4 puck versus 6 puck
09-15-07, 10:03 AM
#1
4 puck versus 6 puck
I was doing some clutch shopping the other day and came across an site that said:
If you have an NA motor, we recommend our sprung 4 puck clutch.
If you have a Turbo motor, we recommend our sprung 6 puck clutch.
On ACT's site they recommend a 4 puck for cars with a smaller flywheel and a 6 puck for cars with a larger flywheel.
I have an NA that's primarily for the track/autox that currently sees very little daily/street driving. If that's the case, I'm leaning towards an ACT sprung 4-puck right now. Anyone have any opinions/clarifications that they can provide so I can better understand how to pick a clutch?
If you have an NA motor, we recommend our sprung 4 puck clutch.
If you have a Turbo motor, we recommend our sprung 6 puck clutch.
On ACT's site they recommend a 4 puck for cars with a smaller flywheel and a 6 puck for cars with a larger flywheel.
I have an NA that's primarily for the track/autox that currently sees very little daily/street driving. If that's the case, I'm leaning towards an ACT sprung 4-puck right now. Anyone have any opinions/clarifications that they can provide so I can better understand how to pick a clutch?
09-15-07, 12:08 PM
#2
I can tell you that with the light RB flywheel and a 6-puck my TII is a giant pain in the *** in stop and go traffic. Works great on track though. The 6-puck has more friction area than the 4, so I think the tradeoff is more holding strength and durability on the 6-puck and slightly easier engagement on the 4. I could be wrong though.
09-19-07, 07:38 PM
#7
Senior Member
Simple.
Pretend you have a 1000psi pressure plate. (Using these numbers for simplicity)
Now divide 1000 pounds per square inch by 6.
166.6 Pounds of force on each puck.
1000 Pounds of force on 4 Pucks. 250 Pounds per puck.
/shrug
Granted there is more to it. However to keep it simple, the 4 puck will have harsher engagement, and tend to bite more aggressively.
The 6 Puck will be a bit smoother as there is more surface area, and it will have a bit more progressibe bite.
Now this also is figuring that the pucks ar all of equal size, and material too.
The other advantage on a non-drag race application. The 4 puck and 6 puck clutches will handle high rpm downshifts better. As well as heavy abuse. They DO generate a lot of heat, and once you use a 4 or 6 puck on that flywheel, you will likely not be able to change out to a conventional one, as they wear the friction surface more aggressively. (resurface, and or replace friction material on flywheels that allow you to)
The sprung portion I am pretty sure you are referring to, would be the center springs. These absorb engagement shock, thereby lessening the wear on the driveline components such as the u-joints. It will make for smoother starts, but not really that much smoother engagement.
The second area of "sprung" functionality on a clutch is between the friction survace, front and back. IE, the side touching the flywheel and the side touching the pressure plate. On a stock clutch there is a bit of compressability in the clutch that allows the clutch to smoothly engage, and not chatter as it starts to bite, while you let off on the clutch pedal.
I forget the model..Mazdatrix, or maybe ACT has one that is I believe a 6 puck that is double sprung. It has a sprung hub, as well as the sprung faces. It also has metallic pucks.
The advantage of that particular clutch is a nice drivability, and ease of engagement, with the high holding ability of a metallic puck.
In a higher horsepower non-drag race application that sees street use, I would go with something like that for my clutch disk.
In a race application with minimal street use, I would stay with a unsprung across the board. Simply to minimise the failure points. Also in the race world if the clutch disk is 1 pound VS 5. /shrug thats a bucket of floor insulation.
Pretend you have a 1000psi pressure plate. (Using these numbers for simplicity)
Now divide 1000 pounds per square inch by 6.
166.6 Pounds of force on each puck.
1000 Pounds of force on 4 Pucks. 250 Pounds per puck.
/shrug
Granted there is more to it. However to keep it simple, the 4 puck will have harsher engagement, and tend to bite more aggressively.
The 6 Puck will be a bit smoother as there is more surface area, and it will have a bit more progressibe bite.
Now this also is figuring that the pucks ar all of equal size, and material too.
The other advantage on a non-drag race application. The 4 puck and 6 puck clutches will handle high rpm downshifts better. As well as heavy abuse. They DO generate a lot of heat, and once you use a 4 or 6 puck on that flywheel, you will likely not be able to change out to a conventional one, as they wear the friction surface more aggressively. (resurface, and or replace friction material on flywheels that allow you to)
The sprung portion I am pretty sure you are referring to, would be the center springs. These absorb engagement shock, thereby lessening the wear on the driveline components such as the u-joints. It will make for smoother starts, but not really that much smoother engagement.
