TH200 issue
 

Yesterday at Baton Rouge I had something very strange happen which cost me first round. I'm reasonably sure it's in the transmission, but I don't know enough about the Metric 200 to know the possible causes.

Both qualifying rounds were consistent with what the car should have run, and lights were consistent. 1st round I hit the same spot on the tree I had been hitting, and the car didn't react immediately, but when it did it felt like it spun. I was .178 and.2 off in 60'. Dad said the car did NOT spin the tires. I'm baffled at what could have caused it internally, but it seems like clutches. I don't even know if there is a set of clutches applied in 1st gear. Any ideas?

Re: TH200 issue
 

Depending upon the valve body, it could be leaving on the low clutches, or on the low sprag. In manual low, it should be on the clutches, if it has an auto 1-2 shift, and leaves in 2nd, it is leaving on the sprag.

By the way, I was at the machine gun shoot when you called, no way I could have heard you with around 30k rounds per minute going off.

Re: TH200 issue
 

It's an e-shift so it acts like a manual. It would have been on the clutches. Sounds like you had more fun than me yesterday. I'll give you a call this evening.

Re: TH200 issue
 

It may not actually work like a true manual. I honestly do not know, I've never fooled with those that much.

Re: 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...

Re: TH200 issue
 

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.

Re: TH200 issue
 

Broken stator support.

Re: TH200 issue
 

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.

Re: TH200 issue
 

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.

Re: TH200 issue
 

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.

Re: TH200 issue
 

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

Re: TH200 issue
 

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

Re: TH200 issue
 

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

Re: TH200 issue
 

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...

Re: TH200 issue
 

It's a turbo action e shift if anyone knows the answer before I call tomorrow.

Re: TH200 issue
 

If you have engine breaking in 1st gear, then the clutches are on.

Re: TH200 issue
 

Happened to our 200 yesterday at Bowling Green...

http://i434.photobucket.com/albums/q...ps518c2658.jpg

http://i434.photobucket.com/albums/q...ps4c435a8b.jpg

Re: TH200 issue
 

No engine braking in first.

If the stator support broke would it damage the converter ?

Re: TH200 issue
 

I don't know that answer either. Just to be safe I'm going to let ATI cut it open for a look on ours.

Re: TH200 issue
 

Then your clutches are not on. Very few use the clutches as they are faster without the clutches on.

Even if the converter doesn't get damaged, it will be full of debris. Needs to come apart either way.

Re: TH200 issue
 

Rich, is that paint or is your case broken? Hard to tell from the picture.

Re: TH200 issue
 

Okay, the sprag in the converter is what the stator shaft is locked to. So the shock of the stator shaft breaking is applied to the converter, and as such, the sprag. Is it broken now? Maybe. Is it possible that it may break later because of that? Yes.


To me, the best solution for this problem is to have a race pump built, with a TH stator as opposed to the metric stator, and upgrade the input shaft at the same time, to the larger TH spline. That gets you a better stator and a better input shaft, which will be less likely to fail this way later. It also allows you to use a TH style converter. Yes, it is more expensive. But broken parts cost money, and usually a race.

Re: TH200 issue
 

Yea, my thoughts as well. 7 passes on the converter, oh well.

Alan, you make a good point. I'm gonna give a lot of thought to it.

Re: TH200 issue
 

Good question...I had not noticed that. I'll let Arnett look at that when I hand if off. ;)

Re: TH200 issue
 

The metric input shaft is rarely an issue. If anything, it's the connection of the shaft to the forward drum that fails.

There are pumps that have an upgraded metric stator support installed to solve this problem. Like a 200-4R, a stator upgrade goes a long way to making a durable long-life pump.

Re: TH200 issue
 

I'm late with a reply, but I broke a stator support one year and I could hold the throttle to the floor with out the 2step and the engine would only go to 2000. I thought the engine was broken. No tq mutiplication to the rear wheels at all. Also when my stator support broke it trashed the converter, and I ended up throwing it in the garbage. Trans and converter in one shot.

I would never run a metric without a turbo input and a billet stator support. The whole pump assmembly can be bought from Leo at Remac ready to install. Then you have interchangeable converters between the backup and the front line trans.