Myth Busters, Part 4

Last in a four-part series

In the last three articles we looked at the evaluation of torque converter modifications on a chassis dyno. The modified converters were compared to an OEM converter, and the testing was done by Sean Boyle and three of his students at the University of Southern Illinois. A MD-250 Mustang Chassis Dyno was used for the evaluations, and a Dodge Durango RT, equipped with a stock 5.9L gas engine and 46RE transmission, was used as the test vehicle. All the converters were subjected to wide-open throttle (WOT) horsepower tests. The vehicle was locked in third gear (direct drive) and TCC lockup was inhibited.

The first modified converter tested (converter A) had its stator modified in a manner that lowered the stall of the converter, and the vehicle responded favorably. The modification probably would have enhanced the vehicle’s fuel economy and towing capabilities. The next two converters, B and C, had modifications that raised their stall. Converter B had .175” machined from the turbine side of the stator. Converter C had its internal clearance (impeller to turbine) doubled, from .080” to .160”. Both of these converters may have been an enhancement for a modified engine, but neither performed up to the par of the OEM converter behind the stock power plant. To make things worse, both of these converters had elevated temperatures that would have required additional cooling with continued use.

To read the rest of this Technical Article on the Sonnax Website click here.

Article No.: TCTIP-08-07
Author: Ed Lee
Total Pages: 3

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