SE-R Limited Slip Differential

Mar 20th, 2003, 10:49 PM

I autocross a `91 SE-R and would like to know if it's possible to kick the stock LSD lockup range (30-35%) up to 45-50% range, like the Nissan Motorsports unit. I understand that it's also a stock type unit. Also, what does the silicone in the viscous coupling do? Does this have anything to do with the percentage of lockup? Maybe the viscosity could be raised? I guess a `Quaffe' unit is the way to go, but I'd like to explore any possibilities with the stock LSD first. Any input would be appreciated. Thanks.

John

**morepower2** · Mar 21st, 2003, 12:22 AM

Quote:

Originally posted by zahn
I autocross a `91 SE-R and would like to know if it's possible to kick the stock LSD lockup range (30-35%) up to 45-50% range, like the Nissan Motorsports unit. I understand that it's also a stock type unit. Also, what does the silicone in the viscous coupling do? Does this have anything to do with the percentage of lockup? Maybe the viscosity could be raised? I guess a `Quaffe' unit is the way to go, but I'd like to explore any possibilities with the stock LSD first. Any input would be appreciated. Thanks.

John

Nismo makes a 1.5 way cltch type LSD that Nissan motorsports sells that works really well and is only a little more than the motorsports VLSD.

Mike

bahearn · Mar 21st, 2003, 10:49 AM

You cannot alter stock viscous dif. It uses a silicone-based fluid that drastically alters viscosity with temperature change. Two closely-space plates, one attached to each axle, spin in this fluid. When the two plates spin at different rates, the fluid experiences shear forces which heat the fluid which increases fluid viscosity which increases drag on the plates which causes the two plates (and attached axles) to try to equalize rotational rate.

Phantom Grip makes a spring-preload device to help the stock differential and is rather inexpensive.

The Quaiffe is not available except used at this time.

Mar 23rd, 2003, 09:43 PM

Thanks for the information on the lsd. I have another stupid question on the subject though. At 90,000+ miles I'm replacing the clutch and lightening the flywheel, and would at the same time like to at least bring the lsd back to the same tight feeling when it was new (I am the original owner). it's beginning to feel like an open diff. Could just replacing the stock viscous coupling with a new one do this. I am not familiar with the Phantom Grip device and will look into it. Thanks.

John

bahearn · Mar 24th, 2003, 04:43 PM

You would have to replace the entire diff. I don't know the cost but I'm sure it's not peanuts. Phantom Grip with green spring is probably your cheapest solution.