Found this article on advantages of lightening the flywheel, on a VW-related site.

These include faster revving, faster acceleration secondary to an equivalent effect of dropping 70-100lbs of weight from the car...Lightening

Hope to post a review of life with a Helix steel SMF when (or if?) I'm finally done with my DIY clutch fitting...

Cheers

Bas

Flywheel=mass, hence moving it=inertia. Therefore lightening it gives better revving (and hence acceleration). Downside is rougher running - the flywheel is there in the first place to smooth out the pulses from cylinders firing twice per revolution (in a 4 pot).

searching about - the rougher running gives the well-known clatter in the drivetrain at idle with the clutch out.

People have found that by adapting the ECU to run the idle speed a tad faster and/or by using a heavier gearbox oil they can minimalise it. This is by getting the idle up to where the pulses are too fast to cause a harmonic shudder and by allowing the drivetrain insides to be somewhat cushioned from vibration by the heavier oil.

Will find out first hand how bad it is, but having happily lived with solid lifters + aggressive cam on a V-8, don't think that this is going to be any problem.... When someone points out that it doesn't sound right, they look decidedly uncool when you tell them that's the way a modded part is supposed to sound...

Cheers

Bas

"Don't forget that changing flywheels requires you to re-set the endplay"

Why?

Nice find tho' Bas

i'm going to be having a flywheel lightened in the near future...

i will post up some before and after pics of it too

B!oody good article!!!

I have ordered an aluminium SMF for my car from Impossible, all being well it'll be fitted there early June....along with my 6 speed!!

Found this article on advantages of lightening the flywheel, on a VW-related site.

These include faster revving, faster acceleration secondary to an equivalent effect of dropping 70-100lbs of weight from the car...

As I understand the article, the 70-100lbs figure quoted is only the effect in first gear. As it says in the article "The benefits decrease in higher gears in proportion to whatever the ratio is". I don't claim to have followed the maths, but it makes sense - in lower gears the engine builds revs a lot faster, so the inertia of the flywheel is more significant. By the time you get to higher gears the (geared) weight of the car is more significant than the flywheel weight which is the same in every gear.

So it seems it's not an across-the-board effect on acceleration.

You're absolutely right to point that out mate. So far, I have found that the SMF makes the car literally leap out at roundabouts and the turbo seems to spool up faster perhaps.

Since the real weakness of the Fab vRS is 0-60 acceleration, the SMF should make a difference here. May have to see if I can get a slot on the timed dragstrip at the Bahrain F1 circuit.

Another 200km of bedding-in left to go and then I'll get a proper idea as to the performance side of this setup and will post a small review and my personal opinion.....

Flywheel=mass, hence moving it=inertia. Therefore lightening it gives better revving (and hence acceleration). Downside is rougher running - the flywheel is there in the first place to smooth out the pulses from cylinders firing twice per revolution (in a 4 pot).

Interesting. The Civic Type-R in 01-03 had a heavier flywheel, than the one's in 04-06. Which makes the times to certain speeds drop etc.

So, In theory, my car would be quicker to 100 and beyond, than an 02 model for instance as it rev's quicker and crisper.

But, another reason why they changed to a lightened flywheel, was to improve jerkiness and smoother running.