TH400 build-pictures

Get a TH 350 pump bearing and pump bearing shims in .010,.015.020.

Knock the case bushing up slightly so the pump bearing and pump shim have something to pilot off of.

Remove and discard the 3 tab case washer and the 4 tab TW on the output shaft.

Usually the .015 shim sets the endplay right where it needs to be.

The pump shim and bearing go down where the 3 tab washer use to be.

Now you have rollerized the output shaft.



(This is just my opinion, Flame suit is on)

I would suggest leaving the intermediate snap ring where it is in the pix. The reason why:: If you put the openings of the snap ring opposite of the intermediate band anchor lug, you effectly turn the snap ring into 2 half moon shapes that don't have the lug engagement compared to the way you have it. (tomato/tamato)

This is for OTTO: The snap ring in the pix is a Torqueflight 8 rear clutch snap ring in either .088 or .106 variation. They are easier to source.

Whatever you do ,and this will sound totally stuipd and counter productive; Run a wave steel in the intermediate clutch pack. It will be easier on the snap ring, pressure plate,and case lugs and will have no ill effect on the durability of the clutch pack.

Mike.

thanks have the wave plate on the intermediate pack..
like the idea of the rollerized output shaft.
 
Do you have a picture of the complete piston cavity of the direct drum?

Metal sealing rings. How much line pressure are you planning to use?

HP level and torque converter stall? Need to know this to get a picture of intermediate sprag loading.

didn't get a picture of piston cavity.
I like to see line pressure about 165 to 175 at wot
hp level is between 600 -750
torque coverter 10" 3800 stall
 
turbo bit. That is an excellent way to stabilize the drum, and people would be wise to follow that example. But, believe it or not, there is a better way.
 
didn't get a picture of piston cavity.
I like to see line pressure about 165 to 175 at wot
hp level is between 600 -750
torque coverter 10" 3800 stall

That's a safe line. I run 200 in mine, but the shifts are pretty firm and I've been thinking of lowering it a tad bit to save on the int. snap ring lugs of the case.

I would hope your using a HD sprag on the int. And I'm sure you are. The OEM HD sprag arrangement should handle your specs. The lower line you're using will cushion the int. apply and will mean lower shock loading of the int. sprag. Less chance of a roll-over of the sprag. I didn't say no chance, because you are using a larger plate count in that pack now. If you are using the wavy in the int., you might want to periodically check that pack to see how that wavy is doing, as far as localized heat buildup.

The reason I asked about seeing the drum was because of the steel piston you're switching to. Early drums that used the sprag type one-way clutch setup had an air bleed checkball in the aluminum piston. If you switch to the steel piston, you must use a drum that has an air-bleed checkball in it. You can use a drum and a piston that have the air bleed checkball. But you must have one or the other or both. Not zero.
 
thanks have the wave plate on the intermediate pack..
like the idea of the rollerized output shaft.

The bearing at the output shaft is a mod that has been common in high performance 400s since I can remember. It is a good, dependable mod. You should do it.
 
That's a safe line. I run 200 in mine, but the shifts are pretty firm and I've been thinking of lowering it a tad bit to save on the int. snap ring lugs of the case.

Com'on Don, keep the pressure where it's at, use one of these This months special

And use a wave steel. Just kiddin on the wave steel:biggrin: .
 
thanks have the wave plate on the intermediate pack..
like the idea of the rollerized output shaft.

At the pressure your running, with the 4 or 5 clutches in the intermediate w/ wave steel, the pack will lock down so fast there won't be time for heat.

The rear bearing mod is one of the best "free" mods that can be done to a th400.:cool:
 
Com'on Don, keep the pressure where it's at, use one of these This months special

And use a wave steel. Just kiddin on the wave steel:biggrin: .

Wow! Now that is something to go to bed with! I guess everyone will be changing the snap ring gap location on the tapered snap ring too, with that neat part.

That was going to be one of my next projects. A good idea to work with. Thanks.
 
I knew you would like that Don, and the price is right as well. I love the technology and the thinking that goes into this stuff.
 
