Flywheels

[wacomuk]

Originally Posted by Dr Silvia

assuming you're both right, there is either a lot of variation in finished weights, or there's three kilos difference in weight depending on which mk flywheel you have

the fly wheel i weighed was from a mk2 it deffo weighed in at 25lbs heavy fooker

[Dr Silvia]

well 25 pounds = 11.34 Kg's so the confusion still stands... are you 100% on that stock flywheel weight CNHSS??

[PukkaSilvia]

You would expect them to be lighter on the mk2 hopefully. We need to find out 100%

[Dr Silvia]

it would be logical

when adam and i took the flywheel off of my mk1 engine and compared it to the mk2 wheel it was definately different...

without access to the bathroom scales however i didnt get the opportunity to compare on the spot

[adzs12]

Im sure i have a mk1 and 2 flywheel kicking about still so il weigh the 2 when i get a chance I definately remember the difference doc when we compared the 2

[Dr Silvia]

good man

[30psi]

I've got a lightened flywheel (that no one has bought yet).

I remember when I checked, it was 4lbs lighter but thats with bathroom scales which isnt the best way to measure the difference.

You notice the engine is more responsive at idle but it doesnt make a huge difference when driving.

Thay flywheel is pretty expensive and such an item is really only beneficial on something with a fully balanced, knife edged bottom end assembly.

A lightened flywheel doesnt reduce the torque at idle (as most like to believe) it actually reduces its inertia. So if you are clumsy with the clutch you lose the inertia quickly. Its a way of storing energy.

I would only be concerned when using a tight arsed bastard paddle clutch with a light flywheel as you are much more likely to kill the little inertia the flywheel has.

[CNHSS1]

sorry for the confusion, i was relying on my memory regarding the original weight, so you may be right with the 11.5 or 11.34kgs, but the machined weights are correct.

Pukka
sorry for the confusion, my point was more that someone fitting a 4.5kg flywheel in a silvia with std ecu (where it cant be remapped to help the slow running) would make the car a pain in day to day use. My car weighs 750kgs, uses a 9.5kg fly and AP paddle and nismo cover and is crap at anything below 20mph. Luckily its only for moving around the paddock or pits but it does p*ss me right off. Couldnt put up with it in a road car. I would have thought that a heavier car (silvias are 11-1200kgs right?) would be worse still.

As for the fly, it does look the nuts, just wish they did one to suit the ET bolt pattern

[30psi]

Craig, your right the issue comes when driving over speed humps and shit like that where there is slack on the transmission. A nice flywheel dampens this.

A lumpy idle won't be dampened by the flywheel and it will idle worse. On a multi cylinder engine you can get away with it more.

[Dr Silvia]

Originally Posted by 30psi

I've got a lightened flywheel (that no one has bought yet).

arent you using it in that datsun you bought??