"No performance 727 should use a stock drum"...that's just ridiculous. And you yourself state that the 727 sprag is only weak under misuse. You talk about the 904 being good enough for the average guy, but in the same post condemn the 727 for parasitic loss, even tho the difference in the quarter mile is .15 of a second. If you can afford an extra $2-3k to gain .15 of a second in the quarter mile, then you are in a distinct minority as far a I'm concerned; and I don't care about your car. I'm on here to encourage home builders to work on their own transmissions; rebuild them, repair them, shift kits, whatever. The problem is that if you make a slight mistake in your rebuild, a 727 is much more forgiving than a 904. The 727 can take more overrlap and slippage than a 904. If your kickdown is out of adjustment, a 904 will fry ten times faster than a 727. And hey, a weak clutch pack is considered a weakness in the real world.
No performance 727 should use a stock drum, that's just rediculous?
See pic, do you value your legs, or your car or your life? Apparently you don't even care about your customers well being.
904s don't do this.
727 sprags are weak under misuse "or improper valve body" or "first gear burnouts, please read the entire post. The 727 sprag uses an inferior
Retention method compared to the 904, rectified with bolt in sprag.
No one condemned the 727 for its parasitic losses. My Cummins diesel needs a 727 and a stock one still isn't quite strong enough.
If you have an 11 second car with a 727 and you wanted a 10 second car, you need to gain small amounts of et wherever you can get them, more compression, more cam, lighter car oh and a lighter trans. I,ll take that .15.
Only you have said that it costs 2-3k(which is it) to gain .15
It does not have to cost anywhere near that.
What was said, is that if you built both trans identically built( identical junkyard builds for example, identical, the 904(no low gear) identical, will be .15 faster
Now as locomotion has said to you the big dollar trans cost this much because they contain all lightweight components.
Light sunshell, aluminum drums aluminum parking gear, rollerized components. A trans like this will gain way more than .15
My dart gained .5 yes .5 with an aluminum drum, 2.74 1st gear and light sun-shell versus a 2.45 727 all steel with a similar converter.
But to be fair, you could buy these same components for a 727, but it will still be heavier. And not every car needs these kinds of parts.
This is not a condemnation of the 727. It's just not the best choice for certain applications.
I don't care about your car either, such pleasantries.
I have built a w2 410 high compression small block.i will still use
My 904. Stroker small blocks with 904s are all over the place at drag strips. The only areas of weakness that I upgraded were I went to an aftermarket input shaft and an aftermarket 30 roller sprag.
I would like to think that most members on here share a common passion, and we are all here to help each other. You are really full of yourself if you think your the only one. You know that you and I both helped a member on here do his very first rebuild last year.
A band adjustment is performed the same way on a 904 as it is on a 727. Clutch pack clearances as well. That argument doesn't fly.
You either know what your doing or you don't.
Regarding shift overlap, the 904 is unique with that problem because of the front drum stock return spring. At high rpm it causes
Major shift overlap compared to a stock 727. This is easily rectified
With the aftermarket multi spring pak. I through in a pic of a blown up Chevy as well.
