powerneedy

So forgive the bad pictures and the mess as this was a quick look at them side by side in a the little free time I had. I wanted to get a Carbonetics in this as well but it was installed in a buddies trans before I could do this. So there are some neat things about both the diffs, But I can say the Cusco, Carbonetics, and spoon pretty much all look identical inside and out to the Kaaz.

In plate diff lsd I only have driving experience from the Kaaz diff from last season, This season I will be running the OS Giken so I will be able to add the diving differences between the two.

***A confirmed busted myth is there IS NOT more discs in the Os Giken in a B series diff but they are bigger and thicker so that will of coarse combat the heat better.

Pros on the OS Giken,
The case and internals on the OS Giken is a little more robust compared to any diff I have handled for a B series
The material on the parts and finish is at a higher standard
The tune-ability of the diff is unreal by changing spring washers, springs and changing plate order.

Pros on the Kaaz
The price
They have the VSS gear machined in the case
The simple fact of the only tune-ability is simple as you can only really flip discs for lock up

Cons on the OS Giken
The price

Cons on the Kaaz
The rumors of why they are bad


Kaaz disc laying on top of the Os Giken for another size comparison

ReedMann

iTrader: (11)

Interesting. Wish I had enough cash to have this so many LSDs that I could take two apart in my kitchen and still have one in my car. Haha thanks for sharing

MBellRacing

Good analysis! I've been working pretty closely with the OS Giken guys and can say they really do engineer the s**t out of their products. They are always working with us, sending us new clutch plates and asking us to experiment with how many we're using and with what oil. The tune-ability (as you mentioned) is quite good between hold-off springs, clutch material, clutch shape, number of clutches, fluid type, ramps, etc.

I drove a car with a Kaaz and it clunked around. The owner said "that's just how it is".

h46it

Wow! I think i need to save my pennies for the a OS!

Dee

Most the clunking in a properly functioning clutch LSD has to do with the initial torque setting. Most people fail to set the initial torque correctly for their intended style of driving.

vtecjj

Great write up on the two lsds. Thanks for doing that. Haven't had any issues with the OS Giken lsds (ran in both B-series and K-series transmissions). I am surprised to see the number of disks are the same between the two. To compensate I suppose, the OS units use thicker plates. I do know that (as you and Matt has stated below) the tune-ability of the OS Giken units provides for a broader range of parts that can be changed to alter the lock-up rate- as a result, getting the diff to lock up sooner on acceleration.

That's true, the "smoothness" of the OS unit doesn't compare to the KAAZ. Especially on decel upon turn-in. In addition, slow speeds (such as in the paddock) don't really concern me. But for what its worth, and for the guys who use these LSDs on the streets: The OS unit is NOT "clunky" at slow speeds (less than 10mph) compared to the KAAZ lsd.

A couple of the problems we've had with the KAAZ in the past are:
1) the plastic speedo sensor gear wore to the point the plastic was shearing.
2) by the end of one season the KAAZ unit needed a rebuild. Characteristically, on track-it acted much like an open diff later in the year
3) Customer service was marginal at best. Tyring to get a hold of specific personal was annoying and fraustrating. Having to deal with unanswered numberous calls and emails resulted in longer than needed downtime for the race car. Only after weeks of follow up and persistence was I able to get the service I needed to obtain replacement parts.

Although the initial costs of the KAAZ is a cheaper buy than the OS Giken LSD, rebuilding the KAAZ does result in added costs down the road. Whereas, in my experience, the OS unit generally outlasts the KAAZ unit, not needing a rebuild.

solo-x

I'll add that OS Giken after sales customer support is exceptional. Powerneedy has my OS Giken from when I parted out my DSP car. It is one of the few parts are considered not selling, even though it was just sitting on the shelf. I liked it that much. The DSP BMW I'm now driving for national level stuff has an OS in it now, and OS is my current top pick for any new builds I'm involved in.

powerneedy

So here is my question I know how much things I can play with on the OS but what settings to go with on a higher hp fwd?

JW racing

If you don't want an aggressive lock up, then try a milder ramp setting. It only appears the M factory and the Cusco allows that. Letting the plates slip a bit more will do the same but create more heat to boot.

Robin6

OS Giken; where to buy for civics?

powerneedy

I really like the lock up but I do know you can over due it.

I think gearspeed is a vendor for them on here?

solo-x

I would recommend calling OS Giken. They really are incredibly helpful. I suspect they'll suggest trying the "box stock" settings to see if a change is necessary first.

MBellRacing

Yup, call them. One of the things we've been tuning on our Camaro GS.R diff is how smoothly it gets into the ramps. We have a lot of torque and it's very easy to snap to oversteer from understeer when the diff locks up too aggressively. OS Giken will be able to walk you through it all between different plates, number of plates, and hold off springs. Ramp angles are honestly one of the last things we tune on our car, it's more of how it locks up under decel versus accel. This will be especially limiting on FWD applications where decel lockup will likely be close to zero.

powerneedy

Makes sense, I will have to give them a call. The OS is a 1 way on the Fwd unless you special order to specs.

Dee

There are LSD's other than Cusco and M Factory that allow you adjust the cam angle (ramp angle). My ancient Mugen could be ordered with 45/50/55 carriers and the ATS 109 2 way diffs come with a carrier that has a 45/50/55/60 setup and the ATS 87 1-way diffs offers 45/55/70 cam angles.

A low initial torque setting will produce better low speed turning without the clunkiness. Initial torque = clutch pack preload.

I have been a fan of the OS Giken LSD since they first started selling LSDs for themselves instead of just building parts for other people. Been contemplating making the switch from Mugen to OS for a while but I guess I'll wait until my current LSD needs an overhaul or fails.

Gearspeed-Performance

iTrader: (1)

The only thing that makes OS a tough decision is the price. They are not cheap by any means for us normal people. But, they work awesome and they have lasted full race seasons during testing without any rebuilding. Just not having to pull a trans and do a rebuild on a diff is enough to justify the higher cost in my opinion Even when you have everything at your disposal to do trans work..it still can be a pain! LOL

Gearspeed-Performance

iTrader: (1)

Thanks! I have 2 in stock right now

dirty19

iTrader: (1)

Break Bread!

ReDemoN

Im saving pennies right now for a Kseries one.
LOL

Bense

any chance of these pics getting reposted?

powerneedy

Done!

Bense

Oh wow, thank you!