So far my flywheel and crank pulley are standard however I have a Perrin crank pulley to fit which is obviously loads lighter, will this throw the engine balance out in relation to the flywheel?

Also I want to lighten my flywheel but not sure how light to go.

I have heard of differnt weights but which is best.

obviously the lighter the better but is this true or will it get to light and warp.

3.3kg is the lightest I have heard
but also 6kg and 6.3kg

is there a happy medium between all these weights that will complement the lightened crank pulley or will it make no difference front to back?

would 4-5kg be ok or what is the recommended without fear of warping or being to light and breaking under the strain of everyday use?

Cheers

Steve

Speak to Simon at Roger Clark they have a 4.5kg version....

Contact 01455 828610

Hi Wurzel,

Check on the German/Swiss Impreza board - I think Mäcky does lightened OE exchange ones. He also posts on here occasionally.

Richard

Rich

I saw his post on the German bbs, he said it was MY98 flywheels.

about €200

I presume there is no diffrence between a 98 and a 2000 flywheel.

No difference to my knowledge, mail him to confirm. Pavlo also has a new one for sale; http://www.scoobynet.co.uk/bbs/thread.asp?threadid=293833

Richard

i have had no problems with my perrin pulley

Wurzel, I when through all these questions about 4 weeks ago when the box was out. Bought a TEG wheel @ 5.5 Kg.
I was advised not to fit such a light wheel as making strong starts from standstill becomes hard as the flywheel effect is lost.
Seems that a good weight is 8Kg, I think the stock unit is 11Kg.
The guys who race these cars a lot go for the 8 Kg mark.
There are one or two for sale on this web, Pavlo's is new too for a demon price!
Graham.

Cheers Chaps

Yeah...don't fit a light flywheel :) ....you might get hooked to it .... Especially the Fidanza aluminium ones..only 4.3 kilo,
it's so annoying to feel this great acceleration out of tight corners, the throttle response is so quick...you just don't want it ......even braking gets easier..what's the fun in that ?
Just leave to the stock one and never feel what I do ....
if you're ever around in the south of Holland, pop over and I'll show you what you don't want ;) ;)

Standar is around 12 kg and this will machine down to under 8kg quite easily and is a good all round weight. I have a light RCMS, around 5kg from memory and there is no problem with tick over but nor could I feel any measurable performance difference. What I did notice was that drag start launches had to be far more accurate as I no longer had the inertia and hence tolerance of the 8kg flywheel.

Careful with lightening cast flywheels they have a habit of coming to bits and having your ankles - after they've had your clutch housing, starter, gearbox input shaft and so on. Not a pretty sight.

We had an engine came to us off a Skyline, with a flywheel that came to bits at the Nurburgring. Seriously there was nothing l MEAN NOTHING between cylinder No. 5 and 4th gear !!! the bits of flywheel came out the top of the dash and broke the windscreen. One lucky guy to still have feet.

David API

Exactly, ask Don Garlits, drag racer in the usa....
Graham

My machine shop refused to take my stock flywheel below 8kg on safety grounds :)

Richard

Power Station can supply an American made good quality aluminium flywheel which weighs 4 Kg. I am very happy with it-certain makes it sparkle on the acceleration front and has been no problem at all. The idle is just as smooth as before, you just have to allow for the lower flywheel inertia when you engage the clutch. Don't even notice that side anymore.

Les :)

I'm sure many are happy with a light f/wheel, but in competition such as drag racing, getting off the start is closr to an art form if want to be consistant. The mass of the wheel makes for consistancy, too light and it is easy to bog down, you can't get wheel slip (as opposed to wheel spin)and get absolute max traction and stay in the power band. I've driven a friend's RA with a 5kg wheel, and getting the very best start is really tricky, but great when going!
Take your choice!
911

I have a 6.6 kg IIRC STi flywheel from Roger Clark and it is great, just +100 RPM so it idles at 850 RPM and it runs nicely at stoich. Revs nicely and doesn't bog on the 2.5, with a 2.0 it might be a bit light?

The Lateral flywheel I had was of similar weight but needed 1000 RPM to idle smoothly at stoich on the 2.5, although it may have been due to the gearbox and clutch since they were also changed at the same time, and unbalanced rotating mass could make it rough.

I can't change idle ignition timing, that may make a difference in getting a smooth idle with lightened components.

Also injector nozzle type at least with JECS makes a difference - disc far superior to pintle on my engine and ECU anyway.