What all is necessary to build a solid reliable 727 for mostly strip use. 700hp at approx. 3000 race weight.
I am thinking billet (steel or aluminum) drum
Low band apply Vb
Bolt in sprag.
Anything else??? What is a good rebuild kit? And what is a good manual to use as this will be a first time for me but I am capable. Also what brands are good and who on here is a dealer

I'm going to be watching this thread close. Great topic!

Jeff.

I think the important part is to replace the things that blow up. A&A 317-831-3066 would be my first call. They specialize in 727's and have all the good parts. Just don't get carried away, you can spend a fortune on 727 race parts.

Drum, sprag, valvebody, servo piston, and high flow drum support.
More power/weight... more parts.
I really like the trans case modification for external pressure adjustment.
Also would recommend moding the tailshaft housing for a speed sensor on the park gear. (thanks Dzu)

Depending on the RPM it will see, rollerizing the tailshaft is a good idea. Beyond that, good parts, I like billet servo parts, etc. Everyone has their own tricks, tweaks and preferred components. Deal with one of the guys who do them all day, use his parts and ask for his advice.

Call Dave at Pro trans,661-940-7400, for all good race your parts and ask him on which clearances to set your front and rear drum clutch plate clearances up at and so on
I've used his race trans and parts for many years with no problems
he is the best 727,904 and Pro flyte tranny builder and Hi Po race tranny parts maker in the world
A1,A&A and a lot of the other tranny builders buy many of their race only special parts form him

If is surprising how little you need to do to get one to live behind that horsepower level. I am at ~600 N/A and ~750 with nitrous.

I build my own and use a Transtar kit, Alto Eagle clutches and Kolene steels. I also used a Turbo Action manual valvebody and followed their recommendations. Removed the governor assembly for no reason other than it wasn't needed.

Stock drum, stock sprag, etc.

Mine gets driven A LOT and abused frequently. I've done a few street/no prep, stock radial style small town races leaving in 2nd gear, so it gets a workout!

A couple of points to be made: I put a Hayden cooler on the car in front of the radiator for it. Nothing kills a transmission faster than heat/burnt fluid! I also ALWAYS start my burnouts in 1st and shift to 2nd. The valvebody does have a low band apply.

Everyone I've seen that "upgrades" to the aluminum drums always have problems. Not for me, not for the way I use my car. Bolt in sprag is not needed, either, unless your case has issues and your stock sprag is loose.

Lots of gimmicks and uneeded parts sold in the 727 aftermarket IMO.

This is the last time you can decide on a clean sheet of paper whether any Chrysler is suitable w/r/t strength, weight, size, ratio choices, expense.
"mostly strip use": would O/D be useful? My DD has .705 O/D and 3.77:1 axle = 2.66:1 overall ratio, and wish I could slow the engine down even more but $$$.
Please note: IIRC 727 has a drum & band (70 year old design), TH has only clutches. inherently less dangerous.

Big cooler!

dont have this happen like it did to me

700hp is as piece of cake. Brake or no brake? No brake; old used turbo action VB. 4 plate front drum, aluminum one if you are scared of the factory piece. Early servo w/ inner and outer spring. 3.8 lever. Raybestos or Alto clutch frictions in the high drum, .012"-.015" per friction. You can run 5 frictions if you run the thin Altos. Not necesary at 700hp. Factory silver clutch frictions in the direct drum, .025"-.030". Solid red lined band. Deep 518 truck pan. Keep the end play tight. 3 pin planets are fine. This combo will go easy 500 passes before inspection. Running a brake? Add a steel front planet. If you're going to get a better low roller get the $200 dollar one from A &A, ATI, etc. You can fail even the better low roller.the standard bolt in are of no use unless your case is damaged. Don't be fooled. This combo works. My car runs the non brake set-up. 9.0@150 @ 3350 lbs. Currently 450 passes. Dizusters turbo car runs the trans brake set- up,9.52@142 @ 3750 lbs.
Doug

My 727 has a 5 pinion steel front planetary, billet steel drum, Non-LBA TA transbrake, bolt in sprag, and a deep pan. Been 8.90s at 150+ mph at nearly 3900 lbs. Been using this one since 2009.