The second area of "sprung" functionality on a clutch is between the friction survace, front and back. IE, the side touching the flywheel and the side touching the pressure plate. On a stock clutch there is a bit of compressability in the clutch that allows the clutch to smoothly engage, and not chatter as it starts to bite, while you let off on the clutch pedal.
I forget the model..Mazdatrix, or maybe ACT has one that is I believe a 6 puck that is double sprung. It has a sprung hub, as well as the sprung faces. It also has metallic pucks.
The advantage of that particular clutch is a nice drivability, and ease of engagement, with the high holding ability of a metallic puck.
In a higher horsepower non-drag race application that sees street use, I would go with something like that for my clutch disk.
In a race application with minimal street use, I would stay with a unsprung across the board. Simply to minimise the failure points. Also in the race world if the clutch disk is 1 pound VS 5. /shrug thats a bucket of floor insulation.
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09-19-07, 07:58 PM
#8
Old [Sch|F]ool
6 pucks drive okay.
My car has a 4 puck. I *HATE* it. It's almost impossible to drive, there is about 1/4" of pedal travel between "disengaged" and "stalled/spinning the tires".
http://www.youtube.com/watch?v=VdbMcLhjWIo
Grips good though...
Also... unsprung hubs are ONLY for road racing applications. Standing starts or rough shifting equal rapid damage. My boss's dad told me that back inna day (early 60's) they used to twist the input splines of their transmissions with unsprung puck clutches. A T10's input shaft makes anything rotary look like something out of a watch.
My car has a 4 puck. I *HATE* it. It's almost impossible to drive, there is about 1/4" of pedal travel between "disengaged" and "stalled/spinning the tires".
http://www.youtube.com/watch?v=VdbMcLhjWIo
Grips good though...
Also... unsprung hubs are ONLY for road racing applications. Standing starts or rough shifting equal rapid damage. My boss's dad told me that back inna day (early 60's) they used to twist the input splines of their transmissions with unsprung puck clutches. A T10's input shaft makes anything rotary look like something out of a watch.
09-19-07, 08:28 PM
#9
Senior Member
As I said above. Race application the unsprung are best.
Also remember its what the individual is used to. If you are 16, and have limited manual driving time, and are not used to a really harsh, quick engagement. May want to go with a CF dual friction or something.
Also if youre late 30s/40s, and drive it daily, it will get old fast.
(me)All my RX-7s have a 4 puck unsprung ACT disk. Im used to it, blip of the throttle, it starts to engage, and I blip and go. There is a slight shudder, and you're moving. In the rain there is a light spinning, and I modulate gently and were off.
Stock clutches and I dont get along. I am too abusive of the driveline at times to have them stand up for more than 4 or 6 months of mostly street use.
Thats why I bought a daily driver other than the 7s to go to work and back when lazy.
09-19-07, 10:59 PM
#10
Lives on the Forum
4 puck has harsher and more abrupt engagement.
All that rotating force divided over less pucks will mean more heat generated per puck.
More heat means the clutch disc will engage faster.
Unsprung puck clutch discs should not be used in a street vehicle.
Engagement breaks engine / trans / diff mounts.
-Ted
All that rotating force divided over less pucks will mean more heat generated per puck.
More heat means the clutch disc will engage faster.
Unsprung puck clutch discs should not be used in a street vehicle.
Engagement breaks engine / trans / diff mounts.
-Ted
09-20-07, 09:11 AM
#11
Fast-Trash
I run the ACT 6-puck with the Extreme pressure plate. I drive on the street and track the car occassionally. The 6-puck has so far stood up to dozens of 7500rpm two-step drag launches on slicks without letting me down. It's held 436whp without slipping once. I'm very impressed.
Driving in gridlock is a pain, but once you get used to driving an unsprung puck everything else will seem like weaksauce. I drove a stock GSL-SE the other day, and I swore up and down that the master cylinder had failed. I just wasn't used to something so soft and completely unresponsive.
The only ACT 4-puck car I've ever driven was a full ITS race car. I don't think it's any worse than the ACT 6, but I wouldn't go any further than a 6-puck in anything that sees time on the street.
Driving in gridlock is a pain, but once you get used to driving an unsprung puck everything else will seem like weaksauce. I drove a stock GSL-SE the other day, and I swore up and down that the master cylinder had failed. I just wasn't used to something so soft and completely unresponsive.
The only ACT 4-puck car I've ever driven was a full ITS race car. I don't think it's any worse than the ACT 6, but I wouldn't go any further than a 6-puck in anything that sees time on the street.
09-20-07, 09:37 AM
#12
I have a 4-puck in my 75 RX-3 and 6-puck in the 73 RX-3 (was in my FB). A 4-puck with 3500 lbs pressure plate works like an "On and Off" switch with no in-between. I like it more than the 6puck even for street use. But again, Im always looking for the unexpected...
