[LMSRACER]

1) Coan Hard Coat Anodized Aluminum Direct Drum with the Pro-Mod Sprag Assembly.
2) Coan "Billet Aluminum" Direct Clutch Apply Piston (w/o Checkball) designed for a Six Clutch, Clutch Pack.
3) Coan, Four or Five Clutch, Intermediate Clutch Pack designed for use with their Pro Mod Sprag. (Four should get it done.)
4) Coan "Billet Aluminum" Intermediate Pressure Plate Support for the Case.

Other than that, the rest of the Internal Components can take a lot of abuse. The weak link, at your intended Horsepower Level, is the Intermediate Sprag and Intermediate Clutch.

Mix and Match Parts if you like, but I seriously do not recommend that.
Coan makes Transmission Jewelry. I DO NOT work for them, but I do use their parts without regret. I can NOT say that about some of the others.

BTW, If you're looking for detailed instructions with their parts, well, it ain't gonna' happen.

Larry S.

[GTOGEORGE]

Originally Posted by Scott Roberts

Sounds like u were a hammer smasher for 43 years...

I had my moments but basically!



GTO George

[Scott Roberts]

Originally Posted by LMSRACER

1) Coan Hard Coat Anodized Aluminum Direct Drum with the Pro-Mod Sprag Assembly.
2) Coan "Billet Aluminum" Direct Clutch Apply Piston (w/o Checkball) designed for a Six Clutch, Clutch Pack.
3) Coan, Four or Five Clutch, Intermediate Clutch Pack designed for use with their Pro Mod Sprag. (Four should get it done.)
4) Coan "Billet Aluminum" Intermediate Pressure Plate Support for the Case.

Other than that, the rest of the Internal Components can take a lot of abuse. The weak link, at your intended Horsepower Level, is the Intermediate Sprag and Intermediate Clutch.

Mix and Match Parts if you like, but I seriously do not recommend that.
Coan makes Transmission Jewelry. I DO NOT work for them, but I do use their parts without regret. I can NOT say that about some of the others.

BTW, If you're looking for detailed instructions with their parts, well, it ain't gonna' happen.

Larry S.

I am a big fan of Coan.. great service and great products..

[Scott Roberts]

Originally Posted by GTOGEORGE

I had my moments but basically!



GTO George

I call all millwrights hammer smashers...I'm an automation guy... i do a lot of keyboard smashing... I'm sure you were good at what you did George..

[GTOGEORGE]

I got no problem with “hammer smashers” hell I worked in a steel mill.....hot steel, big overhead cranes.....dangerous place to work.....life goes on, I’m out! As for being good at what i did......I think so but it depends who you talked to. LOL!
I also had my time as a Boss and also a keyboard jockey at the mill.

GTO George

[Scott Roberts]

Originally Posted by GTOGEORGE

I got no problem with “hammer smashers” hell I worked in a steel mill.....hot steel, big overhead cranes.....dangerous place to work.....life goes on, I’m out! As for being good at what i did......I think so but it depends who you talked to. LOL!
I also had my time as a Boss and also a keyboard jockey at the mill.

GTO George

I work at an aluminum extrusion and casting plant... not as hot as steel mill but 1000deg. Is hot enough for me.. and very dangerous aswell..
Fortunately, I spend a lot of time in the a/c on a computer...
Also like to point out that dragncar said engineers are smart...lol I have trained several..
Back to the trans discussion...
.

[Half-Inch Stud]

@LMSracer; aside from details and assembly, do have you an opinion on ATI parts vs Coan parts?

[LMSRACER]

Originally Posted by Half-Inch Stud

@LMSracer; aside from details and assembly, do have you an opinion on ATI parts vs Coan parts?

The ATI Aluminum Direct Drum is not Hard Coat Anodized. Because of this I've seen accelerated wear inside the Drum where the Clutch Steels contact the Drum Surface. I've also found accelerated wear in the Splines where the Sun Shaft is engaged for the same reason.

For High End Builds, Coan also offers a Radial Ball Bearing that presses into their Modified Center Support and their Direct Drum has a Machined Lip that then fits into the I.D. of the Radial Bearing. This configuration positively supports the rear of the Direct Drum. It far exceeds the ATI Brass Bushing Configuration that they offer for their Center Support to do the same job.

