Don’t need to be doing low gear hi rev burn outs. Get the rear tires spinning go to second gear. Been running 727 for over twenty years. Never once exploded one! Most of those years with a trans brake !!View attachment 1715534530 View attachment 1715534531 View attachment 1715534532 I saw this on Classracer, a tranny explosion at Numidia today. This is why, as much as a pain in the a$$ they are, you need to run a blanket or shield. I don’t know if this car had one, but I doubt it. I have no idea how fast this car is, my guess it’s just above the 10.99 e.t. that requires one. Most likely a 727. I could be wrong, but I don’t think 904’s explode like that.
Most are self caused
Never seen a 904 drum explode.....
Lighter weight, smaller diameter. Not sure how fast it would have to spin to disintegrate one of those. Never heard of it happening.
Curious why 2nd gear for burnout ?
So I’m pretty new and go into the box with my auto shift 727 sitting in 2nd and think I’m ok because I’m in manual 2nd. No, the car is in first. There are just too many variables to make blanket statements about how to run a 727. have!
thought i saw Cope was working on oneIt would be great if some one made a SFI approved 727 case.
no one with any kind of power should be racing with a stock cast iron front drum period.
You can bevel the edge of the rollers top and bottom!! Then you can double spring every roller ! Install a harden bolt in outer race !! This will help with making the rear sprag as strong as it can be ! I tore up my forward planetary. When I tore the transmission down I found that my bolt in sprag outer race had a crack in it !! So anytime you go into your transmission you need to check that sprag and all the pieces to it !!See above. Shift into second before getting out of the burn out. A bolt in sprag with extra rollers and a valve body with low band apply are good upgrades.
I recently had a sprag let go while lightly accelerating through a light. It locked the back wheels up very violently. It destroyed the sprag but luckily the case was still intact. Numbers matching 340 car so I was very concerned the case was going to be toast.
Hope that driver didnt loose any toes!
Yeah a 904 can do this too. It might be less common since the drum is much smaller.
View attachment 1715534530 View attachment 1715534531 View attachment 1715534532 I saw this on Classracer, a tranny explosion at Numidia today. This is why, as much as a pain in the a$$ they are, you need to run a blanket or shield. I don’t know if this car had one, but I doubt it. I have no idea how fast this car is, my guess it’s just above the 10.99 e.t. that requires one. Most likely a 727. I could be wrong, but I don’t think 904’s explode like that.