Flywheel Thickness

[Tarek80]

Hi all,
I need some help determining if the flywheel out of 1988 325i Vert can be resurfaced or not.
The one I took out is single Mass flywheel. I measured the thickness and it came to 31.29 mm. The Bentley shows minimum thickness of 32 mm for 6 cylinder engines from 1985 - 1990. No mention if that for Single or Dual mass flywheels.
I Contacted IE Engineering and asked about the minimum thickness they require for their Flywheel service, the guy at the machine shop said my flywheel should be fine.
I also contacted RHD engineering and asked them about the thickness of their lightened Flywheel, the told me that the thickness is 24 mm from Flange to Top of friction surface. ( when I measured mine it was 25.89 mm ). They also mentioned that the thickness of the friction plate is 9mm on their flywheel ( when I measured mine From top of the toothed ring to top of the friction surface it was close to 13 mm).
This is my weekend car and I don't see the need to upgrade the flywheel if I can resurface the one I have.
Thank you all your help!

[DanThe]

They can most definitely be resurfaced, ideally ground rather than turned, there is plenty of material to go at but you must make sure the friction surface is the correct height in relation to the clutch cover mounting surface. I do a flywheel lighten and recondition service too -

[martauto]

Just a question Dan, why not turn the fly wheel surface ?
With turning you can achieve any surface finish you require and will be quicker and cheaper too, just curious mate.

Mart.

[DanThe]

It just gives a better surface, flatter than what most lathe operators can achieve

[Tarek80]

Thank you Dan
Very useful information.
Unfortunately, I live in the Middle of the US where maybe a handful of E30s exist. And don't really trust my local machine shops.
What is the correct height in relation to the clutch cover mounting surface? I saw a .3mm on some forums. Bentley doesn't mention that either, just says there should be a little clearance.

[martauto]

It just gives a better surface, flatter than what most lathe operators can achieve

What type of surface are you looking for Dan ?
Is it grip or smooth as possible ?
Most CNC`s and "good" center lathe`s can achieve "micron`s" in size and surface finish is down to what you require.
What type of grinding are you talking about ?

Mart.

[Tarek80]

Hi,
Anyone knows What is the correct height in relation to the clutch cover mounting surface? I saw a .3mm on some forums. Bentley doesn't mention that either, just says there should be a little clearance.
Thanks!!