my stroker recipe: good/bad?

[guibo09]

I think 140mm rods come from NON-vanos m50s, but I'm not 100% sure

here is one source that says otherwise, although reliability is questionable:

http://www.bmwe21.net/forum/viewtopic.php?p=48743&sid=95528f7686b0eeee65beec5e26322e64

and another more reliable source:

http://www.turrisimotorsports.com/race_team/bmw_specifications/engines/M50B25/M50B25.htm

also just calculated wrist pin position relative to the block (in mm):

OEM: 97.5 bdc to 172.5 tdc
Stroker: 97.1 bdc to 182.9 tdc

so with the 140mm rod, there is no risk of the piston skirt exiting the block at the bottom of the stroke. now it remains to see if is possible to trim enough of the top of the piston to clear the head. im guessing bumping up the compression will help with this.

[SpecM]

I think 140mm rods come from NON-vanos m50s, but I'm not 100% sure

[guibo09]

so here is my plan for a 3.0L (2989cc) stroker. i would like to know if anyone has done it, or if they foresee a problem.

- m20b25 bored to 86mm with 885 head with some porting/polishing + valve job, MM beehive springs, new OEM rockers
- 85.8mm forged crank from S50B30 US (any other source for these?)
- 140mm rods from M50B25 vanos (any other source for these?)
- custom 11:1 or higher forged pistons with stock piston shape (most likely JE) 86mm
- 288 shrick cam (i will calculate the proper dynamic compression ratio based on cam for 91 octane)
- MSII
- exhaust/intake tbd.

the goal is to keep reasonable stroke/bore and stroke/rod ratios that are tested and true.

thanks for any input!