Flywheel Materials

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Discussion

Corb

Original Poster:

29 posts

231 months

Wednesday 6th July 2005
quotequote all
At the moment on my 2.0 Turbo Corsa, I've got a cast iron(i beleive!) flywheel from an Astra GTE 16v which has been lightened and balanced. I spoke to Helix Autosport today, and he suggested, from the two different materials of clutch they produce to fit my car, steel and aluminium, I opt for an ally one. He said the fly ive got on at the moment wont cope with the torque im going to be throwing at it and will just crack and break.

Now, a friend has pointed out to me that aluminium is a softer metal and has a lower melting point, so is less resiliant to heat. This being the case, why has Terry at Helix suggested to me the ally fly over their steel one?

The reason I phoned them in the first place was I was after a paddle clutch friction plate on its own, to replace my standard, slipping one i have on there, then got all tangled up into talking uprated fly's, covers and one of their bearings aswell as the paddle friction plate!

Any help here guys would be greatly appreciated. I ask here as the corsa websites are packed with know-nothing goons who make pointless replies!

Thanks

Corb.

deltafox

3,839 posts

233 months

Wednesday 6th July 2005
quotequote all
The lightened flywheel is most likely cast iron as you surmise, and as such isnt likely to be too good for your long term health if it lets go at 6000 rpm!

The alloy flywheel has a steel insert to act as a friction surface.

Aluminium may well have a lower melting point than steel, but believe me, you aint never gonna melt it.
Its sheer size/mass will conduct heat away so quickly itll never ever get anywhere near its melting point.
Its also safer than a cast iron item as its got a whole lot less inertia at speed, its softer than cast and as its lighter, youll get good spin up when you go for it off of the lights.. and itll be faster through the gears leading to a better acceleration.....

Ps, change the flywheel sooner rather than later; Ive seen the results of an exploding flywheel and its like a bombs gone off inside the car, and the guy lost both feet!



>> Edited by deltafox on Wednesday 6th July 20:22

Corb

Original Poster:

29 posts

231 months

Wednesday 6th July 2005
quotequote all
shiiiiiiiiiiiiiiiiiiiiiiiiit!

The car's actually off the road now anyway at my mates house cos of the clutch. If its broken, I wont drive it!

This is the bill Terry gave me on the phone

3.4 Kg Aluminium Flywheel - £270.82 + VAT
Uprated Clutch Cover Plate - £186.74 + VAT
Paddle Clutch Plate - £147.65 + VAT
One of Their Release Bearings - £17.13 + VAT

£720 ish all in. Thats one expensive drivetrain. Especially after i only got the lightened fly, 6-speed box and Quaife LSD fitted last Wednesday along with some new seats which never made it into the car yet! I think I need to win the lottery

deltafox

3,839 posts

233 months

Wednesday 6th July 2005
quotequote all
Sounds like a good package to me....but the paddle clutch will likely be a pig in the traffic! Enjoy!

Boosted LS1

21,188 posts

261 months

Wednesday 6th July 2005
quotequote all
deltafox said:
Sounds like a good package to me....but the paddle clutch will likely be a pig in the traffic! Enjoy!


Especially in a long traffic jam on a hot day going up hill!

apache

39,731 posts

285 months

Wednesday 6th July 2005
quotequote all
deltafox said:

Ps, change the flywheel sooner rather than later; Ive seen the results of an exploding flywheel and its like a bombs gone off inside the car, and the guy lost both feet!







hells teeth, does that happen often in these things?

Boosted LS1

21,188 posts

261 months

Wednesday 6th July 2005
quotequote all
Not often, probably quite rare for road cars but look at the blankets used on drag cars which are there to catch exploding flywheels that rip right through the bell housings!

It can happen and if it does a sheet metal floor won't stop parts getting into the safety cell of a normal car. I'd never take a lot of metal off a stock flywheel.

Boosted.

deltafox

3,839 posts

233 months

Thursday 7th July 2005
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Boosted LS1 said:
Not often, probably quite rare for road cars but look at the blankets used on drag cars which are there to catch exploding flywheels that rip right through the bell housings!

It can happen and if it does a sheet metal floor won't stop parts getting into the safety cell of a normal car. I'd never take a lot of metal off a stock flywheel.

Boosted.


Had the one on the golf done some time ago; its the very very heavy VR6/corrado item that has a huge ring of material on the outer rim of the flywheel.
Although its been done correctly,ie; material removed only from the outer edge, im not happy with it being on an engine that can accelerate like the golfs does and will soon have an aluminium flywheel sourced for peace of mind.

Boosted LS1

21,188 posts

261 months

Thursday 7th July 2005
quotequote all
deltafox said:

Boosted LS1 said:
Not often, probably quite rare for road cars but look at the blankets used on drag cars which are there to catch exploding flywheels that rip right through the bell housings!

It can happen and if it does a sheet metal floor won't stop parts getting into the safety cell of a normal car. I'd never take a lot of metal off a stock flywheel.

Boosted.



Had the one on the golf done some time ago; its the very very heavy VR6/corrado item that has a huge ring of material on the outer rim of the flywheel.
Although its been done correctly,ie; material removed only from the outer edge, im not happy with it being on an engine that can accelerate like the golfs does and will soon have an aluminium flywheel sourced for peace of mind.


Is this a flywheel that's quite thin near the centre and thicker around the edge? If so I know the type and yes I agree with you. Thick socks & trousers won't help if it fails.. I saw a flywheel like this on a chevy boat engine, ugly springs to mind.

Boosted.

deltafox

3,839 posts

233 months

Thursday 7th July 2005
quotequote all
Yeah. If you were to cut it down the middle and look at it in cross section it look like a "[" with very thick outer edges.
I had all that material removed so it weighed around 20 pounds from the original 30 ish.
Still, not happy so will get it replaced soon and should spin up like a good un after that.

love machine

7,609 posts

236 months

Thursday 7th July 2005
quotequote all
Mini saloon car racing in the 60's was legendary for exploding flywheels, personally having one pointing at me, I'm good mind to make up a big piece of plate for the job. I would watch the alloy flywheels for corrosion/crystallisation like an old wheel... I think the best option is one cut out of an EN16 billet and lightened right. I suppose alloy would carry less momentum when flying but is more prone to faulting than steel.

It's one of those things which is so important to be done right. I considered lightening a flywheel myself and then I thought about my feet.....

deltafox

3,839 posts

233 months

kenmorton

271 posts

251 months

Thursday 7th July 2005
quotequote all
You could also try www.superclutch.co.uk
The website seems to be having an overhall at the moment but there is an email link on there.