How do you like your twindisc?

[YungTlon]

Hello all I wanted to hear your opinions on whatever twin disc you were running and how you went about breaking it in if you did at all! I see a lot of post about normal clutch break in on here but not twin disc. Dropping a fresh motor in the car and the first start up and drive is going to be on a twin disc not sure what brand yet. How do you like yours?? Thanks!

 

[bastarddsm]

If you have to have one, do not buy any of them unless it has a gear-drive or common hub for both discs. It will trash you input shaft otherwise. Actually it's still going to trash your transmission.

 

[1cleangsx]

Which is why I’m going with a single disc full face ceramic

 

[YungTlon]

If you have to have one, do not buy any of them unless it has a gear-drive or common hub for both discs. It will trash you input shaft otherwise. Actually it's still going to trash your transmission.

well what do you reccomend? I was looking at these options. Basically you’re just saying make sure Both disks “input shaft entry”/ splines where the clutch alignment tool goes in, you’re saying make sure those both math up exact instead of being separate like star shaped?
https://www.tmzperformance.com/shop...isk-clutch-kit-dsm-4g63t-awdfwd-applications/

https://stmtuned.com/collections/1g...products/act-dsm-twin-disc-sint-iron-race-kit

https://stmtuned.com/collections/1g...quarter-master-6-leg-clutch-kit-1g-2g-awd-dsm

thanks for your input

 

[bastarddsm]

I'm saying that if you buy the clutches you listed from stm - the act, or the QM, they will destroy your input shaft. Some users have reported problems in as little as 1000mi. Any light weight clutch is very hard on the transmission as there is no weight to absorb the torsional virbrations from the engine. That just goes into the trans and beats the piss out of everything. Synchros, springs, hubs, sliders, ect.

Lastly they all have just way to much torque capacity. If it's an extreme race application they kinda have their merits, but even then it's not a good idea anymore if you have a mitsu gearset. It just reduces the life of the already short life hard to come by parts. I also don't see any reason that you would need a twin with your mod list. .

 

[Canadian_CD9A]

For a GT3582, I would stay with a good single. How does an 18 year old afford a 6466 700whp build?

 

[jed344]

Honestly if you are asking about twin disks you should have a PPG dog box. That’s only time they make sense to me.

 

[ist dwa]

I absolutely love my twin disc, everything about it. I really like the noise as well, it's kinda like a bov, unique and you know you've got something going on.

There are no draw backs except the drive train rattle on decel, I've just accepted it.

I 100% recommend one.

 

[1GAWD87]

I have the act t1rr twindisk. Act recommends their race clutches to be broken in by a few hard slips letting the clutch cool down in between slips. I personally love the feel of the acts pedal compared to my wifes single disc act

 

[YungTlon]

Haha mod lost hasent been updated yet . Motor is fully built just hasent been put in yet . It’s getting a 6266 .82 ar . And I busted my ass in school and graduated college a few weeks after I turned 18 with an associates in Applied science.. aka welding .

 

[YungTlon]

But anyway thanks guys, when I was breaking in the motor I was gonna do a lot of engine brake pulls and leave it at 10psi gate pressure , I was just asking because I didn’t know if 10psi on a brand new clutch would murder it .. I know I broke in my 2600 but after watching some toms turbo garage started looking into the twindisc

 

[BLKGSX23]

I'm saying that if you buy the clutches you listed from stm - the act, or the QM, they will destroy your input shaft. Some users have reported problems in as little as 1000mi. Any light weight clutch is very hard on the transmission as there is no weight to absorb the torsional virbrations from the engine. That just goes into the trans and beats the piss out of everything. Synchros, springs, hubs, sliders, ect.

Lastly they all have just way to much torque capacity. If it's an extreme race application they kinda have their merits, but even then it's not a good idea anymore if you have a mitsu gearset. It just reduces the life of the already short life hard to come by parts. I also don't see any reason that you would need a twin with your mod list. .

I know your car makes some power, what clutch are you running if you don't mind me asking?

 

[bastarddsm]

But anyway thanks guys, when I was breaking in the motor I was gonna do a lot of engine brake pulls and leave it at 10psi gate pressure , I was just asking because I didn’t know if 10psi on a brand new clutch would murder it .. I know I broke in my 2600 but after watching some toms turbo garage started looking into the twindisc

No the only clutches that really need a break in are the kevlar disc ones. They transfer some material into the mating surfaces that improves grip.
Like a 2600 and 6 puck is good to go out of the box. IDK maybe like an ACT street disc might need some use before it develops full holding power, but I've not seen it

I know your car makes some power, what clutch are you running if you don't mind me asking?

