Jump to content
SAU Community

Gmax Vs Coppermix Vs Os Giken Twin

ned
 Share

Recommended Posts

ned Enthusiast

ned

Posted
Posted

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

Link to comment
https://www.sau.com.au/forums/topic/141978-gmax-vs-coppermix-vs-os-giken-twin/
Share on other sites
ookami Experienced

ookami

Posted
Posted

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.

ferni Grand Master

ferni

Posted
Posted
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 :happy: 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 Enthusiast

ned

Posted
  • Author
Posted

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 Community Regular

tuitahi

Posted
Posted

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 Experienced

ookami

Posted
Posted
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 Enthusiast

ned

Posted
  • Author
Posted

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

ned Enthusiast

ned

Posted
  • Author
Posted
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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Kapr
      RB20DE NEO smallbox clutch.

      By Kapr · Posted

      For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
×
×
  • Create New...