Race Engine Building - Speed Parts Upgrade

Whether your engine uses the... 

   

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Whether your engine uses the down-and-under plug cable routing, as per this Cup-level Dodge motor, or the over-and-down routing, the new Accel 10.8mm cables make neat installation a breeze.

Part of my mission is to make any engine I build that's likely to be in a magazine article-about 95 percent of my builds-look good. This means detailing a lot of parts to a far greater extent than normal. Of all the parts that make up a finished engine, the plug cable loom is among the most difficult to tidy. In addition to this, there is also the question of routing for best survivability against the ravages of radiated header heat.

Most engine builders handle both appearance and thermal overload survivability with various designs of bracketry intended to hold the plug cables in a suitable position. However, a move by Accel may not only spell the demise of plug cable bracket/loom supports, but also make life considerably easier when producing a good-looking plug cable loom.

How has this come about? In an effort to boost insulation characteristics, Accel increased the outside diameter (OD) of its race cables from the more usual 8.8 mm to 10.8 mm. Apart from the OD, it seems little has changed. Accel has made its race plug cables too big to fit any of the plug cable loom hardware that is currently available. But what at first seems to be a step backward turns out to be anything but that.

It's easy to see the difference... 

   

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It's easy to see the difference between the regular 8.8mm cable and the new 10.8.

Normally, part of the job of a plug cable loom is to keep the cables apart to discourage the spark energy of a firing plug from jumping across to one that should not be firing. By making the insulation 2 mm thicker, cables that are actually touching in a bundled fashion have no more tendency to transfer energy from one cable to another than a set of 8.8mm cables separated by a 1/2-inch air gap. What this means is that instead of using a cable loom supported by various brackets that locate and separate the cables, we can now zip-tie them together as a bundle. This not only facilitates making the cables look neat, but also allows the cables to become a self-supporting set that stays put. This, in most instances, eliminates the need for any additional mechanical support for the plug cables.

The 10.8mm cable has enough... 

   

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The 10.8mm cable has enough extra insulation to allow bundling of the cables without crossfire occurring. This makes a very neat plug loom just by using cable ties.

The world of spark plugs is not without its share of seemingly odd-looking pieces. The claims usually made as to what some of these unconventional-looking plugs can do is usually only in the mind of the writers of advertising copy. That, however, does not mean that every unconventional-looking plug is potentially a marketing ploy to get you to buy that particular company's product. Having been personally involved in some spark-plug development projects, I can say that a key issue is for a plug to be able to fire easily and to produce as much spark energy as possible in the gap. That sounds reasonably clear-cut, but the problem is that, to a large extent, these two features are mutually exclusive. It seems that as more spark energy is produced, it becomes more difficult to fire the plug. Assuming there is not a design flaw at work, a plug that requires a lot of energy to fire is one with a big gap. However, it is possible, by means of a less-than-conventional electrode design, to produce a spark plug that is easier to fire yet produces more energy in the gap than a regular plug.

There have been many variations... 

   

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There have been many variations in plug-tip designs, but chances are, the tip of this E3 plug is something you have not seen. Our tests have shown a power advantage when this plug is used in a crate engine.

Even at a glance, the E3 plug's electrode design is anything but conventional. Typically, I would not contemplate testing a spark plug at my own expense, but some of the features of the E3 plug are similar enough to those that worked during my time involved with plug development. This prompted me to test these plugs in the crate motor that normally powers Nick Losito's No. 64 car at Hickory (North Carolina) Motor Speedway. The results are shown in the accompanying chart (Fig. 1). This test was fairly realistic, as we had already gone through a number of different plugs to see which would work best. Up to this point, an Autolite plug had consistently out-powered everything else we tried. The E3 plug beat this. It appears that it lights off the charge a little faster, as a little less advance was needed (in this instance) to get the best results.

The baseline Autolite plugs used in the test produced two more horsepower (but sometimes more) than most other plugs we tested. However, plug testing can reveal some unexpected results inasmuch as one or two brands that work perfectly in a similar engine don't pass muster and could be as much as 10 hp down.

What have we proved here? One, there is no such thing as "the ultimate" in anything. Everything can be improved. Two, we have found that this plug works fine in a stock engine. That does not mean it works in everything right up to a Cup-level engine-that has yet to be determined from more dyno testing. These plugs look like they are worth a try in other applications, but do whatever "trying" might be involved on a dyno to be sure the power has been moved in the right direction. For what it's worth, I think they may work best in Street Stock applications or any induction-restricted, moderate compression type of engine.