727 or 904?

crackedback said
The multi spring kit is more about RPM than HP. Unless you plan to spin the engine 6K plus, not likely with a stroker, get the lower dollar reverse wound spring from ATI. That'll save you $100

Plenty of real world examples of 904's living behind 500hp strokers for a long time. It's not the 70's anymore and people have learned how to make them live with additional clutches in a 4 clutch drums, stronger band pieces, etc.

Just about any decent valve body from ATI, T/A, transact and some others will work. A low band apply is really not a big requirement in a 904 becasue that's a crutch for blowing a sprag and trying to saving the front drum. Not an issue with a 904. People say the 904 will explode.... absolutely they will. BUT, you better be able to spin the engine ~9500+, because that's what it roughly takes for the stock 904 front drum to hit critical mass. I've NEVER seen a 904 explode like a 727 will... only takes about 5000-5500 RPM for a 727 to go BOOM! That's not hard to hit even for a stock BB or SB mopar. We had a 727 explode in a station wagon that was used to tow a boat! Oh the Fun with that.

An 8,000 rpm rev in a 904 with low gear gets the drum to 21,920 rpm which is kinda close. 8,000rpm multiplied by 2.74
Worst 727 drum explosion I,ve seen was not only the hole in the floor but the driver trying to get out of the car on one foot after the tranny oil ignited and the whole car went up in flames. He made it out ok with a injured foot. The car was toast.
John Cope explained somewhere on the forum that all trans brake valve bodies regardless of brand, apply the low band when the brake button is on. All of them.
The low band apply feature when discussed is pertaining to how long the band stays on after the button is released or whether it stays on until you pull second gear. The low band is applied to help the sprague withstand the torque of the motor on launch.
I paid extra to get "low band apply" on my recent purchase of a tranzact pro nitro brake even though Joe did not think I needed it because I feel it is more reliable to keep it on until the shift.
That is also how John Copes new brakes work as well. The trans would have engine braking all the time in 1st gear. My brake came with the line pressure set to 170 psi for a 904 setting according to tranzact.