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.