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Re: 2002 with an M3 crank?

> What is the stroke on an M3 crank?

84mm, for the standard 2.3 crank.

> Anyone familiar with what is need to put an M3 crank in a 2002?
> What is needed? rods? different timing/oil gears? bearings? flywheel?

The main bearings are the same.  I think the rod bearings are also the
same, although BMW lists a different part number for the M3 bearings.
The main problems to doing this swap:  1) The M3 crank is substantially
heavier, with larger counterweights. 2) The nose of the M3 crank is larger
than the 1.8/2.0 cranks.  This means that the nose of the M3 crank would
need to be cut down, and rethreaded and rekeyed, or you would need the
M3 chain sprocket, crank pulley, nut, and front seal, with the front timing
cover bored out to accept the larger front seal.  I'm not sure the M3
pulley and sprocket will mate up with the 2.0 chain and ancillary equipment.
At least the rear end of the M3 crank is the same as the 1.8/2.0 cranks.

Also, the M3 rods are longer, 144mm vs. 135mm.  The M3 pistons have a much
shorter pin to deck height to compensate.  The M3 bore is 93.4mm, which
is bordering the limit that the standard 89mm 2.0 blocks can be safely bored
out to.  The M3 uses a block with siamesed cylinders.  Also, the dish in 
the M3 piston means that mating it all up with M3 pistons and an 8-valve
head, the compression ends up somewhere around 7:1.

Can you tell I've been researching this?  :) :)

> After my affair with the pistons not getting sold to me, I figured
> I would measure my stroker setup and re-evaluate before I spend $400
> for a new set of pistons.

I've been looking at this, and am not sure that the gain in displacement
from 4mm of stroke would outweigh the increased mass and the trouble and 
expense to make it all work.  Plus, I have a feeling that the resulting 
motor would be more prone to vibrations and buzzing than a 2.0.  
 
> BTW, I don't know if I posted this, but my stroker set up is as
> follows:
> 
> Crank -         88MM
> Rods -          Stock
> piston -        cut down. Yup, stock (Noral) pistons which were
>                 cut down into pop-ups to make up for the stroke.

Cheezy.  Amazing that the pistons are still strong with 4mm taken off of 
the top.

Hope this helps,
Ben