I searched, and couldn’t find the answer I’m satisfied with. I need to adjust the bands in my race only RMVB 727. I’ve read the specs are 72 in/lbs on both adjusters, back the rear one off 2.5 turns and the front anywhere from 2 to 4 turns. I’ve also read to snug them down until the driveshaft will barely turn by hand, and back 1/2 turn. What’s the correct answer for a car that only drag races? I have the rear band at the 2.5 turns right now, but I have to do some fiddling to get a torque wrench on the front band. Headers in the way and such.
Race 727 band adjustments
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Often impossible to get to front band adjustment with torque wrench
with Headers while in the race car. Just get the front band finger tight
(fairly snug) then back it off 1 1/2 turns (assume you have 5.0 lever).
Back band is not real critical 2 to 2 1/2 is fine..
Check it every 30 or 40 passes and change fluid then as well = Cheap Insurance.
That is exactly how I have done it for 60 years without any issues.
with Headers while in the race car. Just get the front band finger tight
(fairly snug) then back it off 1 1/2 turns (assume you have 5.0 lever).
Back band is not real critical 2 to 2 1/2 is fine..
Check it every 30 or 40 passes and change fluid then as well = Cheap Insurance.
That is exactly how I have done it for 60 years without any issues.
I neglected to do this the past couple seasons. Didn’t make many passes last year, and I didn’t think to do it when changing the fluid this spring. The 2-3 shift started getting lazy during the races in Boise. I bet the bands are about toast, but I was going to pull the trans to be redone this winter anyway. As long as it makes it through this coming weekend I’ll be good.
May be time for Clutch Plates as well.
Probably is. 5 seasons out of it so far. My last one made it 13 years, but it was behind less power and no brake.
Thank you John! This info is real timely as I'm about to change the filter and fluid in my race only 727. The only difference between mine and the OP is I have a trans brake. It's a Turbo Action reverse manual with brake. Do the same specs apply for the bands?
Mine also has a brake.
Sorry, bad assumption on my part!
Yes = Same Specs.
The Turbo Action is a great Valvebody
The Band and Clutch Plates do not overlap much
on the shift and clutch plates last much longer.
The transbrake is hard on the thrust bearing in the engine
particularly if you sit on it a long time. I suggest that ever
time you service the trans - you wiggle the engine damper
for play (.005 to.010 is normal ). When it gets .025 plus it
is time to replace the thrust and hope the crank is OK.
My son seems to wipe out the thrust every 3 or 4 years.
I never do = But I do not sit on it all day!
The Turbo Action is a great Valvebody
The Band and Clutch Plates do not overlap much
on the shift and clutch plates last much longer.
The transbrake is hard on the thrust bearing in the engine
particularly if you sit on it a long time. I suggest that ever
time you service the trans - you wiggle the engine damper
for play (.005 to.010 is normal ). When it gets .025 plus it
is time to replace the thrust and hope the crank is OK.
My son seems to wipe out the thrust every 3 or 4 years.
I never do = But I do not sit on it all day!
That’s more great information that I wasn’t aware of!
My procedure is I set the brake as soon as my stage light comes on and I don’t get on the throttle until my first amber lights. My launch rpm is set at 3K in the 2 step. I’ll definitely check the play on the crank damper. Thanks again John.
That’s how I do it too. I don’t get on the throttle until the top amber comes on, and launch at 3200.
The KD band adjustment is about timing, not application force. Timing of the 2-3 shift where the band disengages & the front clutch [ 3rd gear ] applies. There is sufficient travel of the KD servo to allow for KD band wear. You could experiment with the adjustment. If it is too too tight, you would have the band still applied when the front clutch applies; bind up. Adjustment too loose, band disengages too early before clutch applies & the rpms flare up during the gear shift.
It’s strange because mine doesn’t flare up. It just has a moment where it’s between shifts like a stock valve body. Feels like the 68rfe in my diesel shifting. It could be a VB problem as I’ve had trouble with it before. Coan made me a good converter, but their VBs suck.
I adopted a method that someone on here uses. I can't remember who it is. Shoot for about 5/16 clearance between the see I and levers. Seems to have worked very well for me. Either race or hot street.
Talked to my tranny builder. Snug the front band, and back off 1.5 turns. 1/4” space for the rear band. It’s still delayed between the 2-3 shift, but it’s been deadly consistent on the track. Just need to get through one more weekend after this 
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