Let me say that I do use ATI Parts for Turbo 400s and Powerglides. I like their Front Pumps for example, but for the Parts that I previously listed in my original post I would go with Coan.

Larry S.

[Half-Inch Stud]

MY opinion; If there are any aluminum splines offered on "Performance parts", just say no.

[RA462]

May I ask at what point the 36 element Pro-Mod sprag is required?

I have been using the stock direct drum with a 34 element sprag for years. I have been making as high as 829 HP and 650 TQ the last couple of years shifting at around 7200 RPM. This year I have been making a few changes to increase the HP. Ironically I just ordered a Transmission Specialties (hard coated) aluminum direct drum with the 34 element sprag on Friday. The plan is to also install the aluminum forward drum with the oversize 40 spline input shaft while I'm in there. Myself do my own transmission work and I am a former machinist and currently working as an engineer.

[JSPONT]

Originally Posted by RA462

May I ask at what point the 36 element Pro-Mod sprag is required?

I have been using the stock direct drum with a 34 element sprag for years. I have been making as high as 829 HP and 650 TQ the last couple of years shifting at around 7200 RPM. This year I have been making a few changes to increase the HP. Ironically I just ordered a Transmission Specialties (hard coated) aluminum direct drum with the 34 element sprag on Friday. The plan is to also install the aluminum forward drum with the oversize 40 spline input shaft while I'm in there. Myself do my own transmission work and I am a former machinist and currently working as an engineer.

My third time out with my new th 400 and a 34 element sprag. this is what happened. Heavy car little for torque than you with drag radials. have a 300 m larger splined input shaft, billet hub, fti billet brake, 2 extra steel and cutches in the drums. I just ordered a 36 element sprag, what the tranny guy said to do in the 1st place. I know about 6 people who broke a 34 element sprag, especially on a street car where there is tire spin.

[GTOGEORGE]

Originally Posted by RA462

May I ask at what point the 36 element Pro-Mod sprag is required?

I have been using the stock direct drum with a 34 element sprag for years. I have been making as high as 829 HP and 650 TQ the last couple of years shifting at around 7200 RPM. This year I have been making a few changes to increase the HP. Ironically I just ordered a Transmission Specialties (hard coated) aluminum direct drum with the 34 element sprag on Friday. The plan is to also install the aluminum forward drum with the oversize 40 spline input shaft while I'm in there. Myself do my own transmission work and I am a former machinist and currently working as an engineer.

I had a warmed over 400 turbo in my car running 8.90's-8.70's with little problems, it wasnt until I started running 8.50's and quicker that I really started to break my trans......finally i got fed up and wrote a check to Rossler for something that wouldn't break.


GTO George

[Dragncar]

Originally Posted by Scott Roberts

As a millwright, can u answer this simple question..
I have a sled let's say with a m100x3 adjustment nut on it.. if I want to move that sled precisely 1/4", how many times do I turn the adjustment nut?
I don't know chit about transmissions... just a question for fun...

I can not say I have ever used a adjustment nut for anything like a "sled" in my experience.
You must be talking about steel or aluminum "mills".
Around here its all about wood. Sawmills. There are no sleds. I do a lot a fabrication, build gear motor bases, chipper repair, conveyors, wood hogs, head rig carriages . Things like that. Air and hydraulic cylinder work and their valves.
I always wondered what it would be like working in a steel mill. I know a millwright is a food processing plant. Lots of different types of millwrights.
Even know a welder on the Golden Gate Bridge. A lady, 50$+ a hour. Good work, and not much of it too. State benefits. She has a great gig.

[Dragncar]

Originally Posted by RA462

May I ask at what point the 36 element Pro-Mod sprag is required?

I have been using the stock direct drum with a 34 element sprag for years. I have been making as high as 829 HP and 650 TQ the last couple of years shifting at around 7200 RPM. This year I have been making a few changes to increase the HP. Ironically I just ordered a Transmission Specialties (hard coated) aluminum direct drum with the 34 element sprag on Friday. The plan is to also install the aluminum forward drum with the oversize 40 spline input shaft while I'm in there. Myself do my own transmission work and I am a former machinist and currently working as an engineer.