09-20-07, 10:16 AM
#13
I'm looking for a clutch right now and this thread has made 6 puck sprung out to be a pretty good choice for my application (street, lots of power, some spirited driving). The other possible choice is full faced organic with no springs (marcels?) between sides like the RB HD disc for example.
I want something that I can abuse that will last a while.
I want something that I can abuse that will last a while.
09-20-07, 10:43 AM
#15
ACT 6 puck sprung and HD pressure plate would be my recommendation to you.
I'm waiting on Fidanza to release their 4 puck full kevlar disk and pressure plate. Apparently, it's more streetable than the carbon/kevlar disks that ACT produces.
I'm waiting on Fidanza to release their 4 puck full kevlar disk and pressure plate. Apparently, it's more streetable than the carbon/kevlar disks that ACT produces.
09-20-07, 11:48 AM
#16
I'm considering many angles.
I installed an RB street strip pressure plate and HD disc in my bro's RX-4 wagon. It seemed inadequate to tell you the truth. Some what heavy car, supercharged, tall geared diff (3.636). It felt like you're starting in 2nd gear unless you're on level ground. I tried to do some donuts in a dirt/gravel field and it slipped/burned the clutch pretty bad.
It had a GSL-SE flywheel and 225mm clutch components, and it slipped fairly easily! The flywheel was freshly resurfaced but had broken in for about 800 miles. I don't understand why it couldn't handle gravel. It reminds me of my bro's GSL-SE in some snow. The attempts to burn out in snow burned the clutch pretty bad too, but it was just stock clutch components. Same flywheel though.
Maybe it's a combination of high RPM and the organic disc slipping? This is something I wish to avoid. Uh, the slipping, not the high RPM.
Now that I think about it, the street strip pressure plate in the RX-4 felt maybe slightly weaker than my REPU (which comes stock with some pretty strong clutch components such as a 9 bolt pressure plate and full faced organic disc with heavy marcels). I can remember the RX-4's old stock pressure plate was so weak you could push the pedal with one finger practically. The street strip upgrade was a major improvement but still not quite 'there' yet.
I recently had a chance to compare my REPU's pedal effort to a friend's 1st gens. One has a 215mm on aluminum and the other is a freshly installed 225mm on a stock flywheel. The 215mm is possibly a race presure plate. I just remember it was pretty heavy, and it has enough grip to break 'em loose in gear with a supercharger on a 13B. The other is a fresh rebuild, and the pedal effort is about the same as the other one. As for how they compare to the REPU, They are marginally stiffer. I would have no problem driving either one of them daily. That is what I want for my project; a little stiffer than the REPU, and will not slip at high RPM in frikken gravel.
Both RX-7s have race or street strip pressure plates. There is no way to know for sure because both were purchased back in '00. One set's been used as a daily driver and the other sat for many years. I believe I have a way to tell what type of pressure plates they are. I have a street strip pressure plate in 215mm and a worn out HD disc that we used in the RX-4 before the upgrade from the old stock heavy 30 pound 215mm flywheel to the 225mm GSL-SE flywheel. I'll will try this pressure plate and probably a good used stock disc because the HD disc is done for (the 30 pound flywheel should have been resurfaced because its iregular surface killed the disc). The pressure plate is fine. I have a brand new light steel flywheel to use as well.
I'll test the 215mm street strip pressure plate with the stock disc and observe the pedal effort. If it's noticeably weaker than my friend's and the REPU, I'll get a race pressure plate or an ACT Heavy Duty. If it feels within the same general area, accounting for the mushier pedal feel of the stock disc of course, I'll just get a street strip pressure plate and call it good.
As for the disc itself, I'll have to drive my friend's cars around for a little bit and compare to mine before I make my final decision. I've got my eye on this little number though.
I installed an RB street strip pressure plate and HD disc in my bro's RX-4 wagon. It seemed inadequate to tell you the truth. Some what heavy car, supercharged, tall geared diff (3.636). It felt like you're starting in 2nd gear unless you're on level ground. I tried to do some donuts in a dirt/gravel field and it slipped/burned the clutch pretty bad.
It had a GSL-SE flywheel and 225mm clutch components, and it slipped fairly easily! The flywheel was freshly resurfaced but had broken in for about 800 miles. I don't understand why it couldn't handle gravel. It reminds me of my bro's GSL-SE in some snow. The attempts to burn out in snow burned the clutch pretty bad too, but it was just stock clutch components. Same flywheel though.
