The MSP LSD is not a torsen... yet the window sticker says torsen? Bwah?

DistantTea

Member
:
Mazdaspeed... of DOOM!
I was always under the impression that we had a torsen LSD unit... then I read two different articles... one of which is in the May Grassroots Motorsports and they go into detail about what the Conical Ring Tochigi Fuji Sangyo differential really is... Its not a torsen, its not even close. But another member got his window sticker and the damn thing says we have a torsen... What the hell is going on. Now I have a 2003 and he has a 2003.x... they didn't change the diff in the different releases did they?

From GRM: "They are similar in operation to a clutch pack differential, except that instead of a clutch pack, these units use cone clutches similar to those used in the synchronization of a manual transmission" and goes on to describe mechanics "As torque is applied from the ring gear to the differential case, the pinions generate spreading load as the tires resist turning, forcing the conical side gears (which are splined to the axles) into friction surfaces on the inside of the case, limiting the slip side to side. In this case, the torque is biased to the side that has the most resistance - aka grip."

They even mention our car specificly in that article. "However, Mazda has chosen to fit a TFS Super LSD unit specifically tailored for front-drive service to the MazdaSpeed Protege and has clearly developed the unit to work properly in that application due to its small size and lower torque-bias ratio"

Thats not a torsen unit... thats not even close. Now TFS does make a tosen unit, but its not whats in our car. I'm very conefused.

Thats a pretty big mistake for a window sticker.
 
Just one of another many lies that Mazda fed us about this car...I say we make them put in whats on the window sticker or we sue!

How bout that one MAzda!
Matt!
 
hehe, i swear you guys cry about everything lmao. if you dont like it, make it better your self
 
Minus said:
hehe, i swear you guys cry about everything lmao. if you dont like it, make it better your self
but is right for manufacturesr to lie to the consumers
 
hey, us ZX2 guys are trying to get you LSD's to fit, at least you have one stop bitching. You wanna make it worse? Mazda knew the tranny's were crap since 98 and still put them in your MSP's
 
I believe it is actually a Origami Sanyo Fujitsu LSD that was installing in the MSP's.. Look for threads from JDMSam and others for details.
 
torsen is a heavily misused term from what I've been learning. Torsen is actually a brand, but most people refer to it as a "type" of LSD. In the type sense the MSP is a torsen of sorts I believe... as it is torque sensing, it doesn't require actual slippage from my understanding to generate the torque bias (whereas for example a viscous coupling LSD does). A Quaife is also referred to often as a Torsen differential, it is torque sensing, but it is not a torsen it is actually an ATB (auto torque biasing) differential.

So what I'm getting at is that if I'm correct on the MSP LSD being torque sensing as I belive it is, then they could call it a torsen TYPE differential it is NOT a Torsen (R) differential.
 
TurfBurn said:
torsen is a heavily misused term from what I've been learning. Torsen is actually a brand, but most people refer to it as a "type" of LSD. In the type sense the MSP is a torsen of sorts I believe... as it is torque sensing, it doesn't require actual slippage from my understanding to generate the torque bias (whereas for example a viscous coupling LSD does). A Quaife is also referred to often as a Torsen differential, it is torque sensing, but it is not a torsen it is actually an ATB (auto torque biasing) differential.

So what I'm getting at is that if I'm correct on the MSP LSD being torque sensing as I belive it is, then they could call it a torsen TYPE differential it is NOT a Torsen (R) differential.
(crazy)

info overload...
 
Last edited:
Well that is the best I know as of to date... I could be inaccurate in some place on there, but I'm pretty sure it's ok, but anyone with more knowledge please feel free to correct me!

