Dual mass flywheel?

[Robz3sport]

Ordering a clutch for my 2001 2.2i Z3, when I enter the reg number it tells me that my car has a dual mass flywheel? Is this so? Do all z3's have these as standard?

 

[Lee]

Hi Rob,

Yes all Z3's have duel mass flywheels as standard.

 

[NZ00Z3]

Yes all Z3's have a dual mass flywheel. Not sure about the Z3M's, so don't quote me for them.

The duel mass flywheel has a thin clutch side metal piece that can not be skimmed/resurfaced as you would do with a single mass flywheel.

It's normal to replace the duel mass flywheel when you replace the clutch, as it is not likely to last the life of two clutches.

If you want to assess the condition of the duel mass flywheel for reusability, look at:
- The surface of the clutch side. Scrapes and starches. Also look for black/blue hot spots. These hot spots cause shudder/judder.
- The amount of rotation between the 2 masses. Lock the crank side mass with the flywheel lock pin that comes through from the engine side. Grab the clutch side mass and see how much rotational movement you have. If you have more than 15 degrees of movement, then the flywheel is out of reusable spec and should be replaced. Count the teeth on the starter ring, these equaled 360 degrees. Do the math to see how many teeth equals 15 degrees. Set up a start point and counted the number of teeth that rotated past it.

The attached phot is the duel mass flywheel off my 2.0L Z3 at around 99,000 miles. It had a shudder/judder. You can see the hot spots that caused the problem. It also had greater then 15 degrees of rotational movement, so was replaced.

 

[Pingu]

Standard Ms have DMFs.

 

[Robz3sport]

Thanks for the replies......flywheel now ordered too.

 

[t-tony]

When Ford brought out the “new“ Transit in 2000 they were fitted with DMF, however it didn’t take long before SMF conversions were offered as a cheaper and far less troublesome alternative. Just because it was initially fitted with one doesn’t mean it has to stay that way.

Tony.

 

[Lee]

Agree Tony. I have a single mass fitted to mine which is lighter (14.5kg down to 9.0kg) then an upgraded clutch disc for all the track abuse.

 

[Pingu]

Agree Tony. I have a single mass fitted to mine which is lighter (14.5kg down to 9.0kg) then an upgraded clutch disc for all the track abuse.

A lightened flywheel isn't about the weight, it's about how that weight is distributed. I've known a lightened flywheel that was actually heavier than standard .

A single mass, lightened flywheel with braided hose is probably as good as you can get at a reasonable budget.

 

[Lee]

A lightened flywheel isn't about the weight, it's about how that weight is distributed. I've known a lightened flywheel that was actually heavier than standard .

A single mass, lightened flywheel with braided hose is probably as good as you can get at a reasonable budget.

That don't make much sense to me, it's all about the weight... I have a lighter fly to allow the engine to rev more freely, the standard fly is really heavy. Also remove the clutch delay valve that really allows you more control over the clutch delivery.

 

[t-tony]

I have not seen a SMF which was heavier than a DMF , and I have fitted a good few.

Tony.

 

[t-tony]

This was a project which Richard, @Zedonist was doing on his 1.9 Z3 before he left the forum a few years ago. Never did get to see how it turned out, he was working abroad and had to turn the car over to his local garage to complete IIRC.

Tony.

 

[NZ00Z3]

I understand what @Pingu is on about. It's all to do with rotational inertia. If the mass is at the outer radius, then you have more rotational inertia.

Two single mass flywheels that weigh the same but of different designs with the mass spread differently will have different rotational inertia. The one with the mass concentrated nearer the center will be better for faster acceleration.

There is a Youtube video somewhere that talks about this. Could not find it quickly to provide a link.

 

[Lee]

I understand what @Pingu is on about. It's all to do with rotational inertia. If the mass is at the outer radius, then you have more rotational inertia.

Two single mass flywheels that weigh the same but of different designs with the mass spread differently will have different rotational inertia. The one with the mass concentrated nearer the center will be better for faster acceleration.

There is a Youtube video somewhere that talks about this. Could not find it quickly to provide a link.

I understand this concept but just not sure how it applies to this thread.

 

[Synclare]

.

 

[Pingu]

Were DMF's not something to do with controlling crankshaft tortional vibration? I seem to recall stories of crank failure following replacement of DMF's with a SMF in some applications.

Could be. It will reduce it. I do know that the immediate effect of going to an SMF is more chatter in the gearbox caused by torsional vibration.

You are definitely taking a risk fitting one, but the rewards are worth it for performance. So far .

 

[Robz3sport]

Think I'll stick with the Dmf.......

 

[Robz3sport]

Clutch and flywheel are bought.........now the fun starts......!

 

[gookah]

DMF or SMF?

 

[jonco]

This was a project which Richard, @Zedonist was doing on his 1.9 Z3 before he left the forum a few years ago. Never did get to see how it turned out, he was working abroad and had to turn the car over to his local garage to complete IIRC.

Tony.

This one I think Tony https://zroadster.org/threads/m44-dual-mass-to-single-mass-and-beyond.6167/

 

[t-tony]

That’s the one Colin, thank you.

Tony.