Clutch and Flywheel options

[Dippy]

I think my clutch may be starting to go, so I need to decide what to do about it when I need to.

As my car is tuned, I believe it would be sensible for me to get an RS4 clutch instead of an S4 one. I then wonder if it makes sense to upgrade the flywheel at the same time.

So can anyone help with these questions:

1) Is an RS4 clutch my best option or are there others?
2) I am assuming that replacing the flywheel at the same time as doing the clutch will minimise the labour costs involved. Is this true?
3) What are my options for an upgraded flywheel?
4) What are the pros and cons of a lightweight flywheel? How would it affect normal and low-speed driving, and idling?

TIA

[Golich]

I don't think the RS4 clutch is particularly better than the S4 despite the claims. They have been known to go at 25K. Of course this is highly driver dependant. The previous owner of my RS4 had to replace the clutch at 26K and he was adamant it was not due to a change in his driving style from 4 Audis before the RS. Having said that there are plenty of lads with stock clutches running 460bhp and is it 430 ftlbs? So it would seem to be up to the job and certainly of your 340bhp/390ftlbs?

I've heard that Tanagona (spelling?) offer a decent lightened flywheel. Searched the RS4 forum? There has been a lot of chat on this in the past.

Yes - replacing the flywheel at the same time would save you a lot of money!

It has been said that certain lightened flywheels cause a gearbox rattle at idle. Depending on how much weight is shed from the flywheel will affect how easy it is to stall and of course could make the idle lumpy.

I'm of a mixed opinion on it. I looked into this from an overall inertia perspective, in my opinion there is more to be gained in putting a set of lightened alloys on your car if you want to improve acceleration times etc. Ok the engine may rev more freely but still has to put the rest of the car in motion and the standard S4 wheels are incredibly heavy x 4 that 's a lot of inertia to accelerate! However, the weight reduction on the alloys should be based around the rim for maximum effect as Inertia = Mass x radius squared.

How will it effect normal and low speed driving? I guess you need the feed back from someone who has actually fitted a particular flywheel to his car. RS4 forum.

I suppose a lightened flywheel is one of those diminishing return items like air filters and CAT back exhausts. But they all help!

[sitas3]

I had a lightweight flywheel on my S4 and personally I found the rattling noise it generated rather annoying in the lower gears up to 2k revs. The consensus on here was to keep the revs up!

[BlackShadow]

[quote="Golich"]I'm of a mixed opinion on it. I looked into this from an overall inertia perspective, in my opinion there is more to be gained in putting a set of lightened alloys on your car if you want to improve acceleration times etc. Ok the engine may rev more freely but still has to put the rest of the car in motion and the standard S4 wheels are incredibly heavy x 4 that 's a lot of inertia to accelerate! However, the weight reduction on the alloys should be based around the rim for maximum effect as Inertia = Mass x radius squared.

Golich, given your above statement, are there any wheels in particular you would recommend for the S4? A lot of aftermarket stuff seems to be about style not loosing weight viz gaining performance.

[daveweld]

my rs4 had lightweight flywheel already fitted when i bought,
had it for 5 months, detest metalic noise created at low revs
when clutch is u/s i will have dual mass fitted
no problem when in fast mode, but for family/lower rev driving, it is a pain, alternatively turn up stereo to counteract tractor noise
would recommend power upgrades rather than flywheel

[Dippy]

Thanks for the comments. Anyone know why a lightweight flywheel causes this noise?

[ChrisG]

Presumably the heavier flywheel helps to smooth out the firing impulses ?? I can understand that there will be a double benefit with lighter wheels, unsprung weight and less revolving weight. OZ make one
http://www.ozracing.com/eng/car/index.p ... 3&wheel=18# . Hving looked I thought their Superleggera was forged and weighed in at about 16 lbs
BBS have some spun rim versions RC and Challenge I think
http://www.bbsdirect.co.uk
There used to be a wheel weight chart on Audiworld

[smurfbus]

LWFW are one piece vs. stock dual mass. there are springs witch absorb the oscillation and rattling. thats why I upgrated to rs4 combo. if you only install the PP and disk you might end up with slipping clutch unless you have your FW resurfaced.

IIRC superleggeras are not forged. IIRC the 3piece 19in. was forged at least the center part.