Dude I've had everything. QM twins, Baller Tilton Carbon Twin, The full line of act. Back in the day I used eBay XTD stuff religiously.

Right now the car is on an XTD Stage 4 pressure plate, and an ACT 6 puck disc. The XTD Stg4 is from what I can tell from measuring clamp load, basically a stock parts store replacement pressure plate that is painted. From what I've seen an ACT 2100 is essentially the same thing - though they may have better iron in the shoe. I'm not sure what the car makes for power, but it's gone 10.1@144 on this setup, and it weighs 3150 with driver right now. And it's a fairly torquey setup, I'd bet it makes 550ft*lbs, and probably over 700whp. I'm also using a PPG dogbox, which has a really long first gear (20% more than stock), and on 26" hoosiers, so I just murder the clutch on the launch.
A few weeks prior the car had gone 9.90 at 143 on a 2600/6puck. The disc was shot at that point, and I felt the 2600 was too much, so we tried out the XTD. I'm shocked that it holds. I think a twin disc might last longer in this application, but it's really hard to beat the $100 ACT disc and $70 pressure plate, vs the $500 QM discs.

When I have a synchro trans in the car, my favorite is a ACT2900 and a solid hub street disc. I have been mid 10's at 139 on that combo, and I think it will hold more. A 2600 might even hold it. The only draw back is that using it with slicks is hard on the disc. So if you drag race on slicks a lot, I'd probably opt for a puck disc and a lighter pp.

I've also had good luck with a 2600 and a 4 puck solid in my car. An ACT 4 puck solid is the lightest full size disc for these cars. I need to measure it, but I'm 90% they have less MOI than a set of quartermaster discs. But I think as I've learned, I'd probably say 2100 act disc is the most you want on a stock trans.

I personally really like the ACT discs. They are pretty low cost, available anywhere, and I think they hold the best per clamp load. The drawback on them is the friction material is soft and wears fast, but that's what makes them hold good.

I used to always run sprung hub discs, but any more just solids. The springs ACT puts in a sprung hub are so stiff, they might as well be solid. And then there is less risk of interference with the fingers and the hub preventing full release of the clutch, and shifting problems.

A lot of you younger guys were not around back when the setup for all the fast guys was an ACT3200 and a oem 2g clutch disc. They wore fast, but guys were going 8's at 160 on stock transmissions back then and they were easy to drive. Everyone got all caught up in the hype with this new technology, and we took several steps backwards. Who cares if the QM lasts longer, if you can't get the car off the line.....

.

 

[GST with PSI]

Dude I've had everything.

How about the Exedy tripple? It's supposed to have the weight the twins lack for better drivability and smoother operation.

 

[bastarddsm]

How about the Exedy tripple? It's supposed to have the weight the twins lack for better drivability and smoother operation.

Have not had one of those. I did have my tilton on a 25lb flywheel, so it had essentially the same flywheel inertia as a streetlite/act pp. Defiantly improved drive ability, and reduced harmonic damage to the trans. but it still has a big problem, 900 ft*lbs capacity, which is what the excedy triple probably has. And now you have a real BFH behind that to really hammer the trans. FWIW if you wanted to try it, you can get a heavier flywheel for the quartermaster. Same results, much less $$


Something that few people understand/know about is that what makes the QM shift good isn't the weight, it's the clean release. The QM cover and diaphragm is very very rigid compared to a stock type pressure plate. There is much less flex in the system, and thus much less lost motion. It only takes about 0.100" of tob movement to release a QM, where as a stock dsm clutch takes like 0.250" and a 2600 is over 0.300" Stock our tob moves about 0.350" IRCC (these numbers are pulled off the top of my head, i have it written down somewhere) You can see why a QM shifts good, it gets plenty of release, and a 2600 barely gets released. This is also why the QM has such brutal engagement - it builds up it's clamp load so quickly, and not only that, it build up a TON of torque capacity quickly. Just ballpark it and say a QM gains 7ft*lbs per 0.001", a 2600 is only 1.6 ft*lbs per 0.001" If the cover and fingers on a QM flexed more it would be more manageable. I say QM because it's easier than saying twin, or PTT/QM/TIlton/Excedy, but they all work the same. PTT, QM, Tilton all have softer springs = less torque capacity. For some reason they all ship them with the stiffest springs. If you try and talk to them about it, they won't work with you, because in their eyes the clutch should never slip, the tires should. Well, fastest cars in the world use clutch slip to manage power, not tire slip. In our cars we just break shit if we try and use tire slip. If we could spring them down to like 450-500 ft*lbs that would be a much better deal. Both tilton and QM used to make 8.5" singles using a forged cover like a qm. Those would have been a sweet setup for us I think. I'm pretty sure tilton offered one for a dsm at one time.

