Re: 727 band adjustment
[Re: mopar dave]
#2763960
04/14/20 06:57 PM
04/14/20 06:57 PM
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Joined: Dec 2013
Posts: 4,672 Wichita
GY3
master
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master
Joined: Dec 2013
Posts: 4,672
Wichita
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would like to pull the trans pan to take a peak and readjust bands. 727 specialist like bands on the tight side and most just use the old mopar performance spec. Just looking for opinions on how you guys do it and the spec you use. Thanks Tighten all the way in and then back off 2.5 turns.
'63 Dodge 330 11.19 @ 121 mph Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs. 10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.
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Re: 727 band adjustment
[Re: mopar dave]
#2763976
04/14/20 07:39 PM
04/14/20 07:39 PM
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Joined: Dec 2005
Posts: 11,551 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 11,551
Fulton County, PA
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4.2 lever? Like 2-2 1/4 turns out from 72 in.lb. If the pan is off, use a pry bar to pry the lever off of the pushrod and firmly apply the band. Measure the gap at the pushrod. Conversely, I think you could use air to apply the band and measure the difference between relaxed and applied at the pushrod. 5/16" is the number.
It's always interesting to use all of these alternate methods to adjust the thing. Then go back and mark the adjuster and go through it again using the 2 or 2 1/2 back from 72 in.lb. method, then compare where you end up.
Last edited by CMcAllister; 04/14/20 07:43 PM.
If the results don't match the theory, change the theory.
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Re: 727 band adjustment
[Re: 440Jim]
#2764012
04/14/20 10:03 PM
04/14/20 10:03 PM
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Joined: Dec 2005
Posts: 11,551 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 11,551
Fulton County, PA
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If you have the trans pan off, then I like to use a 5/16" allen wrench as a feeler gauge. Pull the lever by hand at the servo, and put the allen wrench between the servo pin and the lever. This eliminates the feel of tightening, then backing off a set amount for each lever ratio. Do a standard 2 or 2 1/2 turns off from 72inlb. Then measure it. Then you know exactly what the right adjustment is when the pan is on it.
If the results don't match the theory, change the theory.
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Re: 727 band adjustment
[Re: mopar dave]
#2764025
04/14/20 10:48 PM
04/14/20 10:48 PM
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Joined: Aug 2011
Posts: 2,857 Pattison Texas
CSK
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master
Joined: Aug 2011
Posts: 2,857
Pattison Texas
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Just found my notes from Keith over at 727 Specialists. 1.5 turns front bank and 1/4 turn rear. I have a cope VB. I believe cope follows the standard 2-2.5 turns. WOW this is very tight, might be the missing HP problem
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5
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Re: 727 band adjustment
[Re: mopar dave]
#2764048
04/14/20 11:59 PM
04/14/20 11:59 PM
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Joined: Jan 2003
Posts: 1,908 Nebraska
4406bbl
top fuel
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top fuel
Joined: Jan 2003
Posts: 1,908
Nebraska
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Just found my notes from Keith over at 727 Specialists. 1.5 turns front bank and 1/4 turn rear. I have a cope VB. I believe cope follows the standard 2-2.5 turns. I have always use the 5/16" spec, I would call and verify that 1/4 turn on the rear, maybe 2-1/4? I would think 1/4 would cause drag, wear, and a bunch of heat. If the pan has a bunch of crap in it I bet the rear band is worn.
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Re: 727 band adjustment
[Re: 4406bbl]
#2764133
04/15/20 09:14 AM
04/15/20 09:14 AM
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Joined: Mar 2006
Posts: 9,835 MI, usa
dvw
master
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master
Joined: Mar 2006
Posts: 9,835
MI, usa
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It is my feeling if the servo has enough travel the band "grip" will be the same. Grip/hold is based on band type, material, lever ratio, servo size. The apply timing may change with adjustment. So a couple of thoughts. No need to run the rear band tight. Its already applied in 1st if you run LBA. If not it's only used in reverse. Why create any extra drag? As far as the front band. Last year I fought a 1/2 shift timing issue. My car runs an old T/A stock based valve body. On the tach replay it showed over 1100rpm between the time the 1/2 shift light came on and the actual shift. Tried tightening the band various amounts, zero change. This trans (and others with this valve body) have always taken 500-700 rpm to complete the shift. The quicker the car accelerates the more rpm it takes. The time the servo clamps the band is basically a fixed value. So why now was it worse? After researching from some of the smartest Torqueflite guys I could find the initial issue was located. The trans is a cable shift (push button). The cable adjustment was slightly off. The manual valve was partially blocking the 2nd gear servo feed land. At this time the band was inspected (red material, aluminum drum) and looked like it just came out of the box. However it still took approximately 700 rpm to shift. The problem with that is the converter flashes to 6100rpm. The lowest you could set the shift light was 6200. Thus 6900-7000 shift. Wanted to try a lower shift rpm. Took the valve body to a very smart guy. He modified the feed passages for the 2nd gear servo feed and couple of other items. Now the shift rpm lag is 400-500. Wise advise I also received. If you loosen the band and it doesn't hurt itself or slow down its a positive move. This band has close to 500 passes and still looks new. My 2 cents. The 5/16" spec works well
Doug
Last edited by dvw; 04/15/20 11:18 AM.
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Re: 727 band adjustment
[Re: mopar dave]
#2764175
04/15/20 10:38 AM
04/15/20 10:38 AM
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Joined: Nov 2003
Posts: 36,040 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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Just found my notes from Keith over at 727 Specialists. 1.5 turns front bank and 1/4 turn rear. I have a cope VB. I believe cope follows the standard 2-2.5 turns. might that be 1/4"? iirc Kunkel had me adj one of the (904) bands to that clearance at the lever
live every 24 hour block of time like it's your last day on earth
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Re: 727 band adjustment
[Re: mopar dave]
#2764414
04/15/20 08:07 PM
04/15/20 08:07 PM
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Joined: Jan 2003
Posts: 1,908 Nebraska
4406bbl
top fuel
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top fuel
Joined: Jan 2003
Posts: 1,908
Nebraska
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Just dug out my 727 trans manual from CRT. Forgot I had that. Band adjustment is 2 1/4 turns with 4.2 lever and 2 turns on rear. Sounds perfect to me. It should end up close to that 5/16". If you just snug it with a short wrench you are good.
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