Maybe it's a combination of high RPM and the organic disc slipping? This is something I wish to avoid. Uh, the slipping, not the high RPM.
Now that I think about it, the street strip pressure plate in the RX-4 felt maybe slightly weaker than my REPU (which comes stock with some pretty strong clutch components such as a 9 bolt pressure plate and full faced organic disc with heavy marcels). I can remember the RX-4's old stock pressure plate was so weak you could push the pedal with one finger practically. The street strip upgrade was a major improvement but still not quite 'there' yet.
I recently had a chance to compare my REPU's pedal effort to a friend's 1st gens. One has a 215mm on aluminum and the other is a freshly installed 225mm on a stock flywheel. The 215mm is possibly a race presure plate. I just remember it was pretty heavy, and it has enough grip to break 'em loose in gear with a supercharger on a 13B. The other is a fresh rebuild, and the pedal effort is about the same as the other one. As for how they compare to the REPU, They are marginally stiffer. I would have no problem driving either one of them daily. That is what I want for my project; a little stiffer than the REPU, and will not slip at high RPM in frikken gravel.
Both RX-7s have race or street strip pressure plates. There is no way to know for sure because both were purchased back in '00. One set's been used as a daily driver and the other sat for many years. I believe I have a way to tell what type of pressure plates they are.
I have a street strip pressure plate in 215mm and a worn out HD disc that we used in the RX-4 before the upgrade from the old stock heavy 30 pound 215mm flywheel to the 225mm GSL-SE flywheel. I'll will try this pressure plate and probably a good used stock disc because the HD disc is done for (the 30 pound flywheel should have been resurfaced because its iregular surface killed the disc). The pressure plate is fine. I have a brand new light steel flywheel to use as well.I'll test the 215mm street strip pressure plate with the stock disc and observe the pedal effort. If it's noticeably weaker than my friend's and the REPU, I'll get a race pressure plate or an ACT Heavy Duty. If it feels within the same general area, accounting for the mushier pedal feel of the stock disc of course, I'll just get a street strip pressure plate and call it good.
As for the disc itself, I'll have to drive my friend's cars around for a little bit and compare to mine before I make my final decision. I've got my eye on this little number though.
09-20-07, 01:13 PM
#20
This clutch is for my autox/track car, which won't see much street driving, so I'm sacrificing some streetability. Having said that, it's not a stripped out car and is still street legal, so I drive my car to those events instead of trailering it. That's why I went with the sprung disc. If I had a stripped out car, you can be sure I'd be using this clutch instead.
Now, if I had a dog-box, I would definitely try for this one
Now, if I had a dog-box, I would definitely try for this one
09-21-07, 01:08 PM
#21
I've put in a lot of miles driving puck clutches on the street and regardless of the number of pucks (because they are all basically on/off until you reach their limit), the key to making them easy to deal with is the right final drive ratio...the shorter the better. With a 4.88:1 gear, driving a 4-puck is a breeze, even in traffic. Of course, then you are grabbing 2nd gear before you cross the crosswalk, but it's a good tradeoff.
09-21-07, 05:09 PM
#23
King of the Loop
I just wanted to drop my 2 cents in here. I have had 6 pucks in my car in the past and I currently drive an unsprung 4 puck daily. It is very harsh on the driver and the driveline. I have broken my trans mounts and my diff mount in just a few months but the engagement when changing gears at high rpms is worth it.
Its pretty easy to lose traction from a dig if you have crappy tires but despite the few downsides I wouldnt go back to a 6 or a full faced clutch if you paid me.
PS: The 4 puck is even more fun when you watch other people (friends, instructors ect) stall over and over again while trying to drive it after you warned them and theytold you that a 4 puck is no big deal.
Its pretty easy to lose traction from a dig if you have crappy tires but despite the few downsides I wouldnt go back to a 6 or a full faced clutch if you paid me.
PS: The 4 puck is even more fun when you watch other people (friends, instructors ect) stall over and over again while trying to drive it after you warned them and theytold you that a 4 puck is no big deal.
09-21-07, 06:58 PM
#24
Old [Sch|F]ool
Oddly enough, I like stock clutches because they engage smoothly, this means you don't break things and you don't break the tires loose so easily on a shift. Stock clutch discs are only $100ish and seem to last me longer than the rest of the car.
ONE disc, one USED disc pulled from a junkyard S5 engine, lasted me about 50k, three seasons of rallycross, and about five or six transmissions, and it's just starting to slip, but the rest of the car is junk. The new car has the ACT thing.
ONE disc, one USED disc pulled from a junkyard S5 engine, lasted me about 50k, three seasons of rallycross, and about five or six transmissions, and it's just starting to slip, but the rest of the car is junk. The new car has the ACT thing.