Thanks,

Steve
 
here is more info on the MSP diff:

Limited-slip differential

The Super LSD (limited-slip differential) from Tochigi Fuji Sangyo KK includes a core clutch developed to work well with the strut suspension found in front-wheel-drive vehicles. The unit also works well in the front axle of four-wheel-drive off-road vehicles. Compared to other torque-sensing LSDs, the Super LSD has a lower torque bias ratio (1.5-2.0), which fits well with front suspension systems. Production costs are lower because of similarities to open differentials, and the device can be lubricated with standard differential fluid or ATF. The system can easily replace open differentials because it uses many of the same components and features identical installation points. The device provides good handling and control as well as a cost reduction.

from:
http://www.sae.org/automag/techawards/2002/page5.htm

which has been posted before... but confirms what i remembered about torque sensing... quaife's website talks about their ATB differential... and I think there is a website for Torsen as well... and then howstuffworks.com goes in to detail on a few of the types of differentials.
 
Direct from Mazda USA:

Torque Sensing Limited-Slip Differential - Tochigi Fuji Sangyo
<TABLE cellSpacing=0 cellPadding=0 width=575 border=0><TBODY><TR class=bgcolor13><TD><TABLE cellSpacing=0 cellPadding=0 width=553 border=0><TBODY><TR class=bgcolor02 vAlign=top><TD colSpan=3>
With this much power in a front-wheel-drive vehicle, maintaining traction can be a challenge. Our engineers anticipated this problem and added a Tochigi-Fuji Sangyo KK Super torque-sensing limited-slip differential to the MAZDASPEED Proteg. Without it, the vehicle would transfer power to the wheel with the least traction, resulting in wheelspin. With the limited-slip differential, the MAZDASPEED Proteg transfers power to the wheel with the most traction, helping you achieve greater grip and maintaining power, especially while cornering.

</TD><TD>
spacer.gif
</TD></TR><TR class=bgcolor02><TD>
spacer.gif
</TD><TD>
spacer.gif
</TD><TD>
spacer.gif
</TD><TD>
spacer.gif
</TD><TD>
spacer.gif
</TD></TR></TBODY></TABLE></TD><TD>
spacer.gif
</TD></TR><TR class=bgcolor13><TD colSpan=3>
spacer.gif
</TD></TR></TBODY></TABLE>
 
Torsen types use a number of helical gears for function, with the angle and number of teeth on those gears determining torque bias. The conical ring uses a conical clutch centered around the pinions, torque bias being determined by spring load against those pinions.

Quaife makes a dozen different differntials... they make a torsen for sure, but they make a racing spec clutch type, which is similar to the popular Kaaz unit. The MSP LSD is NOT torsen... the only gear found in it is the ring gear.

Now is Mazda using torsen to be short for Torque Sensing? Because Torsen is a type of LSD that is entirely different than the TFS Super LSD (Conical Ring type).

Personally? The conical ring type is a better differential than the torsen unit, like that found on the integra type r. A true torsen unit requires for constant traction of some sort on both drive wheels... if one wheel goes up in the air the unit dosn't transfer. But still, whats up with that damn window sticker? Torsen my ass.
 
TurfBurn said:
here is more info on the MSP diff:

Limited-slip differential

The Super LSD (limited-slip differential) from Tochigi Fuji Sangyo KK includes a core clutch developed to work well with the strut suspension found in front-wheel-drive vehicles. The unit also works well in the front axle of four-wheel-drive off-road vehicles. Compared to other torque-sensing LSDs, the Super LSD has a lower torque bias ratio (1.5-2.0), which fits well with front suspension systems. Production costs are lower because of similarities to open differentials, and the device can be lubricated with standard differential fluid or ATF. The system can easily replace open differentials because it uses many of the same components and features identical installation points. The device provides good handling and control as well as a cost reduction.

from:
http://www.sae.org/automag/techawards/2002/page5.htm

which has been posted before... but confirms what i remembered about torque sensing... quaife's website talks about their ATB differential... and I think there is a website for Torsen as well... and then howstuffworks.com goes in to detail on a few of the types of differentials.
Yeah I posted that, and I was wrong. That is NOT the LSD in our car according to GRM. Ours is a conical ring. Maybe GRM is wrong? I dunno. What, has anyone grenaded their LSD and opened it up? Whats in there, a cone clutch or a bunch of gears?
 

New Threads

Back