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When it came time to install our D.U.I. distributor we naturally weren't going to use our existing dirty set of wires. Poor plug wires can misfire and kill any benefits of the high voltage spark output. Furthermore, we needed a rugged set of wires that would hold up next to the 460's big header tubes. As a result, we went with Performance Distributor's own LiveWires. The hefty 10mm spiral wound wires have a very low resistance of 300-350 ohms. A nice plus is the integral heat-resistant sleeving which will prevent burning on headers. With this much juice getting to the spark plug you can increase the gap to 0.055" to get a nice big spark to light off the cylinder charge.

This flat-sided thermostat housing may be neccesary to clear the large distributor.

The larger distributor body may cause clearance issues with wide diameter drop-base style air cleaners.

On the dyno we placed the D.U.I. up against a new Motorcraft™ dual point unit, to see the difference versus a stock distributor.
Installing the D.U.I. distributor is straight forward. On some 460 engines it may require the installation of an offset thermostat housing, available from Performance Distributors. The cast-iron housing is machined flat on the side facing the distributor in order to provide clearance for the larger diameter cap and housing body. We also experienced slight intereference between the cap and our drop-base air cleaner, required due to the tall plenum height of our Weiand Stealth manifold. For the dyno testing we ran without an air cleaner, however for the road we will use an offset base or a shorter diameter cleaner.

As mentioned previously, the big advantage to the D.U.I. is the wiring simplicity. We took the 12V positive lead which once ran to the positive side of the stock coil and simply attached the supplied female terminal connector to the D.U.I. unit. We also took advantage of the D.U.I.s tach output terminal and wired up our Autometer tachometer for accurate rpm monitoring.

Dyno Testing

During the dyno testing of our Streetwise 460 motor we made initial baseline pulls using a new Motocraft™ dual-point distributor and coil. To emphasize "as delivered" conditions we made no changes to the advance rate or curve on the stock distributor. We installed the stock distributor with 14 degrees initial advance and checked the total advance on the stock distributor to be 34 degrees, coming in at 5000 rpm. The slow advance rate of the points distributor showed its' weakness in both street driving as well as dyno testing. Throttle response was rougher and the engine was audibly slower in reving from 2500 rpm to 5500 rpm on the chassis dyno. Results show power down all across the rpm range (see chart below.) Perhaps more telling is the A/F ratio which is noticably richer, indicating incomplete burn in the cylinder.

While the engine cooled from its' baseline runs we dropped in the D.U.I. unit and reset initial timing to 14 degrees. We checked total advance and found it to be 36 degress at 3000 rpm, exactly what the paperwork accompanying the distributor indicated. Furthermore, unlike the points unit, the timing light showed dead steady timing marks at 3000 rpm. The engine fired right up and a few blips of the throttle indicated a snappier, crisper sounding 460. The motor responded to the D.U.I.'s advance curve and fatter spark with 25 horsepower at about every rpm point from 3500 to our self-imposed redline of 5500 rpm. Torque was up equally as well. A review of the air-fuel ratios reveals a leaner mixture, indicating more complete burn in the cylinders. The average air-fuel ratio at wide open throttle went from 12.3:1 to 12.9:1.

The results clearly show that whether you are building a motor back to stock, or for performance, it pays to upgrade from the stock distributor. Not only is there power which can be unleased, but we're adding in reliability as well. The D.U.I. gets our vote for a custom curved high-output ignition system that installs in minutes without complicated or messy wiring. We've got high hopes that this system will stave off Murphy's Law for a while - at least when it comes to firing up our 460.

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When time came to install the LiveWires we found that Performance Distributor's makes it easy by clearly numbering the wires. The pre-assembled lengths were very accurate as well. The heat resistant sleeving used on Live Wire's is neatly secured under the silicone boots.


























Performance Distributors
2699 Barris Dr.
Memphis, TN 38132
Ph: (901) 396-5782

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