flywheel weight

[p fandango]

i've got a flywheel i'm just about to get lightened. Standard weight is 8.5kg, but what weight do i get it took down to? Does anyone know the normal weight of the TTV flywheels

[Alan M]

If its machined proportionally quite a bit of material can be removed. You still want some weight there so going to far would be unwanted. I would take 1.5kg to max of 2kg depending on the weight of the car.

[p fandango]

If its machined proportionally quite a bit of material can be removed. You still want some weight there so going to far would be unwanted. I would take 1.5kg to max of 2kg depending on the weight of the car.

its for BT, so not much car weight to go with it lol

[M-R-P]

its for BT, so not much car weight to go with it lol

Probably gonna end up looking like this....

[p fandango]

Probably gonna end up looking like this....

still got a bit more metal i can shave down on that tbh Martin lol

[jardon]

http://kalmar-union.com/parts/volvo-...-transmission/

That's what I use. Pros - revs properly and much quicker through the gears. The stock dmf is slow to lose momentum. Cons - gearbox chatter due to reduced damping of vibes (not audible in car).

Overall suits me and significantly cheaper than a dmf to boot. I suspect the cerametallic clutch will last longer than the flywheel but time will tell. With your motor it will make less difference as the stock smf is lighter than my dmf. If it's a race only application then I would go as light as is safely possible - take advice from somebody who has experience of light flywheels and quarter mile competition.

[Volvostorm]

I've had about 1.5kgs taken off my flywheel too.

[p fandango]

http://kalmar-union.com/parts/volvo-...-transmission/

That's what I use. Pros - revs properly and much quicker through the gears. The stock dmf is slow to lose momentum. Cons - gearbox chatter due to reduced damping of vibes (not audible in car).

Overall suits me and significantly cheaper than a dmf to boot. I suspect the cerametallic clutch will last longer than the flywheel but time will tell. With your motor it will make less difference as the stock smf is lighter than my dmf. If it's a race only application then I would go as light as is safely possible - take advice from somebody who has experience of light flywheels and quarter mile competition.

thats 1.75kg lighter than standard SMF, its not full race only i'm going for but quite happy to compromise the on-road drive for a decent improvement. The engineering shop i'm going to make engines for a few rally teams so see what they recommend

[p fandango]

I've had about 1.5kgs taken off my flywheel too.

i'm thinking of going for 2kg off, just to make it a nice round number lol.

[jardon]

thats 1.75kg lighter than standard SMF, its not full race only i'm going for but quite happy to compromise the on-road drive for a decent improvement. The engineering shop i'm going to make engines for a few rally teams so see what they recommend

Sounds like a plan. Just seen your 2kg off post - that would be comparable with mine and should be perfectly driveable on road. As you are no doubt aware shaving off rotational mass has a significantly greater effect on acceleration than losing the same weight from the body, etc - more noticeable in lower gears.

[Engineer]

The billet steel flywheels from Kalmar Union for non duel mass flywheel clutches as on 850's only weigh 5.3 kg, I doubt you will get a cast iron/cast steel flywheel down to this and be able to guarantee it won't explode at high rpm, but don't let that stop you who knows you might be ok

Here's a pic of my billet one fitted.

Its also worth remembering that billet steel is harder than cast iron and cast steel so should see the clutch disc finish second as regards wear etc.

[jardon]

Its also worth remembering that billet steel is harder than cast iron and cast steel so should see the clutch disc finish second as regards wear etc.

Didn't know that. For some reason I thought steel was softer and that my nasty clutch would eat it.

[Niles]

I've been told by a race engineer DO NOT SHAVE DOWN A CAST IRON FLYWHEEL!! He was very firm on his comments and stuck to it. He said cast iron will not like a shave and very VERY likekly to go pop at high rev's.
Is that just him or has anyone an idea that it WILL be safe to remove 1.75kg's off a standard SMF?

[p fandango]

The billet steel flywheels from Kalmar Union for non duel mass flywheel clutches as on 850's only weigh 5.3 kg, I doubt you will get a cast iron/cast steel flywheel down to this and be able to guarantee it won't explode at high rpm, but don't let that stop you who knows you might be ok

i've just been looking on the TTV website, 3.5kg here we come lol. When i dropped mine in he explained there was only so much he can take off, got to keep it a certain thickness to stop the risk of explosion

[p fandango]

I've been told by a race engineer DO NOT SHAVE DOWN A CAST IRON FLYWHEEL!! He was very firm on his comments and stuck to it. He said cast iron will not like a shave and very VERY likekly to go pop at high rev's.
Is that just him or has anyone an idea that it WILL be safe to remove 1.75kg's off a standard SMF?

the machine shop who's doing the work make complete rally engines from scratch so sure they know what there doing, isn't the face machined flat during manufacture

they also offered to make a complete new flywheel from a lighter material, daren't ask how much they want for that lol

[t5_monkey]

There's some alarming videos of flywheels exploding on you-tube.

With that much spinning metal, I'd be tempted to buy a new lightweight one.

[p fandango]

There's some alarming videos of flywheels exploding on you-tube.

With that much spinning metal, I'd be tempted to buy a new lightweight one.

some painful one's as well if the bits went off in the wrong direction, the bulkhead would be like tissue paper compared to shrapnel from that lol. They know what there doing

[jardon]

There's some alarming videos of flywheels exploding on you-tube.

With that much spinning metal, I'd be tempted to buy a new lightweight one.

+1 shaving that cast iron one does sound a bit iffy

[endo-t5]

I know someone who had a mini flywheel shear and come through the bulkhead during racing hence he then added a 6 mm steel plate to bulkhead to save his life but not as bad as cosworth 4x4 as they can break front prop if driven hard from cold guy broke both his legs when it snapped as he had 400 bhp doing high speed runs at brunters.
don't forget may spin up faster but you'll lose some torque with the lighter flywheel

[p fandango]

don't forget may spin up faster but you'll lose some torque with the lighter flywheel

with the car being lighter losing a bit of torque won't be a problem, my god i might as well buy a Honda lol