[Nicky92]

I ordered the Stage 3+ kit off ebay and the flywheel off LMPerformance.

I got the flywheel today and it was 25 lbs and a dual mass flywheel. I was going under the assumption that I ordered a Single mass and have been watching chatter videos all week.

My question is, Will my car benefit THAT MUCH more with a single mass, over the Spec 25lb dual mass flywheel??? (Stock is 28lbs)

I am not too excited for chatter, but I also want the most performance I can get, kind of a gray area here ya know.

[Kabnine]

I think you will find the reason people replace the flywheel isn't it's weight. I am replacing mine because there have been a few people who have had problems with them at high horsepower levels. Some with codes being thrown, others where the flywheel has come apart. My DMFW was taken off the car yesterday and the mechanic has reported that it wasn't in very good condition and in his opinion it was at the stage where if could have come apart in a catastrophic way.

[Miller335]

I agree.

I think we all would run a DMFW in a BMW if it didn't cause the reported misfire/knock/timing issues nearing 500whp.

[Nicky92]

So what you're saying is, Do Single mass right?

I am close to 450whp, so I should do the right thing here right?

[Miller335]

Originally Posted by Nicky92

So what you're saying is, Do Single mass right?

I am close to 450whp, so I should do the right thing here right?

Not really.
If you think you'll always stay with OEM turbos then stay dmfw.
If you want to go RB's, single turbo etc at some point then go smfw.

At least that's how I look at it. Please some correct me if I'm wrong, in the same boat.

[Nicky92]

Ok weird mixup. I think I actually have a single mass flywheel. I got super confused

This is what it looks like...

[brusk]

The only reasons for replacing a DMFW that I know of are:
1. Stock is worn out and you found a SMFW cheaper
2. You are making over 600HP, that's when the knock issues arise not 500.
3. Your afraid the DMFW might fly apart and cut your feet off, no feet casualties yet but a small number of flywheels blowing apart or about to.

I honesty thing most people that run stock frame turbo's would be fine with a new DMFW and the 550i clutch that is being sold as an upgrade. Only a few people that have tried it and it has about the same pedal pressure with a little extra holding power.

The Steel Spec SMFW's are only 3 lb's lighter than stock so no benefits there and the SMFW's chatter, especially with the AC on.

[blaster3500]

That is a SMF. Just make sure you got the steel. The only company that makes the DMF is LUK and are the OEM

[froop]

Originally Posted by brusk

The only reasons for replacing a DMFW that I know of are:
1. Stock is worn out and you found a SMFW cheaper
2. You are making over 600HP, that's when the knock issues arise not 500.
3. Your afraid the DMFW might fly apart and cut your feet off, no feet casualties yet but a small number of flywheels blowing apart or about to.

I honesty thing most people that run stock frame turbo's would be fine with a new DMFW and the 550i clutch that is being sold as an upgrade. Only a few people that have tried it and it has about the same pedal pressure with a little extra holding power.

The Steel Spec SMFW's are only 3 lb's lighter than stock so no benefits there and the SMFW's chatter, especially with the AC on.

Incorrect. It is 500hp. I have RBs and with a "conservative" tune dyno'd at 350rwkw on a mainline dyno I get the misfiring in cylinders 5 and 6. Coils and plugs are new.

[Nicky92]

Originally Posted by brusk

The only reasons for replacing a DMFW that I know of are:
1. Stock is worn out and you found a SMFW cheaper
2. You are making over 600HP, that's when the knock issues arise not 500.
3. Your afraid the DMFW might fly apart and cut your feet off, no feet casualties yet but a small number of flywheels blowing apart or about to.

I honesty thing most people that run stock frame turbo's would be fine with a new DMFW and the 550i clutch that is being sold as an upgrade. Only a few people that have tried it and it has about the same pedal pressure with a little extra holding power.

The Steel Spec SMFW's are only 3 lb's lighter than stock so no benefits there and the SMFW's chatter, especially with the AC on.

The steel flywheel is 22 lbs. I heard the stock one is 28 lbs? One guy even posted the stock flywheel was 34 lbs but I'm not sure about that.

