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727 Rebuild - Parts Preference

Mike67

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Im having a friend rebuild my trans as I still beleive that are controlled by black majic and a sprinkle of vodoo, that will be installed in my 67. Motor should be according to desktop 600hp/tq range will be a street/stoplight bruiser 99.9% of the time.
So my question is if I buy a VB with low band apply do I/ should I get a bolt in sprag?
Coan has a 16 roller 4 bolt super sprag ( which from my research has the most rollers for a 4 bolt) , every one else is 12-14 unless you upgrade to something Like Copes U!timate sprag. Coan seems like the most economical/ beneficial.
Valve bodies- is there any real noticiable difference in them? If so what are they? Looking for RevMan w/ low apply. Looking at Copes 2x or even 22x (144psi vs 155psi) how does that really affect shifts?
Should I lookat anything else? I would love to do the drum but tryint to keep this some what budget friendly..
Thanks
 
Do you want a manual reverse valve body or forward shift pattern.
What year transmission are you working with?
#1. If the transmission is a 1967, check the input spline count. Pre-1967 (and sometimes 1967) have 19-spline input shafts. 1967 and later have 24-spline input shafts. This will determine the torque converters you use. Most performance converters use the 24-spline input, but you might be able to get a custom built one with 19-spline?
#2. Front Drum / pump. Pre-1970 (or is it 1971) pumps have the support the earlier input shafts (19 and 24 spline) and use the front drum with the narrow pump bushing. The 1971-up the support takes a slightly larger diameter input shaft for the '71 up transmissions, and supports the front drum with the wide drum bushing. If you decide to use a billet front drum, I think all those billet drums use the '71 and up pump support.
The billet drums increase safety and hold 5 clutches too, but are not cheap.
#3. On the otherhand, I ran the '71 Charger for years at 12.5 @ 110 MPH, with the basic stock transmission, an aftermarket trans cooler, and a TF-2 shift kit.

Most clutch, steels, and gasket kits don't include the bushings. Usually I just replace the pump and output shaft bushings, and check the rest are not bad.
I don't worry about if the transmission had a 3 or 4 pinion planetary gear. The issue I see is with high HP cars, the aluminum splines will crack, and at that point, just install a steel spline gear.

I haven't used the Coan Super Sprag, only the A&A Ultimate sprag. What Cope sells is the A&A sprag.
I like the looks of the shoulder bolt setup that the Coan sprag uses.

I like using the rear vent conversion, just so if there is a trans leak at the bell housing, I know it is not from the pump vent.
 
Do you want a manual reverse valve body or forward shift pattern.
What year transmission are you working with?
#1. If the transmission is a 1967, check the input spline count. Pre-1967 (and sometimes 1967) have 19-spline input shafts. 1967 and later have 24-spline input shafts. This will determine the torque converters you use. Most performance converters use the 24-spline input, but you might be able to get a custom built one with 19-spline?
#2. Front Drum / pump. Pre-1970 (or is it 1971) pumps have the support the earlier input shafts (19 and 24 spline) and use the front drum with the narrow pump bushing. The 1971-up the support takes a slightly larger diameter input shaft for the '71 up transmissions, and supports the front drum with the wide drum bushing. If you decide to use a billet front drum, I think all those billet drums use the '71 and up pump support.
The billet drums increase safety and hold 5 clutches too, but are not cheap.
#3. On the otherhand, I ran the '71 Charger for years at 12.5 @ 110 MPH, with the basic stock transmission, an aftermarket trans cooler, and a TF-2 shift kit.

Most clutch, steels, and gasket kits don't include the bushings. Usually I just replace the pump and output shaft bushings, and check the rest are not bad.
I don't worry about if the transmission had a 3 or 4 pinion planetary gear. The issue I see is with high HP cars, the aluminum splines will crack, and at that point, just install a steel spline gear.

I haven't used the Coan Super Sprag, only the A&A Ultimate sprag. What Cope sells is the A&A sprag.
I like the looks of the shoulder bolt setup that the Coan sprag uses.

I like using the rear vent conversion, just so if there is a trans leak at the bell housing, I know it is not from the pump vent.

Sorry I didnt metntion the year, its actually a 72 model. I guess I want to be better safe than sorry. Again this will be a street car, the track is a pretty good distance for me to go to regularly...
I had spoken to the guys at A&A which were very helpful and they mentioned the Ultimate as being their design. I also spoke to John who was equally helpful.
I just dont know if my use would warrant the extra expenses. Thier complete transmissions are out of my budget, I did contemplate buying a Patriott Stage II (rated @600hp) with upgrades , said shipped to my shop would be $1800 or I could upgrade to the III (rated @ 800hp) for an additional $200.
The parts list I had came to about $1100
 
Built my own 727's for my bracket cars from '75 to '92. Many thousand runs, all stock hard parts (pumps, drums, planetaries, sprags), good front bands & clutches, aftermarket valve bodies. If you have 600 HP consider a billet front drum, sprag upgrade is a good idea, the '72 pump support & wide bushing drum is good, red front band & red front clutches. Decide if you want full auto shifting or a manual shift valve body. I have had 2 Cope 727's (only Pro built) I've ever used. Very happy with both, one was street manual shift, current is race manual shift. Both are great. I have built 2 727's for customers in the last 2 years using Cope components. Have always heard good things about A&A too. I think I had about $1000 in parts for the 2 Cope trans I built for customers w/o the sprag upgrade.
 
I'd also add to set all your clearances as close to minimum as possible - you can buy shims, different thickness washers and different thickness clutch steels to get the clearances where you want 'em.
 
I don't recall the exact clutch clearances, but he rear clutch is just for forward. It is not shifting other than to go from reverse to forward. Those clutches get set on the tight side, I think about 0.035" clearance if I recall. The front clutch is the one shifting from second to third gear, and you don't want to drag the clutches so they are set a bit looser. I think about 0.080" clearance, but the factory spec is really wide and depends on how many clutches are being used.
 
The rear clutch standard snap ring always seems to come out right, .030 - .035. The front pack varies more. I got the factory "selective fit" snap ring package in '73 with 6 - 8 various thicknesses, plus I keep all the one from my core transmissions. I set the front at right around .070 for the high HP or race trans & a little more .085 - .090 for lower power street applications.
 
Good quality rebuild parts. 4 clutches in the high rev drum. TF2 kit in the valve body. 518 repop deep pan , 3.8 lever. Rear clutch .025-.040", front clutch .015" per friction. At least 10 springs in the front clutch.That's all you need. I've built 6 of these in the last month.
Doug
 
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