Well, another real noodle scratcher of a question (dripping with sarcasm)

well i need to get a new clutch/flywheel for the 260 box and was just wondering what people would recommend? brand and price i should be paying

Cheers

Joe

anyone?

K R Clutch Engineering in queensland. Either that or K B Clutch engineering, I can never remember. I've got a receipt sitting on my car so I'll get the details then but I seem to remember they've changed names. Keith is a top bloke, I got my 5-puck ceramic, 1100kg pressure plate for $380.

Dave

_________________
USA Daily: 2014 Nissan GT-R, very minor modifications for the track
USA Project: 1978 280Z, minor suspension upgrades, VK56DE conversion in progress. SOLD
AUS Race Car: 1973 240Z, L28ET, Autronic, GT35R. SOLD
AUS Project: 1972 1600, 3200km old S15 SR20DET, ground up rebuild. SOLD

thanks dave,

Ok well i understand the the more pucks you have the better, but what exactly is a puck?

Not really the more pucks the better.

A 'puck' on a clutch refers to the type of clutch plate. A normal clutch plate is a full 'disc' shape, where a puck clutch has 'paddles' instead of the full disc. The less amount of pucks means more clamping pressure because of less surface area. So a 5 puck clutch will have less clamping pressure than a 4 puck clutch but might be a bit more 'driveable'
hope this makes sense.

Heres a pic of a '5 puck' clutch:

-Dave

Davo,

This theory seems to get around quite a bit. I don't fully understand that. From what I can tell (given that a ceramic/brass puck and a metal flywheel won't be deforming) the only way you increase the torque capability of the clutch is by either changing the coefficient of friction between the surfaces, or by increasing the clamping pressure (which is the pressure resulting from the prongs on the pressure plate - not breakaway torque which is the torque required to make it slip).

I have never driven clutches back to back with different number of pucks so I wont' argue anything about drivability, though that seems to be the appraisal given by people who have: more pucks makes it more drivable.

So in this respect, the more pucks the easier it will be to drive. Without any decrease in breakaway torque. Please don't take this as advice/gospel, I'm just thinking out loud.

Dave

_________________
USA Daily: 2014 Nissan GT-R, very minor modifications for the track
USA Project: 1978 280Z, minor suspension upgrades, VK56DE conversion in progress. SOLD
AUS Race Car: 1973 240Z, L28ET, Autronic, GT35R. SOLD
AUS Project: 1972 1600, 3200km old S15 SR20DET, ground up rebuild. SOLD

The way i understand it is, having less pucks on the clutch plate gives more pressure at each puck, since having less surface gives more pressure at each point.
With more pucks, you have more surface area so the clamping torque is spread across a greater area. You still have the same clamping force but spread over a greater surface area. So the more pucks, the greater the likelyhood of the clutch slipping. Which in turn helps drivability by riding the clutch a little.

Ive also never driven each clutch back to back so cant speak from experience and im also just thinking out loud

Davo,

You are correct in that having less pad/puck area will mean there is less pressure at each point given a constant force as:

pressure = force / area

I believe the confusion stems from the fact that the FORCE applied to the friction plate is termed `clamping pressure'. This puts pressure in people's minds, whereas I cannot see how it is at all relevant. The force (lateral) required to make two non-deforming materials slide is goverened by:

F = uN

u is the aforementioned coefficienct of friction
N is the perpendicular FORCE

The pressure on each square inch of the pads is irrelevant.

Dave

_________________
USA Daily: 2014 Nissan GT-R, very minor modifications for the track
USA Project: 1978 280Z, minor suspension upgrades, VK56DE conversion in progress. SOLD
AUS Race Car: 1973 240Z, L28ET, Autronic, GT35R. SOLD
AUS Project: 1972 1600, 3200km old S15 SR20DET, ground up rebuild. SOLD

I think i understand where your coming from but i was under the impression less surface area with the same given force means more pressure. Opposite of what youve said here:
I think i might be missing something. Sorry if i seem a bit dosile, just dont exactly understand following your formula. Its a bit different from the way ive always understood.

-Davo

Stupid damn typos!

What I meant is what you said:

You are correct in that having MORE pad/puck area will mean there is less pressure at each point given a constant force as:

pressure = force / area


Stupid fingers.

Dave

_________________
USA Daily: 2014 Nissan GT-R, very minor modifications for the track
USA Project: 1978 280Z, minor suspension upgrades, VK56DE conversion in progress. SOLD
AUS Race Car: 1973 240Z, L28ET, Autronic, GT35R. SOLD
AUS Project: 1972 1600, 3200km old S15 SR20DET, ground up rebuild. SOLD

Understand,
Thanks mate. Though i was going mad there

hmmm WOW Complex, but i understand now, now i have had no experience driving with a puck cluctch (to my knowledge anyway) so what has everyone used on a street/track car and had a good life aswel as good driveability??

thanks

Joe

F = uN

= FUN

So less pads = more FUN

My car has a 4 puck ceramic in it, with a standard flywheel it has good clamping pressure and is easy to use, trick is not to slip it to much ie give it a few revs then let it out quickly. I wouldnt like to use one on a daily basis in traffic, not that i have tried it but think it would be a pain.

On the track its great grabs quickly and doesnt slip at all. I have just rebuilt the motor and it basically has a frisbe for a flywheel with another but greater diameter 4 puck clutch in it.

Luke

thanks all