Got my Cusco RS 1.5 way LSD today. Looks very nice!! I figured out how to just look at the dif and tell if it's a 1, 1.5, or 2 way unit(See diagram in this link).

The instructions are all in freakin Japanese though, but at least they labled the lockup percentages in English so I can tell how to stack the plates. The problem is, I can't see how they preset the diff from the factory without opening it up!!! Anyone know what lockup percentage the Cusco Diffs come preset too? I only see 100%/80%/60% options. Do you think I should go 60% or 80% for good all around streetability and roadcourse work with a slight emphasis on the roadcourse work on R compound tires. Also, what gear oil to run with this thing?

 

raceboy,

for what its worth I have heard that anything over 60 % is a little to much for normal street driving I have mine at that and it works fine but youll defintely notice a big difference over your former viscous LSD even at 60% as it is much more agressive. IF you want to experiment and set it higher thats of course your option but when I got mine installed it was at the same place the guys from compact sport car mag had theirs done for the record they started @ 100 % went down to 60 and now must be something lower than that because they found those two settings to be TOO agressive..so take that with a grain of salt but even in their writeup review they allude to that also..

hope this helps!

oh as far as oil well since i have a kaaz unit im using their oil I really dont see why that wouldnt work in your case either.. its about 45.00 for each container. looks like this.

diff oil

 

Thanks!

 

Use Mobil 1 Syn 75-90w gear oil for the rear end.

 

Don't forget to break that thing in before you hammer down on it.
Figure 8's for 15 minutes.

 

Use the minimum, 60% lockup rate. If possible, I would even use 30% if you can. I believe Cusco differentials come stacked at 100% lockup from the factory.

You can Mobil gear oil or use what I did, Redline 75W90 Synth gear oil. I liked Redline better than Kaaz's oil. Plus it's easier to get quickly.

 

What locking rate would you say dwnshift? I want a bias toward on track perf, but the car needs to remain streetable, even in the wet. I have been told 100% (basically a solid axle kart like I am used to), but I don't know. I am still thinking that 80% or 60% would be better.

 

Trust me, you don't want to use 100%. The car won't be streetable. 60% is better.

 

Hehe - Steve, you should have just asked me

I am translating the instructions right now for you, so I'll know the lock up percentages, etc later on today. I do know they come at 100%. I just emailed Cusco in Japan to get an idea, given your intended usage for the car, for their recommendation on a good percentage for you.

As for break in - figure 8's are not needed - thats how you break in a gear type diff, not a clutch type. A few minutes of stop and go traffic is all that is needed to break the diff in, then you can hammer down.

Also FWIW (not sure if you knew this or not), but you can actually make this same diff a 2 way as well I'll email you some guidelines for this once I get around to doing the translation.

For oil, 80/90 (dino or synthetic (any good grade is fine - brand really make no difference - Mobil, Castrol, Penzoil, Redline, Royal Purple, etc.), along with the LSD additive.

Adam

 

Thanks Adam, the diff actually goes in next Thurs. I will just use the Redline stuff because it already has the LSD additive in it.

The LSD should make a HUGE difference in my lap times at track days. The car was just mercilessly spinning the inside wheel exiting tighter 2nd and 3rd gear corners wasting a lot of power. Now, all the power should go to the ground. I am looking for a 1+ second improvement in lap times just from the diff alone.

 

I could have sworn our KAAZ was a clutch type. Hmmmm 15 minutes wasted.

 

Sorry for being off topic on this one. I am a newbie. What is LSD ? I know it is a limited slip differential. But .. what does it do ? and where is the placement ? and what is it good for ?

thanks

 

Redline should do just fine -we typically run the same.

Just make sure it has the LSD additive in it....not all of them do IIRC (but its been a long time since I looked, as we just have cases and casesof the stuff for our own cars!).

A for the Kaaz, it is a clutch type - not sure why they recommend the figure 8's - could just be their own methodology, or perhaps its becuase their diffs don't appear to have springs like the RS diff has (KAAZ looks similar to a Cusco MZ). To date, we have only used the RS type from Cusco, as its MUCH quieter according to Cusco than the MZ

Go for those better times Steve - let us know how it works out for you!

 

there are reasons for figure 8 breakin as noted:


faq breakin section

 

Where did you procure this piece of information? The beauty of a gear-type (Torsen / helical) is that no break-in is required and the thing is nearly maintenance free. Clutch types differentials do require a break-in period, just like any type of clutch mechanism does.

 

Came straight from Cusco who answered the email I sent before we started selling their diff's.......

 

Adam, any luck getting English instructions for me yet?

 

I jsut left a message for them to follow up -

moderators - is there a way you cna set the forums up so that we get emailed? Its tough remembering all the threads we are active in, and though we checked the proper box in the user profile, we only get emailed about the vendor ads.....

Adam

 

Ok - managed to have most of it translated, and as it turns out, most of the text is useless stuff talking about what tools you need, jackstands, etc.

However, there is some interesting info on the settings:

It comes at 100% as we already knew - it is perfectly fine to leave it there if you want to. At 100%, it may be a bit "notchy" at low speeds, but will perform fantastic at high speeds. 60% is ultera smooth engagement, but may slip a bit at the high speeds - I ahve never experienced this yet and I ahve run these diffs on cars pushing as much as 600 hp at the wheels before, so 60% is probably your best bet! 80% is a bit in between the two as you would expect.

Good luck and give us some feedback on it when its all in.