Slant 727 WIW
It's a well known fact that 727s DO disintegrate the STOCK drum if it exceeds a certain RPM......and that RPM is not difficult to achieve. Perhaps that's what Bill's friend was referring to. You obviously are very knowledgeable yourself. I was merely pointing out that your points would be better gotten across without the name calling. That's all.
I have been a cyber-junkie since before the Internet existed, serving as the Moderator of the Prodigy Drag Racing Bulletin Board (no kidding!) for a few years before the Internet came online. I say that to emphasize the fact that the thousands of hours I have spent talking to people online has resulted in my having developed a VERY thick skin as regards untoward comments and all the different negativity that crops up on these glorified chat rooms. A lot of it is due to the limited ability of the Internet to convey inflection in comments, and a lot of mis-understanding goes on that would never have happened in face-to-face conversation. Comments made off-the-cuff that would go unnoticed in personal verbal exchanges stand out like a sore thumb on here, and create hard feelings where none is intended.
That's one of the serious flaws in Internet communication... unintended meanings that come through in spite of the best intentions.
I, having been a cyber-junkie for so many years, have seen this so many, many times, and the result of it, tend to ignore it, because I know that if it were a face-to-face, REAL conversation, it probably never would have happened.
So, I usually just ignore it... 'cause it usually wasn't a real, sincere comment...
But, getting back to the 727/904 discussion, the exploding clutch drums in the 727's I am told, are the result of over-speeding of that cast iron cylinder due to the sprag anchor in the rear of the case becoming dislodged and losing its ability to over-run. This excessive rpm creates centrifugal forces that the drum was never designed to withstand, and it explodes as a result. Apparently, the sprag anchor in the 904 doesn't have this problem, so explosions of 904's are pretty much unheard of. That is not, however, the situation Len told me about that is involved with the parts of a 727 being so over-built and heavy that the rotational inertia causes the transmission to damage itself, when subjected to high rpm shifting. That cast iron drum, I believe, is stopped dead, after being spun to a high rpm in 1st gear, imparting severe inertia-loads on the shafts, planetaries, etc.... That is what he was talking about. It's not a problem that would occur in daily street driving.
I tried to call his shop just now, for more specific information (I am a transmission idiot) but he wasn't there right now.
He has resumed racing in NHRA's Super Stock Eliminator, after about a 7 or 8-year layoff due to his particular engine receiving a lot of horsepower from the "
Automatic Horsepower Factoring System' (a method that NHRA uses to adjust factored horsepower on combinations that seem to need it.) The extra horsepower put him at a severe disadvantage and moved him up a class, so he took a hiatus and eventually built an engine that has different specs, so has no increase in factored horsepower. He runs in a GT class, which gives him the ability to use a variety of different engines, legally.
I'll try to get more information on that 727-inertia problem at some later date.
