Converting to 350Z Axles…

While in the USA doing work on 240SX MAYHEM, we found that both the right and left axles were completely shot. The inner CV boots were missing and the tripod housings that contain the bearings have been left without lubrication and are open to the elements. Not good.

Repair? Replace with used 240SX axles (6-bolt style)? Buy new ones (yes, you can get new ones)? No to all. It’s time to modernize.

The 240SX inner CV joint is a tripod design with three roller bearings. This design is fine, but starts to show weakness when suspension modifications (lowering, “stretched” axles w/o spacers) are incorporated and with added torque. Since 240SX MAYHEM is not a resto-mod candidate, we aren’t going to look at using the tripod design anymore.

Tripod Design
Tripod Design

Enter the Rzeppa CV joint…

rzeppa1

The Rzeppa was designed by Alfred Hans Rzeppa for and proposed to Ford Motor Company in 1936. Rzeppa’s design uses six balls and an inner and outer race to provide almost constant velocity torque transfer regardless of the joint angle. The joint works in a similar manner to a bevel gear with the balls bisecting the joint angle and functioning as the “teeth” to transmit torque.

The Rzeppa design has been adopted by many aftermarket axle makers, like Drive Shaft Shop (DSS), because of its superior design characteristics and ability to withstand heavy abuse such as sudden torque shock from driving typically found in drag racing and other High Performance Driving Exhibition (HPDE) events. They are less prone to damage and wear and displace the energy applied to them evenly throughout the shaft from the outer stub to the wheel hub.

The stock Nissan 240SX axles do utilize the Rzeppa design, but only in the outer CV joint.

A set of custom made axles utilizing the Rzeppa design for both inner and outer CV joints can be made by DSS for different applications. 240SX MAYHEM target WHP is 400 with torque being fairly close. Additionally, the car is going to be configured for a lowered, wider track over stock. DSS axles start at 500 WHP rating for a price of approximately $560 and go up from there according to what you want. Looking around, we have another option to save some money and to have some axles with the same design features as DSS custom axles that will operate within the suspension parameters desired. Enter the 350Z axles. These axles can be had used for $100 a pair. They are not only cheap to acquire, but also can handle the abuses that modern engineering demands. Additionally, the ends are splined the same for 4-lug or 5-lug hubs for the 240SX. This sounds like winning to me.

OK! Fantastic! Let’s get a set and mount them in! Stop there for a moment…

To utilize the 350Z axles on the R200 differential requires the use of adapter plates that go in between the output stub of the differential and the inner portion of the CV joint. In comes Maverick Motorsports’ Nissan S13/S14/S15 to 350Z Axle Adapters.They will take your existing 2×3 bolt pattern diff output stub and convert it to use a 6×1 bolt pattern axle.  They simply bolt onto the 240sx diff stubs and then you bolt a 6×1 axle directly to the adapter.

IMG_9823_15c56f7a-9570-414e-b8c8-83431f38617b_1024x1024 IMG_9820_1024x1024 Conversion_bolted_up_1024x1024

Need to know…

The 350Z axles combined with the adapters are longer than the S13/S14 axles.  You will either need to have a lowered car, zero camber, or longer Lower Control Arm (LCA) to take up the extra length.  Because of the many different combinations of knuckle, LCA, subframe, alignment, etc it is impossible to anticipate how they will fit across every setup.  Please be prepared to take camber out, widen the track width or similar to accommodate the longer length in this setup.

Please measure from the axle stub to the backside of the hub.  You will need the measurements to match before you can install the axles and not have problems.  If these measurements are too short then the axles will over-compress and damage the cups.

Adapter with 350Z axle total length:

21″ Driver side(left).
22.5″ Passenger side(right)

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