4L80E build

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Originally Posted by P10crew
Another snag that I failed to see prior.
In the msrk instruction it says to use 3 oem th 400 intermediate plates to reduce shock loading of the intermediate sprag.
Is this the part he is referencing?
In my steel kit there is (4) .078 steels or is he instructing to use (3) th 400 frictions. Totally lost as to what I'm supposed to use and how many because if it's the frictions there is steels for 4. Please give me some direction as to the intermediate stack up. Thanks



He's referring to Waved Intermediate Friction Plates for a TH400. Not the Steels.
If you were to run the heaviest PR Spring......Waved Intermediate Frictions would be a good idea!
*Set the clearance to .040", Run the factory Wave against the Piston, Keep the Feed Orifice under .093" & use the Sonnax PR Spring......You'll be just fine with 4 Flat high energy frictions.
 
Just so I fully understand what your laying out here...
Knowing that I want firm but not objectionable shifts you are recommending everything after * correct?
 
Originally Posted by P10crew
Just so I fully understand what your laying out here...
Knowing that I want firm but not objectionable shifts you are recommending everything after * correct?


That is correct.....The Orange PR Spring included in the MSRK kit is higher in Rate than the Sonnax PR Spring included in the 4L80E-LB1 kit.
 
If I remember correctly ck has a choice of 2 pr springs. So he is saying that if I run the heaviest pr spring it is advisable to run (3) 400 waved frictions? When you do that do you run the 80e wave against the piston and 80e steels ?

The wave must give some cushion to the intermediate clutch right?
 
And by us running .040 and small feed oriface. By virtue of small feed oriface and a tight stack it will be pseudo coushioned correct? Or put another way it will be just lazy enough to act like it's coushioned?
 
The 4L80E Intermediate wave is pretty good at cushioning.....It has many "crest's" compared to most wave plates. It's made of spring steel so it retains it's memory for life. And they don't break like the Forward & Direct waves!

The Purple CK spring is very similar to the Sonnax spring that's also Purple
wink.gif


Running a 4L80E Intermediate Piston requires the use of 4L80E Wave! If you omit the wave....The first Steel will not rest directly on the piston, It will rest on the Case Lugs! Thus throwing your actual clutch clearance off, You'll think you have .040" when you actually have much more (Piston Travel).

When I run a TH400 3-Friction set-up in a 4L80E......I run a TH400 Intermediate Piston as well. It has a Higher Installed Height.
*Then a TH400/TH425 .100" Wave.....That are impossible to find without harvesting them out of cores.
*TH400 Friction directly against the Steel Wave.
*Flat .100" steel.
*TH400 Friction
*Flat .100" steel.
*TH400 Friction.
*TH400 Pressure Plate.
I ONLY run this type set-up on Competition, Fixed Line pressure, Trans Brake 4L80E's as you must delete the 2nd Accumulator.
 
Originally Posted by P10crew
Got itðŸ‘
what do I adjust to achieve .040? First



Check that the thick Intermediate Pressure Plate I sent you fits your case......(Case Lugs). If it doesn't, I'll send another one or you can modify it to fit using your original as a template.

Stack the Intermediate clutch like this.....
Wave
Steel
Friction
Steel
Friction
Steel
Friction
Friction
Steel
Original 4L80E Pressure Plate
CK Snap Ring.

Apply shop air to the tool you made, This will apply & seat the clutch., Disconnect the air.
Using Feeler Gauges inserted between the Pressure Plate & the Steel directly beneath it....Check & record the clearance.

Report the clearance back to me.
 
Intermediate clearance
2 stacks of feeler gauges that measure .0795 with the caliper.
[Linked Image]

Made this little tool to come up with a faster method.
.082 @90 psi @ positions 12, 3 and 5 .
.0855 @ clocking position 9. Position 9 has no case lug/ snap ring support. These tests were with wet frictions stacked up per your direction with 80E pressure plate. The 400 plate major OD is identical but the minor OD is .080 too large to fit through the case lugs. This unit has the 99 up .275 plate. I see the 98 down plate is .366. If those fit the case lugs one could machine a relief for the snap ring. Or maybe the 400 stuff stacks up better.
 
By the way... who ever came up with the idea to use the sprag race and air to align the frictions gets 🺠a growler.
 
One more question the direct wave that they sent me has very shallow wave according to wit. I set it on my mill table and there is definitely a slight wave to it. Should the wave be deep enough to be noticeable with the naked eye?
 
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The easiest solution to this, Given your talents & equipment......Purchase a TH400 Intermediate Piston, Machine the counterbore larger to accept the 4L80E Wave plate, Then machine the Work Surface to achieve the desired clearance.

The TH400 piston is @ .065" taller than a Late 4L80E piston.

Here's one on E-Bay & it's in South Dakota.....HERE
As rare as these are becoming, It's a decent price. Not all TH400's had Aluminum Pistons, At least half of all production throughout the years had Stamped Steel pistons.
 
Originally Posted by P10crew
Any ideas on this direct wave?


Call WIT, Unfortunately.....This is becoming quite common for Raybestos to mislabel products for older units.

Alto part# 031701
GM part# 8623113
 
Originally Posted by P10crew
Thank ya sir!
Looks like you worked in the rain today


Nope....Cleaning up my work area from some coolant spatter. Coolant "Tracks" everywhere & I hate it!! The lift I use to pull cabs is technically outside....But has a really good awning covering it.

I'm going to build something very similar in the front of my new shop as I love to work outside in the breeze. I've been cooped up in dark-hot shops most of my life, So it's kind of refreshing!
 
Piston showed up and got it faced.
My sales ladie at WIT turned the thicker direct wave issue over to her buyer and haven't heard back.
I see on monster that they have a direct wave for a 400/3l80 that is .060 thick. What does the clearance need to be in the direct clutch? Thanks!
 
Originally Posted by P10crew
Piston showed up and got it faced.
My sales ladie at WIT turned the thicker direct wave issue over to her buyer and haven't heard back.
I see on monster that they have a direct wave for a 400/3l80 that is .060 thick. What does the clearance need to be in the direct clutch? Thanks!


.010"-.012" per Friction.....Do Not run it tighter than that!! The Direct Frictions Overrun in 1st & 2nd gears.
 
[Linked Image]

Wit / raybestos sent me the spec on the 34127A direct wave with direction on how to measure it. The one they sent me measures .008 wave and according to raybestos is .068 thick material. The stock one that was in it has .0365 wave and is .042 thick. Does this sound like the correct wave?

The as left intermediate clearance ..... nailed it! .040 stack of feeler gauges on one side.041 goes on the other stack. I'm calling it .0405 . dial indicator shows .0425- .043 in the 12,3,6 clocking positions @90 psi.
👊
 
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