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found this on atruck site..

Quite interesting really..

Dual mass vs single mass:

Some notes on application pros and cons:

The dual mass systems are designed to transmit less engine vibration to the driveline, and give a better more car like driving experience. They also reduce some of the jarring and stress on the transmission and remainder of the drivetrain. They work fine as long as the engine remains unmodified and the vehicle is not used/abused beyond manufacturers recommendations.

As soon as you start to increase the engine power over stock, or load the vehicle beyond design parameters, you run into problems. Dual mass flywheels are tuned systems and must be matched to the engine torque curve, engine resonant characteristics, vehicle load curves (including axle ratio/tire size calculations). They work by having a set of springs inserted between two rotating masses (thus dual mass). The springs are sized to soak up some of the resonant vibration from the diesel engine under load conditions. A dual mass fly wheel generally also contains an over torque friction release, so if it gets suddenly overloaded, rather than damage the springs, it slips. This works fine as a safety valve, but if it does it much it burns up. In short, overloaded they burn up and the springs get destroyed and they are worse than if it were a single mass FW.

The single mass part WILL tend to transmit more engine pulse (vibration) tot he drivetrain, and will seem a bit rougher. But it is straight forward to design a single mass flywheel and clutch package for pretty much any engine torque curve and vehicle loading combo you can come up with. Drives more like a truck, but has much better reliability at extreme use levels.

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After a lengthy discussion with Andy i'm gonna sticknto the dual mass..

Just gotta source one thats going to be most suitable..

Found this little youtube clip for those that on know how it works that makes a little more sence!

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I don't think that's the right choice' date=' but it's your car mate, so go with what you want ;)

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I think I would agree with that also. Unless you can find a dual mass that has been designed to withstand the amount of power you are making which I cant think there is, or if you are worried that your gearbox is the weak link and you would rather the clutch went first.

Would be interesting to learn why Andy has chosen that.

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My understanding of the reason is running this power through the setup has caused crank shafts to dissintigrate on a couple of occasions and by purposely using a DMF as the weak point we should offer a margin of protection to the engine and transmition..

With that reasoning I kind of agree that id rather replace a flywheel and clutch than a total engine rebuild.. :)

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Surely there is a way to make it more reliable?, I mean dissintigrating cranks?, that's crazy at 600 bhp or so surely?, I mean that's not hideous Power, although very nice :-), it would be nice to use the power and not have to rely On a known weakpoint that is surely gonna spoil your fun? ;-), are there any other options mate?

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This has turned into a bit of a clutch discussion but to add my 2 pence worth. The dual mass items are balanced for the power/torque of the engine. Plenty of other cars manage with single mass without destroying the crankshaft. I really can't see an argument for sticking with dual mass in a car like yours but i'll be more than happy to help you tow it back from the Pod.....

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  • 1 month later...

if your planning on keeping the dual mass flywheel you may as well keep the standard clutch as well because trust me you will be spliting your engine and box in no time to fit single mass flywheel because the duel has failed, i see the whole leaving a weak point idea but one that means removing the gearbox may not be wise.

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