Digging for info - front drum explosion on 727s

a70duster said
Great discussion going on. Here is what I got so far.

- Any 727 can grenade the front drum
- A drag car should start the burnout in 2nd (manual valve body)
- No dry hops (I'm not on board with this, it is just like a launch and confirms that you can do a 100% launch)
- Launch a car in 1st (Low/Reverse band applied)
- Don't lift and get back into the throttle while in 1st (this would be hard to overcome, this is an instinct for a gearhead)
- Use a valvebody that applies the Low/Reverse band in 1st
- Wrap that rascal

So if the sprag is the problem and isn't being used in 1st, can the transmission be run without the sprag when running a manual valve body?

The only danger comes into affect is when the Low/Reverse band doesn't get applied when in first.

The sprag is an overrunning clutch which is the holding device that locks the low reverse drum from spinning counter clockwise when in first gear. In second and third gear, the low reverse drum spins freely clockwise and the sprag is “overrunning” at that point. With low band apply valve body, in first gear, you are applying the low reverse band to also hold the low reverse drum in addition to the sprag holding the low reverse drum. Yes you need a sprag to run the transmission. A 6 bolt 16 roller sprag is stronger than the stock 12 roller sprags which do not bolt in, and is also stronger than a 4 bolt 12 roller sprag. The extra 4 rollers give more locking power while in first gear and the bolt in outer cam helps support the load the sprag sees as well.

Yes the stock front drum is what explodes if the sprag were to fail. I have heard of others seeing aftermarket drums exploding, however, I, myself have not witnessed or heard of a aftermarket billet front drum exploding

Personally I do 2nd-3rd gear burnouts. I am in second gear for only the hit of the throttle then immediately into 3rd gear. I do no dry hops and still manage to hook my car up all the time. 1.18-1.21 60’. A dry hop is just placing extra load on your entire car. But if you feel it is necessary, have at it, although I would steer clear.