Found the Autostick weakest link, The hard way

[Ian-PT-GT]

After intense R&D with my car (48 1/4 Mile runs at 15 secconds), I have found the weakest link of the drivetrain (at least the first thing to go). The Torque converter![V]

It looks like with the Manual Trany, it is this area (clutch) that gets the greatest abuse.

It is being replaced this week, So I have to wait for more testing.

Ian

[Culprat]

Ian

What went wrong with it? the sprag,
shaft bearings,or turbine fins?
Sorry to hear it gave up the ghost.
Are you replacing it with a better unit,
or stock?

[PT-Dave]

Ian:

Can you give us some more specific times that you ran and what the boost was? I haven't been able to get back to the strip since last October when I was still stock. It was only an 1/8 mile strip, but my best 60-foot was 2.169 and best 1/8 was 9.52 @ 72.01 MPH. Pretty good for stock.

After getting a Tazzo VPC, I have been able to get a best 0-60 MPH of 6.98 seconds with the boost set at 15! Of course, this was on a normal city street, so traction was a major problem, as you know. The 60-foot was only 2.43 seconds, so it should do a lot better at a real track with VHT applied properly.

P.S. VHT = Very High Traction, a compound applied to the strip to enhance traction. It makes a world of difference!

[old head from phila.]

IAN: Sorry to hear about your breakdown,like to hear more what you did to cause it.Your breakage is our breakage.How about you other guys any problems.. Old Head.

[Ian-PT-GT]

are you saying that I am the cause of the damage!!!!
You are rightHEHEHEHE

Well after some time thinking of what could have been the reason for this damage, I have found that the cause is very simple: "Power Launch".

when I would get ready to run with another car, I would lock the brakes, start to accelerate the engine to charge the turbo and to load the torque converter for an extremly fun launch off the line (this is how I would launch my Camaros). It looks like this converter is not made for the horsepower that the engine can produce or it is at the borderline. It looks like any minor mod to the engine will make you have to forget about power launches and just floor it from idle and wait for the turbo to catch up with the engine.

It was explained to me by my old school racing teacher that: "The reason that the converter failed is because, the engine is trying to move the converter internals, like it should, and the brakes are to powerfull and are keeping the transmition internals stationary, creating a 200+ horses clash inside this little part. In the good o'l days, this was no problem because the power was going to the rear wheel were you had crappy drum brakes that could let the tires spin with no effort and let all those horses move allong the power train."

I was convinced with his teachings.

No more power launches for me.[B)]

BTW, although I was the Hallman Controller Pioneer, I have removed it from the car and now I am seeking a new controller path with a more controlable boost settings. I Think I have found the answer in electronics. Once I have finnished the research I will show you my findings.

Ian

[Ian-PT-GT]

In other tech issues:

I was runing the car with 10 PSI at first gear and 14 PSI with no drop in second and in thrird gear. I had mastered Bracket racing with a constant 15.4 at the 1/4 mile with an ET of 89.5 MPH. The incredible thing that this was with the engine completly stock! factory muffler, all silencers in! A K&N filter and the hallman controller set at a setting just enough that the Turbo would spool faster than factory setting and no spikes.

I know that the silencer issue could flare up in the forum but, I Tested with them both installed and removed and decided to keep them until my Cold Air Induction idea is completed (I have an idea for a CAI that I am keeping undercover until I am sure that I have made a real improvement from the completly stock configuration) or one that would satisfy me.

Ian

[Kirby]

The torque converter has always been the linchpin of automatics... has anyone found a Torque Converter Performance Shop that will build a PERFORMANCE unit?

The ricers have already crossed this bridge.(Shops specialize in Honda,Toyota,Mazda Performance Torque Converters).

[old head from phila.]

Kirby;There is a company near phila. called PAT'S CONVERTORS 610-237-6900. Ask for steve,tell you know bob.He has built convertors for me and freinds,And some of these cars have dynoed there engines at well over 1000 hp.,and use trans brakes,they run them up to 5000 rpm.on the brakes. Old Head(bob)

[Gary C]

talk to level 10 as well. they do *great* work on subarus, dsm's, anything automatic.
my GUESS is you roasted your converter due to extremely HIGH trans fluid temps and boiled the fluid.
Doing constant brake stands and launches under boost without a transmission cooler WILL do that.
I had a *built* '78 Trans Am with a 400 cube big block that *ATE* built automatic transmissions with manual valve bodies for lunch, THEN i finally realized my error and threw in a transmission cooler. *hundreds* of passes and a year later and it's still running the same as the day the rebuilt setup went in. After talking with the trans shop that does my rebuilds he was saying it's *VERY* common for cars with high HP/TQ that stall up the convertor off the line and launch to munch the converters and transmissions because they're boiling the fluid.
IF i had an autostick the FIRST mod i would do is a trans cooler. I put one on the tow vehicle after that munched a transmission towing the 30 foot enclosed trailer to the west coast, now 25,000 miles and MANY long distance tows with a fully loaded trailer later the transmission does *not* slip when we're towing the trailer fully loaded like it used to. so in *my* experiance any way, they DO work.

[MichaelDay]

While aggressive use might call for a larger transmission cooler, the Turbo AutoStick comes from the factory with an external air-to-oil transmission cooler. Since the turbo intercooler sits behind the lower grille (where the automatic transmission cooler is on the non-turbo models), the transmission cooler is mounted well above the intercooler in the turbo.

Certainly a transmission temperature gauge would be beneficial under severe use conditions and based on Ian's experience could be one of the more important gauges to add.