From my experiments/testing, I'm pretty sure a stock dsm driveline has a torque capacity of about 350-400ft*lbs in first gear. Anything more than that, and it either spins tires, or breaks parts. Obviously this isn't a hard/fast rule, but generally. Run a welded diff, and the capacity comes up, but also moves more toward breaks parts. What this mean is that you gotta be able to find that 400 ft*lbs point in your clutch, and hold it there till the disc speed matches pressure plate speed. Then let er lock up.

What a lot of people try and do is hit the tires, and let them do the slipping until track speed catches up to tire speed. That's hard because once a tire spins, it takes less torque to keep it spinning then it did to break it loose. So you use 2 step rpm and excess clutch capacity to knock them loose, then hope the track speed does not catch tire speed until you are going fast enough to stay on top of the turbo.

After having a Tilton carbon for a while, I think a single 8" carbon setup to hold like 400 ft*lbs cold would be tits. It'll shift killer, launch easy, and the little bit of slip it has will put enough heat into it to make it grab down track. Excedy was close with the single carbons, but missed the ball by using it on steel floaters.

 

[YungTlon]

No the only clutches that really need a break in are the kevlar disc ones. They transfer some material into the mating surfaces that improves grip.
Like a 2600 and 6 puck is good to go out of the box. IDK maybe like an ACT street disc might need some use before it develops full holding power, but I've not seen it


Dude I've had everything. QM twins, Baller Tilton Carbon Twin, The full line of act. Back in the day I used eBay XTD stuff religiously.

Right now the car is on an XTD Stage 4 pressure plate, and an ACT 6 puck disc. The XTD Stg4 is from what I can tell from measuring clamp load, basically a stock parts store replacement pressure plate that is painted. From what I've seen an ACT 2100 is essentially the same thing - though they may have better iron in the shoe. I'm not sure what the car makes for power, but it's gone 10.1@144 on this setup, and it weighs 3150 with driver right now. And it's a fairly torquey setup, I'd bet it makes 550ft*lbs, and probably over 700whp. I'm also using a PPG dogbox, which has a really long first gear (20% more than stock), and on 26" hoosiers, so I just murder the clutch on the launch.
A few weeks prior the car had gone 9.90 at 143 on a 2600/6puck. The disc was shot at that point, and I felt the 2600 was too much, so we tried out the XTD. I'm shocked that it holds. I think a twin disc might last longer in this application, but it's really hard to beat the $100 ACT disc and $70 pressure plate, vs the $500 QM discs.

When I have a synchro trans in the car, my favorite is a ACT2900 and a solid hub street disc. I have been mid 10's at 139 on that combo, and I think it will hold more. A 2600 might even hold it. The only draw back is that using it with slicks is hard on the disc. So if you drag race on slicks a lot, I'd probably opt for a puck disc and a lighter pp.

I've also had good luck with a 2600 and a 4 puck solid in my car. An ACT 4 puck solid is the lightest full size disc for these cars. I need to measure it, but I'm 90% they have less MOI than a set of quartermaster discs. But I think as I've learned, I'd probably say 2100 act disc is the most you want on a stock trans.

I personally really like the ACT discs. They are pretty low cost, available anywhere, and I think they hold the best per clamp load. The drawback on them is the friction material is soft and wears fast, but that's what makes them hold good.

I used to always run sprung hub discs, but any more just solids. The springs ACT puts in a sprung hub are so stiff, they might as well be solid. And then there is less risk of interference with the fingers and the hub preventing full release of the clutch, and shifting problems.

A lot of you younger guys were not around back when the setup for all the fast guys was an ACT3200 and a oem 2g clutch disc. They wore fast, but guys were going 8's at 160 on stock transmissions back then and they were easy to drive. Everyone got all caught up in the hype with this new technology, and we took several steps backwards. Who cares if the QM lasts longer, if you can't get the car off the line.....

.

Good information , thank you

 

[We're on Boost]

It only takes about 0.100" of tob movement to release a QM, where as a stock dsm clutch takes like 0.250" and a 2600 is over 0.300" Stock our tob moves about 0.350" IRCC (these numbers are pulled off the top of my head, i have it written down somewhere)

Cool, I've been wanting to know these numbers for a while!
If you can find where you've got these numbers written down, could you give a holler back to verify?
Also, if the TOB stock moves 0.350" then I suppose the end of the fork would move about 0.650" right?
I mean, that is just by scaling the "rocker ratio" off the drawing in the FSM, and the 0.650" I'm talking about would be measured where I put the red arrow on the drawing below:

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[clutchtamer]

From my experiments/testing, I'm pretty sure a stock dsm driveline has a torque capacity of about 350-400ft*lbs in first gear. Anything more than that, and it either spins tires, or breaks parts. Obviously this isn't a hard/fast rule, but generally. Run a welded diff, and the capacity comes up, but also moves more toward breaks parts. What this mean is that you gotta be able to find that 400 ft*lbs point in your clutch, and hold it there till the disc speed matches pressure plate speed. Then let er lock up.

