We have a 72 Pontiac Lemans with a stroked engine putting out 650 HP and 725 TQ. Street/strip car. We did some blasts on a deserted road to seat the rings in the engine. Car pulled hard in every gear and trans worked fine. We rebuilt the trans same time as engine. It worked perfectly fine during the blasts. On the way home the car would want to lock up in third gear.
We pulled the pan and found small pieces of metal that looked like the springs in a roller clutch/sprag. Took it apart and sure enough the intermediate roller was destroyed. It was the stock 8 element roller.
Trans has an ATI stock rebuild kit #406330. Turbo-Action reverse manual valve body #24141. PTC 5000 stall converter.
Here are some pics:
Stock intermediate roller clutch.
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The inner race of the roller clutch.
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Case of the TH400
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