Gmax Vs Coppermix Vs Os Giken Twin

[ned]

Hi all,

I need a new clutch in a GTR with ~250rwkw (std turbos with PFC, EBC, and poncams) that is driven daily in Sydney traffic. I have the option of a custom built strengthened single (Jim Berry), vs a OS giken twin (~2 x price), vs a Nismo Gmax twin (~1.3 x price).

MOstly I am interested in holding the current power with no real plans for turbo upgrades or much beyond current power.I have heard good things about the driveability of the Nismo coppermix, but nothing about Gmax, has anyone use dthe older one?

Can anyone comment on the driveability of a Jim Berry single vs the twins for clutch feel, take-up point, driveability, and slip rate?

Cheers

Thanks

Ned

[ned]

I just read the sticky on JB clutches and it sounds good, but still interested in experiences from those that use it for daily driving rather than the track?

Anyone?

Cheers

Ned

[ookami]

whats a Jim Berry clutch twin plate worth or even some details on the single plates would be good? Not sure how an OS giken (can be had for around 1800 if you look hard enough) costs twice as much unless Jim Berry singles does some damn cheap singles. From the people I've spoken to, a lot of single plate puck clutches can be damn right nasty to drivetrains and gearboxes and I have been recommended to steer clear of them unless i wanted to. Nismo G-Max clutches are no longer made and are replaced by the coppermix ones. The Coppermix ones are probably the easiest to drive with out of any twin plates other than the carbon ones. Os Gikens are the cheapest twin plates to buy plates and parts for out of any twin plate - though some clutch places seem to want to charge the earth for them still Os Giken seem to still be bitier than the Nismo Coppermix ones but I'm not sure what their like compared to the Os Giken STR as I'm yet to drive my S13 with one but I'll let oyu know how it compared to the old OS Giken I had.

[Blitz]

Another vote for Nismo Super Coppermix, I have been running one for over a year and its an absolutely fantastic clutch and drives like standard.

[ferni]

whats a Jim Berry clutch twin plate worth or even some details on the single plates would be good? Not sure how an OS giken (can be had for around 1800 if you look hard enough) costs twice as much unless Jim Berry singles does some damn cheap singles. From the people I've spoken to, a lot of single plate puck clutches can be damn right nasty to drivetrains and gearboxes and I have been recommended to steer clear of them unless i wanted to. Nismo G-Max clutches are no longer made and are replaced by the coppermix ones. The Coppermix ones are probably the easiest to drive with out of any twin plates other than the carbon ones. Os Gikens are the cheapest twin plates to buy plates and parts for out of any twin plate - though some clutch places seem to want to charge the earth for them still Os Giken seem to still be bitier than the Nismo Coppermix ones but I'm not sure what their like compared to the Os Giken STR as I'm yet to drive my S13 with one but I'll let oyu know how it compared to the old OS Giken I had.

Jim doesn't sell full clutch kits as far as i know, he just rebuilds them, costs around a grand to have your single or twin rebuilt from him, easy to drive and he says will hold big power....

[ned]

Hi there,

the JB was about $1300, the OS Giken from otomoto delivered was ~2500, and I found a Gmax for ~1700, so theres a fair range. The coppermix aren't available locally that i can find, so at the weight and with potentially GSt and duties wfrom Japan, would be around the OS Giken price I guess.

Cheers

Ned

[tuitahi]

I have a Nismo Gmax twin and its not really fun for daily driving. I was ok with it after a day or so but still stall it every now and then, especially after driving other cars for a while.

Pick up point is ~2/3rds of the way up and its got very little give between off and on.

Not many (if any) of my friends can drive the car anymore but doesn't slip one bit!

[ookami]

I have a Nismo Gmax twin and its not really fun for daily driving. I was ok with it after a day or so but still stall it every now and then, especially after driving other cars for a while.

Pick up point is ~2/3rds of the way up and its got very little give between off and on.

Not many (if any) of my friends can drive the car anymore but doesn't slip one bit!

The pickup point can be adjusted to be closer to the floor you know. The coppermix is 100 times better than the old G-Max, for one the clutch plates are full face not puck type.

[ned]

Thanks for the replies. Jim Berry does sell complete kits, but as you say its from rebuilt hardware and new plates etc.

I have taken a punt on one of his strengthened singles (sprung organic) which will clamp to 3000lbs vs 1900 for the stocker. It comes witha new lightened flywheel, and since I couldnt read a bad thing about them, I decided to save the extra G over the OS or Nismo and put it toward other things. Hopefully I am still smiling in 12 months.

Cheers

Ned

[R31Nismoid]

I would expect you to be similing for a couple of years at least

[tuitahi]

I have taken a punt on one of his strengthened singles (sprung organic)

You didn't go for a carbotic one? I've always thought all the hot Jim Berry clutches were carbotic not organic. Or am I confused?

[ned]

You didn't go for a carbotic one? I've always thought all the hot Jim Berry clutches were carbotic not organic. Or am I confused?

Hi there,

Jim tells me he has a variety of materials at his disposal, with organic giving the closest feel to stock, carbotic taking more punishment again, then I guess its carbon or kevlar. Since I commute 45mins each way daily, his recommendation for a clutch that is easily lived with was, strengthened single in organic.

cheers

Ned