I knew you would like that Don, and the price is right as well. I love the technology and the thinking that goes into this stuff.

You know me well.

The only thing I don't like about the part is that the snap ring supporting region of the part should have been carried all the way across the part. Instead they used the area for marketing signage. The part is going to load that pin at an angle. I don't like that.

Patent Pending, Chris.

Ideas are flying wild. Thanks again, Mike.
 
that split bushing is a john kilgore designed product.it has been around for years.it does not stablize the drum.its purpose is to improve oiling to the intermediate sprag.check this out John Kilgore Racing Transmissions - Fastest Ford Mustang & Chevy Transmissions

I have to strongly disagree with you Chris. It does support the rear section of the drum. This prevents wobbling of the drum on the loose spline fit of the sun gear shaft. I also did not see where John is using it. I see an orange colored teflon ring in the last sealing ring groove. Yes, that last area does feed lube to the sprag. But, I can't see how that compares to the ATI setup.
 
John has the original design to his credit and gave ati permission to make it.I speak to john 1 to 2 x a week and have no reason to disbelieve his claim to the design.The id of the drum is larger than the od of the split bushing therefore it is impossible for it to aid in supporting the drum.if someone made it with a od of .001 smaller than the id of the drum it would aid but the narrow cross section of the bushing would make it marginal at that.there really isnt a support problem if new bushings are used in the center support and drive tube and this is the only time the area becomes a need for concern.some of us have (including myself0 overengineered this area of the trans.my attention to this area was to take the thrust off the rear of the trans by running the drum up against the center support.this reduction of thrust keeps an oil film on bearings when loaded beyond original capacity.the 400 thrusts all load to the rear of the trans.this is evident by the wear on associated thrust surfaces.supporting and centering the forward clutch hubs front end in the forward drum is where gains in centerlining parts can be made.it is an area to be explored only when evidence of a problem exists in that area beyond new bushings and good parts in operation.i think the real benefits in a th400 are in the valve body area.somewhere i have done alot of research.i still need to send you that steel shuttle valve don for the vbody i sent you.ill get it out tomorrow as i am anxious for test data.
 
That may be true that John developed it, but I didn't see that in the link you provided. Hence, my confusion. :confused:

Take the direct drum and mount it on the splines of a sun gear shaft. Now take the drum and notice how much wobble is possible, even with very good splines in the direct drum. The split bearing piece, even if it is .005" under the ID of the sealing ring bore of the direct drum, it will help stabilize the drum compared to not having it in there at all. If the split bearing OD is beyond the OD of the sealing ring lands of the center support at all, even if it's only .002", and I'm sure it's more than that, it has the potential of helping. Even so, there is a better way.

The forward clutch hub is supported and kept running centerline by the mainshaft and all the bushings associated with keeping the mainshaft at centerline. Hence, my recommendation to install fresh bushings and check fit on each rebuild. Even some new bushings are too loose after installation. Don't take it for granted that just because the bushing is new, it will give a good fit.

I've been holding off installing your VB because of that valve. I'm doing an upgrade to the car now, so after I get it dialed back in I'll be looking to try your VB out. Next few months, I would guess. Has the new valve been surface hardened?
 
Yes the valve is pre heat treated before it is machined.mike ridings gave me the material # and I ordered it .i think it is called 4310 preheat treated billet.The aluminum valves were like prototypes however i used a few.the 3rd gear circuit is the shortest on the planet.mike can chime in with the specs.have been using it quite a bit .i just sent the kilgore link so everyone could check his super lite.he is a true pioneer in the 400 realm.going out to dinner ill check back with you guys later.
 
Chris. Adding a needle thrust to support the front section, rather than letting the sun gear handle it, seems a bit overkill to me. If endplays are setup correctly, momentum acting on the OEM bearing will be managable. I'm sure that bearing sees much more load on it just from the load put on it due to the tooth angularity of the gearset. The idea is a neat deal, but I like keeping things as simple as possible so that when I have to change out parts during a PM, I'm not having to modify parts over again.

That would certainly come into play if you were forced to do a trackside repair. Unless you've brought your machine shop with you.
 
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