Stroke M103 using M104 crankshaft?

[Ortolan]

Also posted in Performance Paddock:

I've been wondering if it would be possible to stroke the stock 3.0L (2962cc) M103 engine using a crankshaft from an M104 engine.
Using the 3.2L 84mm crank would give a displacement of 3101cc.
Using the 3.6L AMG 92.4mm crank would give a displacement of 3411cc.
Can someone tell me if this would be possible. Thanks.

[t walgamuth]

dunno from experience, but you need to consider (and you may already know this) bearing size and width, bearing spacing and rod length. i wouldnt be surprised if it will work as benz tends to carry a lot over from model to model.

sounds like an interesting project.

tom w

[Kestas]

For starters, I'm pretty sure you'd need to replace the connecting rods because of the length issue. Then you'd have to check for interference with the block (bottom of the bore).

But as tom suggested, you may luck out and find many parts are the same. Manufacturers don't like to make design changes to the block, so I can bet the rods will need to be replaced.