Units of measurement are tricky. Ideally, the best ones will convey not just a cold tally of some length or velocity or whatever, but also suggest a sort of visceral feel of the concept being measured. I think there’s room for improvement in the way we measure torque, and it has a lot to do with what bullies did to your nipples in the 3rd grade.
Let me explain a bit of what I mean by a visceral feel for a given unit of measurement. Horsepower evokes horses, an animal we have some sense of regarding power and speed. It’s not just an abstraction; we have a real world reference for it, even if it’s not literally the power of a single horse.
Same goes for units of weight — we’ve all lifted things, so we can imagine, in some way, just how heavy 500 pounds might feel, even if we never could lift that ourselves. We’ve all walked a mile or kilometer, we have a physical sense of what those lengths mean, and we understand the passing of time, which means we can, on some gut level, understand that 60 miles per hour is the same as one mile every minute, which gives us a pretty intimate understanding of what that speed actually means.
But not so much with torque. Even if we know, intellectually, that torque is the twisting force of an engine, it’s hard to convey that concept in a way that makes some sort of innate, physical sense to people with the common units: pound-feet, or newton-meters.
These measurements come from the nature of torque, which has dimension force times distance. Things can get pretty complex, but for the sake of most of what we do when we talk about the torque a car engine makes, we’re talking about twisting force. Now, pound-feet doesn’t really evoke anything we, as people can relate to regarding twisting force. But I can think of something that does:
The purple nurple.
A purple nurple (also known regionally as a titty twister) is likely the most intimate and visceral experience of torque that anyone ever has. Even now, decades since I received my last purple nurple applied out of hostility (my wife occasionally attempts to administer these, but I’m hoping that’s more out of a desire to hear me scream like a little girl as opposed to any real malice) I still have shudder-inducing memories of the pain.
A purple nurple is a pure exercise in the power of torque. A rotational force, delivered via a grippy hand, is applied directly to a point, which is surrounded by sensitive, delicate, nerve-riddled areola and nipple material. We all know the sting of a well-applied nurple — we feel it. So how can we translate this gut-level understanding of torque to how we quantify torque from car engines?
The answer? We need to quantify a purple nurple in established units, and then use that result as a base unit with which to measure torque.
To help me do this, I needed someone smarter than me, which, happily, we have — our own ex-automotive engineer David Tracy.
After some initial experimentation with torque wrenches, we decided the best way to measure a purple nurple would be to construct a synthetic nipple assembly that was designed to make easy nurple measurement possible.
Here’s what made up the nurple test rig: a knob, standing in for the nipple/areola assembly that has the nurplization acted upon it, a 10-inch rod, and a weight suspended by a cord. The assembly used as a fulcrum/pivot an old Jeep 4.0L motor mount bracket, because David put it together and Jeep motor mounts are the most common item in his home.
I wanted a test rig that most accurately reflected the motions used for a purple nurple: the nipple/areola complex gripped with the thumb and side of the forefinger, and the rotation force acted upon the nipple via both the wrist and full forearm.
To find an accurate sized knob to stand in for a nipple, research was done on the Jalopnik staff and certain willing spouses regarding nipple size. After explaining to HR that my asking, repeatedly, via a chatroom for everyone to measure their nipples was for science and not a form of harassment, I came up with these rough nipple size ranges, divided by gender:
• Males: 3/4” - 1.25”
• Females: 1”- 2.5”
(The female ones have been blurred out to reflect society’s unfair double-standards when it comes to nipple exposure.)
This measurement is the diameter of the nipple, measured on the horizontal axis, from areola edge to areola edge. With these numbers in mind, we settled on a 1.5” knob as a reasonable average between the two genders.
This appears to be fairly consistent with established research, though possibly a bit large for males. I think that’s okay, since an average purple nurple tends to take in a reasonable amount of skin around the areola, which makes me think a 1.5” grip-area makes sense.
A plastic knob of 1.5” (slightly tapered) and having a ridged outer surface was used, to roughly approximate the grip of a hand on breast skin, which actually provides very good grip with minimal slippage. Testing was done with a glove as well, and while this is not a perfect replication of the grip of a hand on a human nipple, it’s close enough for our purposes.
Using the synthetic nipple, tests were performed to determine how much mass, suspended at the end of the 10-inch rod (the moment arm), could be lifted by nipple-twisting force. Here’s what we found:
An object having a mass of 1.56 lbs was able to be lifted. This was the maximum amount able to be lifted, so it tells us the amount of force in our nurple. Since it was suspended 10 inches out (5/6 foot), we multiply 1.56 by 5/6 to get 1.3 lb-ft of torque.
Now, that’s not all the mass in the system; we need to add the mass of the rod as well. The rod is 3 ounces, which means each inch of rod weighs 1/4 of an ounce. The L-bend at the end of the rod (about 1”) we’ll treat as its own mass at the end of the rod, which is 1/4 ounce at 10” out.
We’ll add that mass (1/64 lbs, x 5/6 feet) to get 0.01 lb-ft extra of torque, which we’ll add to our 1.3 lb-ft, giving us 1.31 lb-ft of torque.
Okay, now, for the rest of the metal bar: it’s 10 inches, half of those inches are more than 5” from the fulcrum, and half closer than 5” from the fulcrum, so we can approximate this as a point load at midpoint.
At this point I should re-iterate that David did this math, because he’s smarter than me. I did figure out that this means that the mass of the bar is like a 2.5 ounce weight on a massless 5” bar, so there’s that. We add in 2.5 ounces/16 ounces per pound and multiply that by 5/12 inches per foot and we get 0.07 lb-ft.
We add that to our 1.31 lb-ft of torque for the bagged mass and little bend of rod, and get 1.38 lb-ft, which we’ll round up to 1.4 lb-ft of torque to make our lives easier by one decimal place.
So, we have our answer: a reasonably average sample of a purple nurple utilizes 1.4 lb-ft of torque, which gives us our unit:
1 Nurple = 1.4 lb-ft of torque.
So, armed with this new unit, let’s see how some notable cars stack up, nurple-wise! Oh, and we’ll use the abbreviation Nrp for Nurples.
2015 Dodge Challenger Hellcat: 707 HP/464.3 Nrp
2016 Mazda Miata: 155 HP/ 105.7 Nrp
2015 Bugatti Veyron 1200 HP/ 790 Nrp
1968 Mustang V8 230 HP/221.4 Nrp
1973 VW Beetle (mine, with 1600cc/twin carbs/headers): 60 HP/51.5 Nrp
(Note: initially, I made a math error, and multiplied by 1.4 instead of dividing.) Sure, the numbers go down in Nrp, but it’s still a much more relatable metric to work with, so I stand by it.
So, there you have it. Now, when I want to brag about how much torque my Beetle makes, instead of throwing around hard-to process numbers and units like “about 72 lb-ft,” I can just say:
“Ever had a purple nurple? It’s like fifty times that.”
And that should get the idea across pretty damn well, even to people who don’t know shit about cars. They’ll immediately know the general level of the forces involved, and the purple nurple reference will immediately let them know this is twisting power we’re talking about.
And then, finally, maybe they’ll respect me.
Nurples. The new unit of torque. Please help me make this a standard!
UPDATE: Fixed my stupid math error. Thanks for pointing it out!
Contact the author at firstname.lastname@example.org.