Standard 2.5 flywheel question

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rob_htid
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Thu May 06, 2010 9:40 am

What is the thickness of the standard m20b25 flywheel?

Thanks rob
m_jermyn
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Thu May 06, 2010 9:53 am

Its altleast a inch mate and the one a got from a 323i weighed 8.6kgs now it weighs 6.3kgs
rob_htid
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Thu May 06, 2010 9:56 am

I need an exact measurement as a think some berk has lightens my flywheel off the front!!
Tedswagon
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Thu May 06, 2010 9:58 am

I have heard (even though some people will go to less) 6.3 is the lightest you should go to ensure you are not going to undermine the strength of the wheel.

I could be wrong but that is what I have read on other threads. I would seriously consider getting mine lightened.
E30 316i auto coupe build thread here viewtopic.php?f=25&t=273035
rob_htid
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Thu May 06, 2010 10:02 am

Yes I k ow that but it should be lightens off the back... This one has been taken
off the front meaning my clutch may not even touch the fy when pressed! I just need to know the thickness of the fly to see how much has been taken off and weather it is still useable

thanks
m_jermyn
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Thu May 06, 2010 11:59 am

Standard flywheel I know its wrong side but gives you a idea
Image

Lightened the same flywheel
Image

And the clutch side of flywheel... I dont see how you can take weight out of this side as there is the locating tabs for the pressure plate on it.. Does your clutch side look at all like this?
Image

Where did you get the flywheel from? Was it out of another motor? Was it running?

Mike
rob_htid
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Thu May 06, 2010 12:25 pm

The pegs have been taken out and it has had an extensive stepd skim by a nob in a local machine shop! Does nobody have a flywheel they could just measure the with of please from the teeth to the clutch face?

Thanks rob
m_jermyn
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Thu May 06, 2010 12:37 pm

Well I can measure mine tomorrow for you as its 9:40pm here
ricey46
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Thu May 06, 2010 1:06 pm

I had the face of my flywheel skimmed so that there wasn't any high spots, but the datum face was redone on mine so that it is as good as original. I had mine lightned at the same time.

As long as the face is flat and in good condition, it doesn't matter what the original thickness was, as long as it looks like the bottom picture above you're fine. you'll be able to tell if you bolt the clutch to the flywheel. Also just out of interest is it the correct clutch???
Paul.
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