BB 727 Hi/Po vs Standard trans. difference?

[RT68440]

And for the record, this trans isn't going to be raced or beat to hell. It's going behind a 440 with 10.5:1 compression, Stealth heads, Comp hydraulic .488/.491 cam, Edelbrock CH4B intake, 2400 stall and 3.23 gears. Like the motor, I want to make sure that the transmission can be built a little stronger than the factory did and I want to be sure that I'm starting out with a trans that is up to the task.

 

[monaco66coupe]

correct, new stuff, same housing.

 

[oldbee]

RT68440 I could be wrong but a standard rebuild will use "standard" parts. The "good stuff" will be extra and has to be specified. Maybe dvw or Miller will chime in, haven't done one since the 70's myself.

 

[monaco66coupe]

And for the record, this trans isn't going to be raced or beat to hell. It's going behind a 440 with 10.5:1 compression, Stealth heads, Comp hydraulic .488/.491 cam, Edelbrock CH4B intake, 2400 stall and 3.23 gears. Like the motor, I want to make sure that the transmission can be built a little stronger than the factory did and I want to be sure that I'm starting out with a trans that is up to the task.

the transmission you have is good just as stock rebuild, just a few mods to beef it up further and you are good to go!

 

[RT68440]

Yes, I definitely want to use better parts. I was just saying that today's "standard" parts are probably equivalent if not better than the "upgraded" parts that they used when these cars were new. But I would absolutely use the better parts by today's standards just for peace of mind...

 

[383man]

You don't need all the trick stuff. Even Rabestoes tan frictions, stock servos and 3 pin planets will all last for year's in a 10.50 car. The Hemi stuff is old scool heavy and expensive. Besides a good valve body or valve body kit your good to go. 4 friction front clutch, set at .060", early KD servo, 3.8 lever. If you're going to spend any money on aftermarket parts put a good billet front drum and race style sprages from Cope, A&A, TCI. This car runs stock 3 pin planet carriers, shafts, servos, pump gears. 1.240/9.04@148. On year 3 w/o rebuild.
Doug

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Doug is right. The 727 I built in my 63 is more stock then you would think. And being I worked at a Dodge dealer for 24 years and did trans work I have a few extra Mopar 727 parts around my garage. I use all stock clutches and steels in my 727 in my 63 street/strip car. The only major changes I did was the Turbo Action reverse manual valve body and a bolt in sprag (overrunning clutch) along with a Luppo Dynamic 9.5 converter. I knew I was only going to race my car a little as I only get to race about once a year as its mostly all street miles and I dont street race the car. In fact I drive it pretty easy most of the time and just wind it out a little now and then. I keep my racing to the track. But my 727 has been in my 63 since 2006 and it still works like new and can be driven to the track and run 10.70's and 80's. Most mild Mopar street cars dont need a $4000 dollar 727. They just need a good built mostly stock 727 with a few mods as Doug said. If your building a 9 second race car then sure you will update to some stronger parts. Heck I even have run the 3 disc front clutch in a low 11 second street car that has been fine for many years. But its a street car thats not raced every weekend and mostly just driven normal. Ron

 

[383man]

You need to get your tranny guy to teach you how to build one. They are not hard to do but knowing the tricks is what makes them good......after all, he's not going to be here forever. Man, I hope I'm still able to get out of bed let alone build a trans when I'm 80 lol

The 727 is not a real hard trans to build. If your mechanically inclined a little you can handle it once you know what to do. To be honest being I have been an auto tech all my life the thing is there are some who learn how to put a trans together but dont learn just how it works. Yet they go call themselfs a trans tech but when something dont work right with the trans they have no idea what to do. The best I thing anyone who wants to work on auto trans is learn how they work and what happens inside them. Then go learn how to take them apart and build them. Believe me it will help you understand what you are doing so much more and make it easier when you understand what the parts do you are removing or replacing and fixing. I found that in all the automotive work I do. Once I understand how it works it makes it much easier to work on them since you know how it works and why you are doing what you are doing to the trans or whatever it is. Good luck to you. Ron

 

[AR67GTX]

Unless you happen to have a good transmission parts house in town, I found everything I needed at MAKCO, TSR Racing and Cobra Transmission. I just rebuilt mine for the first time and it's running good. TSR Racing was owned by the writer of the 727 Rebuilding Book by Carl Munroe before his passing. You can get pretty much everything you read about in his book from them.

 

[miller]

All spot on.
The key thing to keep in mind is, the 727 is a good basic design to begin with...makes for a good start. By no means any expert, though I've built a good handful.
Their like anything else, use good parts, build it 'right', and it will do it's job!
Even more these days, many more options on parts...so, you pick your poison, and go from there. (It does NOT take thousands of dollars, to make these things work good!)