Thumb up !!!

[Dragncar]

Originally Posted by LMSRACER

1) Coan Hard Coat Anodized Aluminum Direct Drum with the Pro-Mod Sprag Assembly.
2) Coan "Billet Aluminum" Direct Clutch Apply Piston (w/o Checkball) designed for a Six Clutch, Clutch Pack.
3) Coan, Four or Five Clutch, Intermediate Clutch Pack designed for use with their Pro Mod Sprag. (Four should get it done.)
4) Coan "Billet Aluminum" Intermediate Pressure Plate Support for the Case.

Other than that, the rest of the Internal Components can take a lot of abuse. The weak link, at your intended Horsepower Level, is the Intermediate Sprag and Intermediate Clutch.

Mix and Match Parts if you like, but I seriously do not recommend that.
Coan makes Transmission Jewelry. I DO NOT work for them, but I do use their parts without regret. I can NOT say that about some of the others.

BTW, If you're looking for detailed instructions with their parts, well, it ain't gonna' happen.

Larry S.

Thanks, this is exactly the kind of thing I was after. Things we can do our-self to make it more reliable.

[taff2]

Up to around 850-900 hp, I find that most TH400 sprags break because of the lack of accumulator function/ no wave plate in the int. pack or worn out bushes that allow the drums to rotate out of concentricity, this coupled with high line pressure is a killer.
I've run stock 8 roller 'sprags' to 7000 rpm without a problem, but in a low hp (575hp) light car. In fact all stock parts.
My current approx 960 hp turbo combo uses all stock internal parts, albeit modified, but again its a 2800lb car on the footbrake. I've just changed to a transbrake so will see how these parts last- I use the trans as a test bed for budget mods to use for my customers , the types who can't afford a $5000 Coan .

[Dragncar]

Thanks taff. Any more info would be greatly appreciated. If I can Build a tranny for 2000 $, maybe 3000$ that gets close to the reliability of the 5K versions, that is what I am after.
Then let people know how it was done.

[johnta1]

Try a search on Jake shoe here?
(for do-it-yourself)

Or Jake Shoe

Think it's been a few years since he was on here.
He sells parts or complete trannys I believe.

[LMSRACER]

Pro Release Trans-Brake Valve Bodies do not use Accumulators of any kind to soften the shifts. Therefore utilizing a 1-2 Accumulator to ease the stress on the Intermediate Sprag is not an option.

A Steel Direct Drum Assembly with 6 Clutches Weighs in around 14 pounds. It spins at 84% of Engine RPM in the Opposite Direction of Engine Rotation in First Gear. During the 1-2 Shift the Intermediate Clutch Applies and Grabs the Outer Race of the Intermediate Sprag and Locks it to the Transmission Case. The Sprag then has to stop the Direct Drum from Rotating. Without any type of Accumulator, this happens very abruptly. This is why the Sprag Breaks.......

Reducing the Rotating Weight of the Direct Drum Assembly by going to Billet Aluminum helps greatly. In addition, by going to the Pro Mod 36 Element Sprag, which is considerably larger than the 34 Element Sprag, the chances of breaking the Sprag becomes very unlikely.

When the 2-3 Shift is made the Direct Drum Assy. now goes from a Stop to Engine RPM Immediately. The Reduced Weight of the Aluminum Drum Assembly Accelerates much more readily and therefore accomplishes two things. First it eases the Stress on the Direct Clutches and Second it Helps to Accelerate the Car More Quickly.

These are the reasons why I recommended these components. They are high dollar, but, these are the high dollar components that will give the OP the best bang for his buck. Much of the rest of the Internals just need quality rebuild components with the correct selection of clutch materials and clearances to get the job done.

BTW, just a little FYI....
A Sprag has Elements, BUT, these are also known as Lugs or Segments.

Larry S.

[Half-Inch Stud]

Originally Posted by Half-Inch Stud

MY opinion; If there are any aluminum splines offered on "Performance parts", just say no.

REMINDER ^^^^^^^

Curious if any of those hubs recommended with AL splines?