hard engine-braking in second gear- will this wreck a 904/727?

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MRGTX

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I've been spending every free minute of my life in the garage lately and I'm hoping to be ready for some autocross before the end of the season. Someday I will have the resources to swap in a proper manual box but that's going to take me years to save up.

So I still have some unanswered questions about running this car, not the least of which is what's going to happen to the transmission under typical autocross flogging. I am running an A904 with some upgraded internals and a deep pan but no manual-shift valve body and IIRC, a stock sprag assembly. Probably also worth noting is that the transmission is spinning a 4.10 axle.

Often in autocoss, the transmission (auto or manual) would be left in second gear which means that you alternate between heavy throttle and closed throttle often. This can often be a means to get the car to rotate through some engine braking forces on the rear wheels. Also with a V8/rwd car, there's a very good chance for lots of tire spinning at various points on a given autocross course.

Will these conditions spell certain doom for a Torqueflight? Is this asking for sprag-destruction?

Currently, I'm sliding around on no-season BFG T/As but at some point I will have the cash for some modern/sticky rubber. Safe to say that the risk of damage will only go up?

Thanks for any insight/experience!
Mike
 
The 904 intermediate band is sorta narrow. But there are kevlar bands on ebay for cheap, plus maybe you could fit in a 1.6" band to replace that 1.4". You could get creative and even install a much wider band just offset the struts; a la sixties Cruisomatic. I'm fitting a 2" FMX kevlar band into the 904 by offsetting the struts. It overhangs the front of the drum a bit.
 
If your staying in second your stressing the front band, not the sprague and I agree with the above about the front band. Your asking a lot from it considering it's size. I used one for an early 90's A500 in my 904. Think it's was around 1.6" wide. Got it in Kevlar too so it'll take the abuse. Their dirt cheap is the good part. Also tighten up the end play to as close as .020" as you can get it so the stator rings aren't working back and forth so much. That rounds the edge of them off and they lose sealing ability
 
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