Torque Converter Stall Explained!!

[Imp558]

.... oh not by me, I'm hoping one of you guys can. The 4Txx converter stall speed is measured by "K-Factor" which is actually superior to just saying it's stall speed as the stall speed varies from one engine to the next with different engines producing different amounts of torque. Having the K-Factor means that with the right math or chart we can figure what the converter stall speed is. The problem is ... I don't have the math, or chart. Could someone please post the information we need to gain this superpower of figuring stall speeds from K-Factors -vs- torque?

[mfewtrail]

http://www.themotorhood.com/themotorhood/2015/10/1/talking-the-torque-what-do-you-know-about-torque-converters

 

About 3/4 down the page, it gives some information on how K factor is determined.

[Imp558]

Thanks! That's it! I looked for it but could only find ways to determine K, not make use of it.

 

rpm = K*sqrt {torque}

 

So now we can tell that a W-Body JTFM converter with a K-Factor of 155 @ the stock L67's 280ft/lb of torque should be 2593 RPM stall. An H-Body JSFM converter with a K-Factor of 133 should be 2225 RPM stall.

My math skills suck so if this is wrong arguments may be directed to my calculator.

 

What's interesting is some later converters have a K of R115? I found some stuff regarding output torque divided by input torque something something. If the "R" isn't relevant for this (which it likely is) then a K=115 would be a really low stall of 1924 RPM.

[Imp558]

Running a dual pattern flywheel and a naturally aspirated FDHB converter with a K-Factor of 180 should be 3011 RPM stall, hmmm.

[Schurkey]

Never heard of "K-Factor" before today.

Thanks for that.