At full throttle do you guys have your converter lock in 1st,2nd,and 3rd or just 3rd at full throttle???
trans is a 4L60E
converter is a Yank SS3600

 

I would never lock a TCC in any gear except 3rd or 4th gear. The problem is that it is very abusive on a transmissions internal parts and also the converter when the trans shifts with the tcc clutch applied. I also do not recommend locking any single disk converter under WOT. I have seen and heard of plenty of them coming apart on a chassis dyno when doing this. If you have the need to lock the TCC up under WOT I would strongly suggest using a multi disk converter. Only do it in 3rd to allow you to get down the track without having to shift into OD. Most guy's rig up a manual switch that still allows the computer to do it's job under normal driving. If you run out of track and need 4th, then it is time for a gear swap. Vince

 

I was just wondering for HP loss when the verter is unlocked.We have my dads locking in 3rd only at full throttle a little after the car shifts into 3rd.Then 4th locks normally for the highway.

 

The TCC was never designed to carry the weight of the vehicle at WOT.

If the car is experiencing some ort of power loos, then locking the TCC is only going to mask the problem and destroy the converter. But hey, if replacing converters and freshening up trannis is not a big deal then go for it! Lots of our customers do this and expect to replace their converter, or at least repair it several times a season.

If however replacing the converter and freshening up the traany is not a good idea in your dad's case... I would suggest more HP at the crankshaft rather than locking the converter. Locking the converter is "cheating" the system so to speak. No big deal though if you plan to be in the tranny often but the idea is to match the torque converters staqll speed with the engines hp /torque curves.

Hope that helps.

g

 

As stated above locking the converter at WOT is not a good idea it will damage the converter clutch unless its a multi disk type which most are not, Further more if the converter is a good match to the car you may while gaining HP on the dyno lose times on the track due to the loss of torque multiplication, Many people I have noted who have tried this have actually gone slower down the track.

 

Do you offer a multi disk converter?

 

No presently we do not however have had experince wih locals who have used the precision industries

 

So do the stock converters not lock in 3rd at full throttle???I had no idea that everyone with after market converters and tunes had there verter not lock up.Hmm learn something new everyday.I guess we need to change the tune and have it unlocked in the first 3 gears all together.

 

The stock converter (with factory programming) does not lock up even in 4th under WOT, unless you lift slightly. The TCC lining is just way to "fragile" (12" diameter x 1" wide x 1/16" thick) for such abuse. As stated, the only converters that should be considered for locking up at WOT are aftermarket multi-disc units.

 

Even if it -could- take the abuse (you would want Yank's
opinion on that) you are liable not to see a benefit, let alone
one that outweighs the wear & tear or risks. If the converter
is still multiplying torque, and you are not trapping after the
3-4 upshift, there is no performance benefit. You gain more
by being on HP peak and slipping, than by being lower RPM
and hard locked, if the converter is any kind of efficient.

I would upload a log showing this, if the attachment thingy
weren't busted again. I think I posted it already (early May
is the log date). Acceleration "lays over" visibly when the
converter locks up, indicating I lost multiplication (compare
acceleration at same engine RPM, locked & unlocked).

If Yank backs the notion of WOT lockup then you can do your
own experiments but I expect you'll see the same result (no
gain, possible pain). The only guys who need to do this are
the ones who are geared right on the edge of upshift at the
trap, where holding RPM down beats a last-100-ft upshift to
4th and there's no cushion left in the rev limiter. Which one
you wanna break for that last 0.1 sec? Motor or trans?

But even guys who find it helped for that, don't seem to
stay with the method; they fix the hardware (gearing) to
follow the motor's / platform's progress.

 

Your regular swipes at Frank and his classy responses has guaranteed that I will be purchasing a Performabuilt tranny. Apparently you feel you are the only company in the U.S. that knows anything at all about transmissions. I'm sure you do build a hell of a tranny but I'm betting my cash that performabuilt does too.


P.S. Frank, you guys should sell Vigilante converters. I'm buying one of those from P.I.

 

Thanks guys for all of the info, we learned something new. Already returned the converter to unlocked in 3rd at WOT via HP tuners. Thanks again for the info.