...which is exactly what my Hitmaster system was designed to help a racer do....

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Grant

 

[clutchtamer]

Here's a comparison of my ClutchTamer and Hitmaster products, notice how the stepped curve of the Hitmaster is able to hit deeper in the clutch's sweet spot zone without blowing thru it too quickly. Also notice how the stepped curve of the Hitmaster can get to full clutch clamp pressure much quicker than the ClutchTamer...

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The next graph shows why simple hydraulic restriction (Magnus/Clutchmasters/Tilton) is a poor way for a drag racer to control clutch engagement. Notice how long it takes for them to reach the sweet spot, then how they blow thru the sweet spot too quickly...

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You can change the rate of clutch engagement by changing the size of simple restriction, but there's always a compromise to be made between reaction time and having an effective amount of clutch slip.

Grant

 

[ceedawg]

No the only clutches that really need a break in are the kevlar disc ones. They transfer some material into the mating surfaces that improves grip.
Like a 2600 and 6 puck is good to go out of the box. IDK maybe like an ACT street disc might need some use before it develops full holding power, but I've not seen it


Dude I've had everything. QM twins, Baller Tilton Carbon Twin, The full line of act. Back in the day I used eBay XTD stuff religiously.

Right now the car is on an XTD Stage 4 pressure plate, and an ACT 6 puck disc. The XTD Stg4 is from what I can tell from measuring clamp load, basically a stock parts store replacement pressure plate that is painted. From what I've seen an ACT 2100 is essentially the same thing - though they may have better iron in the shoe. I'm not sure what the car makes for power, but it's gone 10.1@144 on this setup, and it weighs 3150 with driver right now. And it's a fairly torquey setup, I'd bet it makes 550ft*lbs, and probably over 700whp. I'm also using a PPG dogbox, which has a really long first gear (20% more than stock), and on 26" hoosiers, so I just murder the clutch on the launch.
A few weeks prior the car had gone 9.90 at 143 on a 2600/6puck. The disc was shot at that point, and I felt the 2600 was too much, so we tried out the XTD. I'm shocked that it holds. I think a twin disc might last longer in this application, but it's really hard to beat the $100 ACT disc and $70 pressure plate, vs the $500 QM discs.

When I have a synchro trans in the car, my favorite is a ACT2900 and a solid hub street disc. I have been mid 10's at 139 on that combo, and I think it will hold more. A 2600 might even hold it. The only draw back is that using it with slicks is hard on the disc. So if you drag race on slicks a lot, I'd probably opt for a puck disc and a lighter pp.

I've also had good luck with a 2600 and a 4 puck solid in my car. An ACT 4 puck solid is the lightest full size disc for these cars. I need to measure it, but I'm 90% they have less MOI than a set of quartermaster discs. But I think as I've learned, I'd probably say 2100 act disc is the most you want on a stock trans.

I personally really like the ACT discs. They are pretty low cost, available anywhere, and I think they hold the best per clamp load. The drawback on them is the friction material is soft and wears fast, but that's what makes them hold good.

I used to always run sprung hub discs, but any more just solids. The springs ACT puts in a sprung hub are so stiff, they might as well be solid. And then there is less risk of interference with the fingers and the hub preventing full release of the clutch, and shifting problems.

A lot of you younger guys were not around back when the setup for all the fast guys was an ACT3200 and a oem 2g clutch disc. They wore fast, but guys were going 8's at 160 on stock transmissions back then and they were easy to drive. Everyone got all caught up in the hype with this new technology, and we took several steps backwards. Who cares if the QM lasts longer, if you can't get the car off the line.....

.

Pmd

 

[taylorvw]

Without starting a new thread, I and the tons of info here I feel its proper to bump while in question..

bastarddsm/anyone have any first hand experience with the Competition Clutch twin?

 

[bastarddsm]

nope, but it's likely it;ll act just like a qm, only it'll eat up input shaft splines faster. .

 

[1992GsT]

Without starting a new thread, I and the tons of info here I feel its proper to bump while in question..

bastarddsm/anyone have any first hand experience with the Competition Clutch twin?

I have one. It is a very good clutch just noisy as hell I have exedy twin disc on my evo and the chatter went away. The competition I have on my 1g still chatters til this day!