I ran the same setup w/ no transbrake for 2 years (running 9.50s at 140 mph) before the stock drum blew up. Swept up the trans off the track and put it in a bucket that night.

A&A Super Sprag, Billet steel front drum, Cope race pump. My pump was trashed, and cost of max lug pump gears and modified support is about the same as the assembled pump. Went a bit overboard with the $499 Billet steel 4-pinion with roller thrust bearings, but the splines in the stock aluminum part were cracked and a few missing.
I also used the billet aluminum rear drum, and lightened sun shell.
Cope reverse manual VB with LBA (no trans brake, not permitted in the street class I run.)
Billet servos, Alto Red clutches and kolene steels. Case modified for rear vent, VB pressure adjustment, Front ears removed for trans shield, lube hole from cooler return to back of sprag.
Used stock shafts and governor support. Originally was going to use stock VB with TF-2 shift kit (forward pattern.)
4.2 Lever, billet strut and front band anchor. Kevlar bands.
Sort of like the Cope 727-5 ProRace II transmission, but with more upgrades.

I've never had an issue with stock servos. The rear has been known to crack occasionally. But unless you run LBA valve body it's only used in reverse, no extra load there. Foot braking over 800 hp the front planet splines may strip. Hurt 1 planet that was in a used race trans before I put 250 passes on it. Haven't hurt one since. Never has an issue with stock pump gears either. Current trans is on year 6, 550 passes. The billet steel drum is very heavy, nearly 10lbs. Better clutch and band life with the A&A aluminum drum. Band strut can be reinforced with a welded brace or you can spend $ on a zoomy piece. I feel the Red lined band works best. Do NOT use a Kevlar band on a aluminum drum. The stock rear band works fine. Most often I'll use the used piece if it looks good. Aluminum goodies, torinngtons, and lightened sun shell wI'll enhance performace, slightly. But longevtivity isn't changed.
Doug

I've heard not to use an aluminum drum for ocasional street use...is thos true ?

What are the drwbacks of using an aluminum drum ?

Dan
67 Barracuda..
470ci coming in.....

More band adjustments & the oil gets more contaminated.

Good to see most of the commenters have recommended aftermarket front drums.... after seeing one come apart in a friends car (stock), we’ve always run the billet piece. Personally I feel any car with slicks should consider this upgrade.

....since moving west I’ve consulted Pro Trans more than a few times. They’ve treated me well.

I've witnessed zero wear. Adjustment has stayed consistent for over 100 passes. It's an A&A drum, Better material? Don't know. Fluid looks fine as well. Using JR 1 synthetic fluid. It's gone easy 100 passes on fluid and both it and the filter looked usable at that time.
Doug

Ran an aluminum drum for years on a mostly strip some street Duster. Zero issues.

I think with the aluminum drum, you need to run the red lined band?

I used the steel drum as I planned to do more street driving, but I doubt I have put more than 3,000 Street miles on the car.

I used the Billet accumulator with the dual ring seals and built in blocker rod. Not needed, but I don't think it was very expensive? Rear Billet Servo with dual seals was a bear to install, needed several shims to get the seals past the retainer lock groove. It is likely overkill, but I liked the idea that it would be almost impossible for it to get cocked in the bore.
Front servo setup is the Sonnax super hold servo kit 22301B-01K.
https://www.sonnax.com/parts/1826-2nd-gear-super-hold-servo-kit

The MaxLug pump gears are overkill too for my setup.

The “max lug” gears are only overkill until you break the stock ones.... that was the last piece on the troublesome 727 in my car that failed leaving me sitting at the staging beams. Of course now that it’s all good and working great I’ve pulled it and am going 904.