I think the grey area is continually growing on this issue.
Many will say a stock 727 is nearly indestructable.
My buddy ran a 388" small block in an A body. Weighed around 3500 pounds with driver.
The cars best et was in the mid 11's at sea level.
Running low 12's at another track, it blew wide open.
![](/ubbthreads/images/graemlins/eeek.gif)
Lucky not to lose a limb. 727 with stock 12 pin sprag, and a non low band apply VB.
My own car wieghs closer to 3800. Running about 1/10 slower than the previously mentioned A body. Same trans, 727 with nlba.
When his blew open, I decided I would go with a low band apply valve body in my car to help avoid the same issue.
When I went to install it, I found chunks of 1 way springs(from the sprague) in the pan
![](/ubbthreads/images/graemlins/eeek.gif)
Pulled it apart. Debris had chewed up the output shaft so bad, I had to replace it. and best of all, there were only 2 of the 12 springs left holding it together. I was 1 hard hit away from blowing mine all over the place too
![](/ubbthreads/images/graemlins/puke.gif)
In anycase, now I have the billet drum, 16 pin bolt in one way, heavy bands and clutches, and low band apply valve body.
I sleep better now.
![](/ubbthreads/images/graemlins/beer.gif)