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727 builders #2645644
04/16/19 08:53 AM
04/16/19 08:53 AM
Joined: Feb 2013
Posts: 84
La.USA
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rick4106 Offline OP
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rick4106  Offline OP
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La.USA
Red or blue clutch plates? Smooth or serated plates on direct? Clutch pack clearance and band adjustments?

Re: 727 builders [Re: rick4106] #2645659
04/16/19 09:35 AM
04/16/19 09:35 AM
Joined: Nov 2015
Posts: 870
Missouri
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jwb123 Offline
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Missouri
I have had good luck with the red clutches. Never used the blue ones much. If the unit is built right, don't think it makes much difference, bottom line is they are all basically paper glued to a metal disc, they will just not tolerate slippage. The clutch pack clearance depends on how many discs in the drum and how the drum is used. The general rule is .010 per clutch, so a 4 clutch drum should have .040 clearance. On the 727 the rear clutch, or I call it the input drum is applied in all forward gears so it can get by with a little less clearance in a pinch, and I use smooth discs because I want all the holding power I can get. On the forward or direct drum I want serrated discs because this clutch has to engage and disengage when shifting. the serrations allow oil to control this application better. Main issue is on a 727 the band has to release and then the direct clutch has to apply to get 3rd gear. So even in a perfect transmission you always have a short time of overlap, or both friction elements applied at the same time. The key is to make the overlap time as short as possible. band lever ratio, clutch plate clearance, kind of drum, and band adjustment, all have to be juggled to make this happen perfect. When I went from a stock style drum to an aluminum drum with a stainless sleeve I wound up with a slightly tighter band adjustment to make it work right. The reduction in rotating mass of the drum affected the shift timing as well. So one size does not fit all on your question. On the 2nd gear band adjustment I do it the Gil Younger transgo way, tighten the band until the drum will not move and then back off adjustment about 1/2 turn or until I get free rotation. On the reverse band I just use the factory spec as it only works in reverse. If you have a band apply valve body, use the specs for the modifications you make in the servo, so it releases clean.

Re: 727 builders [Re: jwb123] #2645695
04/16/19 12:27 PM
04/16/19 12:27 PM
Joined: Dec 2005
Posts: 11,408
Fulton County, PA
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CMcAllister Offline
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Fulton County, PA
Blue plates are more money, but are also a better choice for higher horsepower applications, along with Kolene steels.

Smooths with a high static material, if you're not using the blues, in the rear (forward) clutch. Grooved or checkered in the high (direct) gear. The front and rear clutch packs have very different jobs to do.

The forward clutch gets set up tight. As tight as .025 or .030. It's applied in all forward gears so a little drag is not an issue. Direct gets .010 to .012 per disc. Give or take, depending on if it has a brake, needs to have a minimum of drag (class car), etc.

Initially, I will run the front band adjustment with the pan off and then check the servo rod to lever clearance. Using a screwdriver or bar to lift the lever and apply the band, check the clearance between the lever and the rod. Make note of the adjustment needed to achieve 5/16" there with whatever band/lever combination you are using. I've also juggled spring loads in the front servo to fine tune the shift. Even adding or subtracting shims/spacers under the center spring makes a difference. A data recorder helps here as opposed to just listening for the flare. A touch of flare on the shift (no overlap) is the fastest way down the track.

I don't do a ton of them, but these are things I've picked up along the way. YMMV.


If the results don't match the theory, change the theory.
Re: 727 builders [Re: CMcAllister] #2645708
04/16/19 01:34 PM
04/16/19 01:34 PM
Joined: Mar 2006
Posts: 9,791
MI, usa
dvw Offline
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I've run standard Raybestoes tan frictions at 700hp#3400#. Over 700 passes w/o an issue. Current build has Kolenes and Altos in the front clutch .012-.015 vlearance per friction . Rear clutch has standard silver stock frictions. Rear clutch .025-.030 total clearance. This trans has gone over 400 passes on these parts currently. 900hp@3350#. Band adjustment varies with KD lever ratio. 5/16" is a good starting point. I like the red solid KD band.
Doug

Re: 727 builders [Re: dvw] #2645737
04/16/19 03:23 PM
04/16/19 03:23 PM
Joined: Feb 2013
Posts: 84
La.USA
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rick4106 Offline OP
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This is a A & A Ultimate aluminum drum transmission out of a car he bought. Has 4 serated altos in direct that the fiber was starting to come off. Was thiking of putting the 5 thin instead of the 4 thick with the kolene steels. This trans was originally built in 08 or 09 and has sat for 8 years. Car ran 5.35 best in 1/8 leaving off foot brake at 2500 rpm. Mainly seal job and plates. Does everyone use tefon rings on input and stator.

Re: 727 builders [Re: rick4106] #2645775
04/16/19 06:43 PM
04/16/19 06:43 PM
Joined: Mar 2006
Posts: 9,791
MI, usa
dvw Offline
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dvw  Offline
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MI, usa
Originally Posted by rick4106
This is a A & A Ultimate aluminum drum transmission out of a car he bought. Has 4 serated altos in direct that the fiber was starting to come off. Was thiking of putting the 5 thin instead of the 4 thick with the kolene steels. This trans was originally built in 08 or 09 and has sat for 8 years. Car ran 5.35 best in 1/8 leaving off foot brake at 2500 rpm. Mainly seal job and plates. Does everyone use tefon rings on input and stator.


Mine runs 5 thin smooth Alto with a combo of thick/thin Kolenes in an A&A aluminum drum. Red hard band and drum look like new. Rick Allison told me do NOT use Teflon rings with the aluminum drum.
Doug

Re: 727 builders [Re: dvw] #2645809
04/16/19 08:11 PM
04/16/19 08:11 PM
Joined: Apr 2005
Posts: 935
Deland, Florida
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biff426 Offline
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Joined: Apr 2005
Posts: 935
Deland, Florida
On the recommendation of A&A as well as a couple other high end trans builders I put Raybestos GPZ clutches in the trans I'm building for my current project. I should have it in the car in a few weeks and will report the performance.

Re: 727 builders [Re: biff426] #2657055
05/19/19 10:02 PM
05/19/19 10:02 PM
Joined: Feb 2013
Posts: 84
La.USA
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rick4106 Offline OP
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La.USA
From A&A 0-.010 end play on rollerized setup. .015-.020 endplay on input shaft.







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