I thought it would be much lighter than stock. I do plan to go 600+ this winter build.

I should honestly go DMFW because of chatter and stuff..but id rather the performance...

Oh well, thanks for the help guys

[brusk]

Originally Posted by froop

Incorrect. It is 500hp. I have RBs and with a "conservative" tune dyno'd at 350rwkw on a mainline dyno I get the misfiring in cylinders 5 and 6. Coils and plugs are new.

My guess would be the DMFW needed replaced anyway. There's been plenty of other 500HP N54's out there with out issues.


As for the weights I can't remember the exact weights but either the flywheel or the entire flywheel/clutch assembly was only 3 lb's lighter than the OEM stuff. Maybe it was everything as I'm thinking it was like 45lb vs 42lb.

[Jeff@TopGearSolutions]

Lots of misconcpetions and misunderstandings in this thread.

First and foremost there is no reason to get a Spec 3+ clutch and use a DMFW because if you are making enough power to need a 3+ then you must go to a SMFW because the DMFW becomes imbalanced at those power levels.

Second, if one were to purchase any Spec clutch designed for a DMFW they do make an aluminum or steel version replacement. That replacement can also be used instead buying them OEM DMFW or LUK.

Thirdly, if anyone is considering resurfacing their DMFW, dont, I've had a handful of customers try this and they ended up buying a second set of clutch and flywheel because of the problems that occurred. It is very hard to find a shop that can resurface DMFW correctly and have them balanced too.

If you plan on staying with stock turbo's then stay with the DMFW, there is no reason to go to a single mass and it has its drawback of chatter as well.

After 500WHP you will want to go with a SMFW

In regards to aluminum VS Steel, stay with the steel options, the aluminum chatters much more and the steel will hold the torque better because it's heavier.

Last but not least if you find yourself shopping on ebay, feel free to drop us a line if you prefer shopping with the vendors here, we'd be happy to look into price matching if they should have a lesser price and more importantly we can offer advice since we are proficient with the platform.

[Jeff@TopGearSolutions]

Originally Posted by Kabnine

I think you will find the reason people replace the flywheel isn't it's weight. I am replacing mine because there have been a few people who have had problems with them at high horsepower levels. Some with codes being thrown, others where the flywheel has come apart. My DMFW was taken off the car yesterday and the mechanic has reported that it wasn't in very good condition and in his opinion it was at the stage where if could have come apart in a catastrophic way.

This is excellent feedback and something worth quoting as people don't always think full circle when it comes to replacing parts and why they should.

[atx335]

I remember when VF Engineering released their "whisper quiet" LWFW. I ordered their clutch and LWFW and man the change from DM to SM was just too much of an increase in chatter for me. This was on the MK4 R32 so I would be curious what it is like on the e90. Videos were no help, you can "feel" the chatter.

[Nicky92]

Originally Posted by Jeff@TopGearSolutions

Lots of misconcpetions and misunderstandings in this thread.

First and foremost there is no reason to get a Spec 3+ clutch and use a DMFW because if you are making enough power to need a 3+ then you must go to a SMFW because the DMFW becomes imbalanced at those power levels.

Second, if one were to purchase any Spec clutch designed for a DMFW they do make an aluminum or steel version replacement. That replacement can also be used instead buying them OEM DMFW or LUK.

Thirdly, if anyone is considering resurfacing their DMFW, dont, I've had a handful of customers try this and they ended up buying a second set of clutch and flywheel because of the problems that occurred. It is very hard to find a shop that can resurface DMFW correctly and have them balanced too.

If you plan on staying with stock turbo's then stay with the DMFW, there is no reason to go to a single mass and it has its drawback of chatter as well.

After 500WHP you will want to go with a SMFW

In regards to aluminum VS Steel, stay with the steel options, the aluminum chatters much more and the steel will hold the torque better because it's heavier.

Last but not least if you find yourself shopping on ebay, feel free to drop us a line if you prefer shopping with the vendors here, we'd be happy to look into price matching if they should have a lesser price and more importantly we can offer advice since we are proficient with the platform.

Great comment Jeff. Thank you. I appreciate the time you took to explain some things.