Hi there I encountered some strangely rated LSD's (Subaru but it doesn't matter does it?) Maybe you could help me decode the numbers and convert those.

Usually on UK sites diffs are rated in Nm. Lets' say havy duty centre LSD for Escos is either 50Nm or 80Nm. But I found some that are rated e.g. 20kgf-m/100rpm, 4kgf-m/100rpm, or "9 kgfm breakaway torque" on some torsen-style front diff. What those mean? Thx for input

 

its just a differant means of measuring the force, what your missing on your '50nm and 80nm' is that its rated per second iirc, i.e

50nm/s not just 50 newtons.

and the break torque is just what the diff will start to turn at against a fixed load. i.e 9 kgfm will be the point at which the diff will turn against itself.

hth

mark

 

Yes I understand that it schould be nm/s, but how to decode this strange kgf-m/s ? How does it convert to Nm/s?


I must say I don't understand

You mean it's a point at which other wheel starts to get more torque then the one that has less ressistance or what? I didn't get this part :-/

 

have a look throught the net , theres force converters available that you just input the figures, then you may have to divide/multiply the time factor.

and yes your almost there with the break torque, its i.e just say we are talking 2wd, and the diff is set to a figure of 70ft/lb, if i lift one wheel off the floor, place the car in gear ( so the pinion cant turn) then apply a torque wrench to the hub nut, i should see 70ft/lb on the wrench setting before the wheel(hub nut) will turn, this is the pre-load of the diff.

does that help ?

 

I will look. I though that you might know the full vertion of that abreviation.


I understand that but this figure stood next to helical type LSD, so something Torsen/ATB-like. I know there are hybrid diffs that employ both speed sensing and torque sensing mechanisms - does that mean it's this kind of diff?
And this brake torque would be the figure next to all those diffs that have Nm/s or this kgf-m/s figures next to them as this is how we measure locking action normally, isn't it? Or Am I missing something still?