LSD questions

[Guest Anonymous]

Anyone out there using an OEM LSD rear end, I would appreciate your input on these questions:

1. When using an OEM LSD unit, how do you know when the co-efficient of tire traction exceeds the break away torque of the diff clutches? Does it matter?

2. How tight can the clutches be packed to improve breakaway torque and has anyone got solid test data on the results?

3. Have you found anyone LSD lube to be better than another and why?

4. When using stock half shafts, do they need to me milled to align with the snap ring grooves in the carrier?

5. Does anyone build a shim for the ring to allow the use of stock ring & pinion assys?

If so, do they supply longer properly shouldered bolts as well?

Thanks in advance.

[Modern Motorsports Ltd]

Here's my mostly street/some lapping day input:

1. When using an OEM LSD unit, how do you know when the co-efficient of tire traction exceeds the break away torque of the diff clutches? Does it matter?

you'll start breaking your tires loose.....the better the traction the tighter you could tolerate your breakaway torque spec, so for general weather/traction the ~40(38?) NISMO spec seems good IMO

 

2. How tight can the clutches be packed to improve breakaway torque and has anyone got solid test data on the results?

 

Ron Tyler went up to just over a 100ft-lbs spec and then later backed off to ~70ish if I recall correctly (he was top gun in his autox class with his lt1t56240z. Contact me for his email.

 

3. Have you found anyone LSD lube to be better than another and why?

 

never compared them, local nissan dealers said they used GM POSI Additive and I've found it to be most commonly available and a million milllion chevies using it gave me some confidence as well. I add enough till my unit doesn't 'crab' at low speed crawling corners.

 

4. When using stock half shafts, do they need to me milled to align with the snap ring grooves in the carrier?

 

nope.

 

5. Does anyone build a shim for the ring to allow the use of stock ring & pinion assys?

If so, do they supply longer properly shouldered bolts as well?

 

I've never heard that the ring gear depth changed and made the spacer you speak of neccessary? 3.36's to 4.11's have been installed in R200 LSD's to my knowledge without such ring gear spacers (common in domestic posi's to use such spacers)