Getting wheel spin like I have an open diff. Saw some spec miata stuff about opening it up and replacing discs. Wanted to see if anyone had a parts list and or a rebuild guild.

 

torsen has disks?? pretty sure its all gears

 

lol @ Spec Miata Wisdom™

 

IIRC, there's a Mazdaspeed clutch-pack LSD available that's legal in Spec Miata -- that's probably what he was talking about.

As for your diff, if it's a Torsen and it's not making loud clunking noises then it's fine. If it is making loud clunking noises, then it's junk. There's not much in between.

--Ian

 

I found this and this is what I'm going on.

 

Isn't that the Fuji diff in that video. AIUI the fuji diff has small clutch plates to add pre-load to the diff, this means that you get drive even when 1 wheel has no torque.

The Torsen's actual limiting slip mechanism is all through gears, it can't wear out, they either work, or the entire differential is pretty much destroyed.

 

The super fuji looks like an open with a large spring inside it. no hexicoil gears.



but that still doesn't mean what's in the video are clutch plates.

 

Torsen units are a mechanical system, but part of that system is frictional force. Here's a great video that describes this:


While those pieces may not technically be clutches, they are part of the process for adjusting bias ratio. It also makes sense that they can wear out over time, reducing the TBR.

From Torsen FAQ: "Since performance (torque bias ratio or TBR) is a direct function of the unit’s internal resistance to differentiate, changing the resistance will change the TBR. Most of this resistance comes from the gear design itself, and cannot be altered. However, there are other frictional factors that can. One of these factors is the friction coefficient of the washers, which the side gears thrust against when torque is applied. We use a variety of different washer types to adjust the TBR. Higher friction washers include plain steel, steel with nickel plating or FNC heat treating, and hardened bronze. To reduce friction, we also use needle bearings as well as washers with a Teflon-based coating."

Not that I'm claiming to be an expert or even knowledgable. It's just an interesting subject to me.

robert

 

 

I love you guys

 

Just pull the e-brake about half way and be done with it for a lap or two, then replace rear brake pads and repeat.