View Full Version : 2.9 stroker

02-18-2009, 01:38 AM
So apparently you can build a sick stroker motor out of an M50 using a 3.0L S50 crank and connecting rods. I've read on other forums that guys are getting in the area of 240-260 *RWHP!!* with this setup using M3 cams, 540i HFM, 24lb injectors, cold air, and software. However, I can't find a DEFINITIVE answer on exactly which pistons are used - some say M50, others say M52. Compression is supposedly around 11.5:1.

Just wondering if anyone has heard about this and has solid info on it. I've seen M3 cams for like $100 in the past on ebay and cranks for around $400 here and there from time to time. I'm just intrigued by the possibility of building a cost-effective beast out of the Vanos M50 sitting in my garage, waiting to serve a purpose.

02-18-2009, 02:00 AM
Software will be $$. I wouldn't really call it a cost-effective build but I think a s52 with bolt-on mods will be better since its already a factory built stroker, even though the idea of a 2.9L sounds more "exotic"

02-18-2009, 12:43 PM
I like to be different sometimes - even when it comes at a price - but I'm thinking that if I have a complete car with an M50 with a fresh head (previous owner bent a bunch of valves on a missed downshift), I could probably get this done and running for only a couple grand. Apparently, Active has software for every possible combination of mods with the 2.9 for around $400, which I could live with. I think they were sort of the 'pioneers' of the whole thing. However, they seem to be pretty hush hush about the specifics.