Review: OS Giken R2CD clutch (robk)

Sat, 21 Dec 2013 23:00:37 GMT

I've been driving my car a lot since I got it back a week ago, including in some fairly heavy traffic. Now that I'm used to it, I thought it would be good to do a review of my new clutch, as it will probably help someone in the future (even non MR2 owners who find this via Google search).

Note: the clutch was partially worn-in before I picked up my car, because it spent a lot of time on the dyno.

The clutch is an OS Giken 'R2CD' twin-plate (R = race, 2 = twin-plate, C = floating centre hub, D = dampened).

Here is the description from the OS Giken website regarding their 'R' series of clutches:
"The R Clutch line-up is our highest capacity clutch and was specifically designed for vehicles with a substantial increase in engine power. The unique floating center hub design is built to withstand transmission shock and abuse from high-powered racecars, and matched with our unique billet aluminum clutch cover, variants can easily handle over 1000 hp."

Firstly, yes it is pricey. I can't remember the exact amount but it was over $2000. I purchased it from 'Western Clutch' near Penrith.
With that in mind, there are obviously much more suitable cheaper clutches for cars with up to about 250-270rwkw.
Once you push close to or beyond that power level, I highly recommend this clutch if you are willing to spend the money.

I've been told that sometimes when you pay a lot for a clutch, you only get the really high torque holding capacity but terrible drivability. This clutch isn't like that, it's worth what it costs IMO.

I should also mention that my previous clutch was an Exedy Heavy Duty Button (5 puck) clutch which I was fairly happy with, and it's been a long time since I used a stock clutch. I'm by no means a clutch expert, quite the opposite actually, but at least I've now tried a few different clutches in the same car.

I've always been very picky about clutches, so I was very nervous about learning how to use this new clutch, but I was pleasantly surprised by how quickly I got the hang of it. Being a 'race' clutch you might expect it to be not-so-nice, but really it is totally streetable.

A few other points:
- It definitely can be slipped like a normal clutch for a perfectly smooth take off, but if the revs are too low it will shudder even if you release the clutch very slowly.
- Hill-starts are fine, it's not like some high capacity clutches which require you to do a full launch with wheelspin just to start moving up a hill!
- I've heard mixed opinions about particular types of clutches being light or heavy at the pedal, but with this clutch I would personally describe the pedal weight as light-to-moderate with good feel and progressiveness. I've briefly used excessively heavy clutches before and this definitely isn't one of them.
- I may be mistaken, but I think when the clutch is cold it's slightly harder to take off smoothly the first few times (not significantly), but within 1-2 minutes it's fine. That could just be my clutch foot being unco when my legs are sore or whatever lol.
- Regarding clutch noise, my engine is pretty loud so it's hard to tell, but it seems to be OK apart from a mild rattle sound. I absolutely hate 'bad noises' and rattles in my car, so it must be OK for someone like me to not really notice it too much.

That's all I can think of.
I hope it helps someone make a decision some time :-)