Rebuilding a Nissan R200 Differential to be More Drift Happy with Z1 Motorsports!- Part 2: Tuning the Differential and Installing the Ring and Pinion

by Rathyna Gomer

Where we last left off, we had disassembled, cleaned and inspected all the parts of my differential. Now the fun and important stuff starts- setting up my limited slip differential to work better for the specific demands of drifting. We will also show how to set up a new ring and pinion gear set.

Read Part One Here!

Z1 Motorsport provided their R200 4.10 ring and pinion final drive gear set. This is a nice jump lower from the stock 3.50 ratio, which was bogging us down when trying to drift in 3rd gear. The 4.10 will put us in the fat part of our engine’s powerband. Hopefully, this means no more clutch kicking in third to keep the car in drift. This will allow us to easily run a more grippy set up so we can keep up in following and not be such an easy target when leading.

The ring and pinion gear is a highly stressed part in a drift car and the R200, although pretty strong, was not designed to take the torque of a large LS V8. To help improve the longevity of the ring and pinion and to make it run cooler, we first sent the gears out to a local aerospace shotpeener around the corner from our shop to get two-stage shotpeened.

Two-stage shotpeening means that the part is first hit with big shot for maximum surface compression, then a smaller sized shot to get in the gear tooth roots better. Shotpeening greatly increases the part’s fatigue strength or the number of stress cycles before failure.

After shotpeening, we WPC treated our gears. WPC treatment is a Japanese process that is very similar to shotpeening, except it uses a microscopic media shot at very high velocities. WPC gives a very fine, slippery, hard lubricious surface finish that reduces friction and operating temperature greatly. It also increases fatigue strength and enhances the shotpeening.

For more information on WPC, check this out!

First, we will start with setting up our diff. In the last article, we noted that our differential was a 1.5-way. This means that the diff locks fully in the drive direction and about half as much in the coast direction.

1.5-way diffs are generally better for road racing, as they tend to understeer less on turn in but are considered worse for drifting because they are less consistent in transitions, off and on the throttle and are harder to initiate a drift.

In the Pro drifting world, most cars either run a spool differential, which has no differential action or a very tightly locked limited slip. So to get around our diff being a 1.5-way, we are going to shim it very tightly to greatly increase the initial preload so it works more like a spool.

<p”>To get started, George first removes the four counter-sunk bolts, which hold the Kaaz limited slip differential together.</p”>

Mike made a special appearance and inspects the cone springs and clutch plates. He’s looking for signs of wear or lack of lubrication like the galling of the plates and if the cone spring is flattened. He also checked to ensure that the plates have enough stack height to be adequate for reassembly. The stack height measurement is used to ensure that the clutches have not worn excessively.