a controlled environment can reveal some things that might go unnoticed otherwise.

We did our testing on our 421-inch small-block with a factory type plug-in replacement box from Wells Electronics. This is your basic auto parts chain retail item. Having run several other tests on this engine in the past, we knew it was down on power with the stock box, but we needed a baseline to do comparisons on the various ignition boxes. With an average torque output of 488.7 lb-ft, and an average horsepower reading of 463.3, we knew it would not be hard to improve upon. The main issue with the Wells unit was the fact that the engine had some serious issues trying to accelerate above 4,500 rpm. With the basic replacement box, the best overall performance was found with total timing set at 32 degrees after several pulls.

Stepping up from the economical, replacement type ignition control to a Mopar Performance Orange Box was as easy as plugging it in and checking the total timing again. We again settled on 32 degrees total timing, and performance was noticeably better with averages of 498.8 lb-ft torque and 473.2 horsepower. That is 10.1 lb-ft of torque and 9.9 horsepower, just by adding the Orange Box. The huge hole in the torque curve was gone, but there was a "step" in the curve near 4,000 rpm. We had previously heard that the Orange box pulled timing out of the distributor at that rpm and checked to be sure. Sure enough, timing had been retarded by 5 degrees. We wondered if that timing loss could be compensated for with more total timing, but several attempts to add more timing, with either more initial or more mechanical advance, caused audible detonation.