TH200 issue

when in low, it runs off the low roller clutch at all times in low gear. If it feels like your spinning and its not tires, it could be that roller clutch. The car will drive around and act normal when it is broken, under power is when it slips. this is a weak spot in a 200, same as a pro flite 904. they both use the same part. spinning the tires and breaking the rear end will shorten the life of this part rapidly...

[Alan Roehrich]

I was thinking that was the case Todd, thanks for verifying it for me.

That low roller clutch is relatively weak. I don't like to use it to launch a car. I prefer to have the clutches on.

I don't even like to launch a TH350 on the low roller sprag. I upgrade all of those to the late 700 R4 or 4L65E center support and roller clutch when people do that.

Most do it so they can run only 2-4 clutches in low, for less drag.

Always buy a new Borg Warner or Delco low roller sprag when building a TH200, and I like to take a shot blaster and some coarse steel shot to the inner race.

[Billy Nees]

Broken stator support.

[Alan Roehrich]

Billy, that should stop the converter from reaching full stall speed or flash stall speed. Normally. It's a common problem with big engines, but I don't see it too often with small blocks, especially in Stock.

[countrypuppy4865]

What Billy said had it happen car leaves terrible. Pull the tranny out and when you pull convertor out you will be able to see if it's broke.

[Alan Roehrich]

A stator shaft problem should show up on a data logger in a very obvious manner. The starting line RPM should be substantially lower, at least 2000 RPM lower than a previous "good pass". When the stator shaft spins, the converter will not flash, and it will not multiply torque.

With clutches, or the "sprag", RPM should be slightly higher, but driveshaft RPM should be lower.

[Chad Rhodes]

Originally Posted by Alan Roehrich

A stator shaft problem should show up on a data logger in a very obvious manner. The starting line RPM should be substantially lower, at least 2000 RPM lower than a previous "good pass". When the stator shaft spins, the converter will not flash, and it will not multiply torque.

With clutches, or the "sprag", RPM should be slightly higher, but driveshaft RPM should be lower.

The Converter flash seemed a little high as well now that I look at the data, it also ran within .3 mph of what it had all day. I'll have it out this week

[jim powers]

i agree with Billy, broken stator support, did the same thing back in 09 with my 305 k/sa camaro

[Gary Parker]

I have broken 2 stator supports. some are now changing them with a heavier one I believe adapting a turbo 350 one... that's what it sounds like to me

[Mark Yacavone]

Originally Posted by Alan Roehrich

Billy, that should stop the converter from reaching full stall speed or flash stall speed. Normally. It's a common problem with big engines, but I don't see it too often with small blocks, especially in Stock.

As stated, it won't stall up with stator free wheeling..It'll just act like a stock converter almost.
The low sprag is the weak spot alright.
You need to find out if the lo/rev clutches are on or off with your valve body.
If off ,and just the forward clutch on, I'm going with the sprag slipping..
Probably find broken springs and distortion on some kind...