you looking for one to be sent to you or going to supply your own? what weight too? i know hes getting it down to about 4.6kg now but thats crazy light!
Does he have any experience in flywheels?
Or just a dude with a lathe?
Under 5 Kgs on a cast flywheel sounds light...and possibly dangerously light.
I wouldn't fancy going too far and having it let go...the gearbox casing and firewall won't offer much protection if it does.
Anyone can spin it down on a lathe, but to do it properly you need to balance it afterwards....
As Ess said just a dude with a lathe?
Castings are much safer to machine down as the "grain" is not cut across or weakened like billet steel, but you need to know where to remove the metal to keep it safe.
A car with loads of power and torque does not really want to be that light as the weight and torque will help you pull a higher gear, an 8 or 16v golf will benefit and feel a bit quicker
