540i m62b44 stroked? - The Unofficial BMW M5 Messageboard (m5board.com)

#bmw# · 28th August 2008, 17:24

Hello.

Iam newbie in forum. Could someone help me out. It`s possible to stroke m62b44 engine by using bmw orginal parts. Exsample n62b48 or s62b50 bottom parts. Did someone tried before?

6spd · 28th August 2008, 21:48

I haven't seen anyone in the last four years talk about it.
You would need a S62 crank and flywheel, then custom pistons with the wrist pin relocated for the stroke.
Where you planning using the M62 or S62 rods? The rod journals are different sizes.

#bmw# · 30th August 2008, 14:38

Quote:

Originally Posted by 6spd

I haven't seen anyone in the last four years talk about it.
You would need a S62 crank and flywheel, then custom pistons with the wrist pin relocated for the stroke.
Where you planning using the M62 or S62 rods? The rod journals are different sizes.

Does s62 crank fit perfectly to m62 block without modifications? Sorry my english, but what is wrist pin. Iam planning to use S62 crank, S62 connecting rods and M62b44 pistons and taller cylinder head gasket.

Can someone help me, if M62 and S62 have a same size of piston pin?

blueaudis4 · 30th August 2008, 19:15

I have the stock S62 M5 cams from my car if you want them for your project.

6spd · 30th August 2008, 22:34

The wirst pins are the same .866 in diameter, its the location of the hole on the piston that different.
I hope to have more info by the end of the week.
Also I will look to see if the N62-4.8 parts can work in the M62 4.4
This would be the better option if it works

6spd · 31st August 2008, 07:03

The S62 and M62 cranks share the same main bearings but the rod bearing journals are different. S62B50 49mm, M62B44 48mm, also just for reference the N62B4.8 54mm
Alot of the N62B48 parts just don't seem to swap

#bmw# · 31st August 2008, 22:16

blueaudis4: thanks, but I can't use m5 cams cause i have m62 from -98 without vanos.

Why n62b48 parts won't fit if crank, con rods are in use. Thank you for info.

6spd · 2nd September 2008, 08:49

Quote:

Why n62b48 parts won't fit if crank, con rods are in use.

The rods are junk, the bolts come in from a angle.
The pistons are 1mm larger(93MM)
The main and rod bearings are much larger diameter.
The stroke of the crank is 88.3

You can bolt in everything from the S62 except the pistons, which you could get aftermarket cheaper then factory anyway.
You could also do slight machine work(machine rod journals to 1.890") to the crank and use longer rods and light weight pistons.

#bmw# · 4th September 2008, 20:19

thank you for advice.

How about vibration damper, pulley and sprocket from S62 did they work in M62 block? If not what modification needed?

6spd · 4th September 2008, 20:53

Here is RealOEM's parts list, it might answer questions quicker for you.
Yes the damper/pulley and chain drive are different, look in this 540-4.9 buildup.
Work in progress [540i 4.9 Kompressor buildstory]

540 parts list

RealOEM.COM * Part Category Selection

M5 parts list

RealOEM.COM * Part Category Selection

Once you read all that and understand the amount of work that is needed, you might change your mind like me and just add different rods/pistons and topend work(Cams/port work/valves).