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Ferret
04-18-2008, 03:02 AM
Ok, so I was bord and look up the specs on my eninge and the other m50 varriations. Mine is a M50B25, 84mm bore and 75 mm stroke. The M52B28 (used in e36 and e46 328i) has 84mm stroke, could this crank fit in my car? Would this be a good way to increse stroke? Anyone tried this?

Also, I'm taking this information from wikipedia, so if it is incorrect PLEASE correct me!

Thinking about this logically:

B25 75mm
B28 84mm

This means that there's a difference of 9mm, meaing the piston is going to have a lower reach of -4.5mm and an upper reach of +4.5mm - bang goes your head.

If the pistons are the same bore, use the B28 ones with the B28 crank - however if the pistons are a different bore you may get away with just swapping the con rods over...

Just changing the crank may well cause interference problems!

You may need an ECU re-map as well once you're done ;)

Ferret
04-18-2008, 03:15 AM
Just done some research on this - they're both 84mm bores, however you'd have to match them up as they have two factory sizes- just under and just over 84mm.

I seem to remember this is called getting the engine 'bored and stroked' or something like that.

healtoeit
04-18-2008, 09:59 AM
Ok, so I was bord and look up the specs on my eninge and the other m50 varriations. Mine is a M50B25, 84mm bore and 75 mm stroke. The M52B28 (used in e36 and e46 328i) has 84mm stroke, could this crank fit in my car? Would this be a good way to increse stroke? Anyone tried this?

Also, I'm taking this information from wikipedia, so if it is incorrect PLEASE correct me!

632 Regal
04-18-2008, 04:25 PM
use the shorter rods and crank as long as the wristpin hole is in the same location, if not maybe use the longer stroke pistons, as long as the head CC is in the same shape and CC...easier to just swap engines and call it a day I would think.

Happy Camping!

healtoeit
04-18-2008, 10:51 PM
I seem to remember this is called getting the engine 'bored and stroked' or something like that.
Yep! I'm thinking about just increasing the stroke, however, if i have my engine torn up I'm going to go ahead and bore it as well. Any suggestions?

Ross
04-19-2008, 07:08 AM
A lot of work for ~18 cubes

healtoeit
04-19-2008, 10:46 PM
A lot of work for ~18 cubes
Think I should go w/ a more powerful engine?

GoldenOne
04-19-2008, 10:55 PM
if you get the crank, con rods, and new wrist pins its a plug n play upgrade for a bit more power

http://www.zionsvilleautosport.com/store/shop.mv?Screen=PROD&Store_Code=6134&Product_Code=3.03.2SK&Category_Code=CKE

healtoeit
04-19-2008, 10:59 PM
if you get the crank, con rods, and new wrist pins its a plug n play upgrade for a bit more power

http://www.zionsvilleautosport.com/store/shop.mv?Screen=PROD&Store_Code=6134&Product_Code=3.03.2SK&Category_Code=CKE

Have you done this to your car? seems like a good deal... anyone else agree?

GoldenOne
04-19-2008, 11:37 PM
Have you done this to your car? seems like a good deal... anyone else agree?

gathering all the pieces and getting ready to start that process for it...

Ross
04-20-2008, 09:05 AM
Assuming the extra displacement will get you 20 hp at best.
Lot's of easier ways to get 20 horse. Power is made in the head, the bottom is only a pump, granted a bigger pump will make more power.

healtoeit
04-20-2008, 11:10 AM
Assuming the extra displacement will get you 20 hp at best.
Lot's of easier ways to get 20 horse. Power is made in the head, the bottom is only a pump, granted a bigger pump will make more power.
True but, Horsepower sells cars and performance parts. Torque wins races.