In an earlier post, I described losing reverse in my newly built 727 while running it in on jack stands! The trans builder promised that he could build an automatic shifting 727 that would hold up behind my 600 ft.lb. torque HEMI. When he stopped by to examine the pan, he declared the trans "terminal".
I talked to two builders who are recommended on this site. Both insisted on a manual valve body.
How much power have you guys been able to push through an auto shifting 727 before failure? This will be a 99% street driven car. Full weight 66' Coronet convertable.

I'd t hink it would be other parts of the trans that go 1st. 727's are very strong and can handle a ton of power if built right. I wouldn't put a stock unit behind a 650hp motor but w/ a few changes it can easily h andle those numbers. My trans was done by Performace Automatic. I re-used my Turbo Action MVB in there street/strip unit. No problems.

The modern version of the 727 is the 47re and 48 re in the diesel trucks.

There are many of then running daily with with more torque than you have!
mine will make over 900 ft lbs. I have 140,000 miles on this trans--47re--- and it shifts better now than when it was new.

All the valve body does is tell it 'when' to shift. It has nothing to do with how much power is going thru said trans.
High HP +/or Torque applications should require some internal modifications such as a bolt in rear sprag, better lube circuits, better clutches, etc etc.

MY advice, you can't get any better than a John Cope unit.
And this one is behind a 484" Hemi with just over 500 HP and about 550 ft lbs of torque.
Even though I know how to build transmissions, but should I need somethign like this again, He'll get my call.

i once owned,and worked at my trans shop here in town for 10 yrs..1982-1992..i enjoy building and tricking my 727's,even now,but if i had a serious car,and or a big hp cust. car,and wanted the best,and latest tech/parts, i would call john ,at CRT'S,and have it done right,but have him build a trans for the application,hp level/usage,ect,and not your budget. he is a great guy. mike

I did talk to John and I agree, he was very helpful. He did hesitate to put an auto shifting valve body in the trans due to the torque and weight.
What power level have you run with an auto shifting 727?

Full automatic shift. So far so good.

What John from CRT and Rick from A & A both were concerned about, was line pressure with an auto shifting valve body at this TORQUE level.

If I understand correctly, you can adjust the pressure at full throttle to wide open psi in the valve body. However, when you are at PART throttle, and DON'T have full pressure that seems to be the concern.

So the question remains, "how much power have any of you put on an auto shifting 727 without failure"?

Thanks so much! THAT is experiance that I have been looking for! To make 120 mph trap speed with over 4,100lb. takes a strong engine! How long have you been driving this setup with no issues? Did you buy a valve body from anyone in particular, or have your trans built by that shop?

Does your trans have manual or auto valve body?

Who did your trans?

John. 2000 miles and about 30 passes at the track, and probably another 30 full throttle 1-2 shifts.

Rick did the one before and it probably had 200 passes, and 15,000 miles, but I was making less power then.

I'm not sure why part throttle pressure would matter

I was running my #4,150 Charger in the High 11's with a near stock 727, and the Trans-go TF-2 shift kit in the stock valve body. When I took it apart the clutches still looked good, but the front (low) gear set was shot. The aluminum splines in the gear were cracked and some fell out when I pulled it off the output shaft. A new billet steel 4-pinion roller bearing set from Cope was $500.
I beefed up the new trans with a billet steel front drum and piston for safety and to add an additional clutch, $535. This required a beveled rear drum, so I got the billet aluminum rear drum $225. Figured may as well get the lightened sun shell, Max lug pump gears, and A&A Ultra sprag - $165 / $105 / $200.
Anyhow, by the time I got done with all the extra parts like servos, bands, Alto red eagle clutches and kolene steels, thrust washers, rear vent, deep trans pan, billet struts and ancor, 4.2:1 lever, Ultimate 9" converter, etc I have about $3,500+ into a 727 transmission.

Thanks for the info. My local trans guy was pretty convincing on the Trans Go Shift kit with second option as well.

It is interesting that both Rick and John built you an auto shifter with no problem. Maybie I should have held back when they asked if I had dynoed the engine? Do I read right, did John build this last trans for you?

Would you mind sharing some more info on your car? It looks like you set yours up with a "stock" look, as I have done. I notice the stock wheel/hubcaps. Are you running stock wheel wells? I am and they won't accept a large tire. I am running CalTracs. What suspension/tire combo did you use to get 4150 lb. to mid 11s? I am also running a 3.54 gear. I am shure that 4.10 would help your et. I am more interested in driving/enjoying my car for hours at a time on the street than seconds on the track.

Suspension....a snubber and battery in the trunk. I'm probably the last guy you want suspension info from. Stock wheel wells. The car does not have a good 60 ft, but is the way I want it overall. Here is a little more info.

http://508charger.yolasite.com/