e30_capri 0 Report post Posted January 23, 2010 (edited) Hey there Ive been searching all over the net for information on building m20b27 engines and have all bar a few facts i need. I have the following: 885 head complete M20b27 block complete(well until last night that is), it has the the casting no. [27 6E A]. Now I believe that there were two slightly different types of m20b27, and I am led to believe I have the higher compression one. The pistons have an approximately 1mm raised centre and I think the other ones have a dished piston? I am stuggling to find the info I need. I had a magazine i got off mark247 but im blowed if i can find it. It had all the info about the above and i think i saw someones scan of it on here but cant find it. It was a uk BMW mag perhaps? Can any one tell me what compression ratio this block/engine is? It came out of a german assembled 1986 525e and had the 200 head and motronic ignition, also was an auto. Any help would be much appreciated. Cheers, Pete. Edited January 23, 2010 by e30_capri Quote Share this post Link to post Share on other sites
Forrest 35 Report post Posted January 23, 2010 (edited) Thread I made 6 months ago. Still umming and ahhing about a 2.7/2.8 http://www.bimmersport.co.nz/forums/index....;hl=m20+stroker Heaps of good links/advice in there. Edited January 23, 2010 by Forrest Quote Share this post Link to post Share on other sites
e30ftw 410 Report post Posted January 23, 2010 Dished pistons are 10.2:1, the raised pistons are 11:1. Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted January 23, 2010 Quote Share this post Link to post Share on other sites
e30ftw 410 Report post Posted January 23, 2010 Here is another usefull bit of info, http://www.bmwccn.no/rogaland/Mahle_m20.html Quote Share this post Link to post Share on other sites
e30_capri 0 Report post Posted January 23, 2010 Woohoo!!!!! cheers peoples my head is finally out of the sand, i have the 11.1:1 bottom end therefore should end up with around 10.4:1 CR and my bottom end seems to be fairly well within factory wear tolerences so am pretty happy now . Ok so any recommendations on places to purchase rings bearings gaskets etc, any bad experiances with certain brands. Can PM me if you dont want to go dishing dirt for everyone to see! Cheers heaps, Pete. Quote Share this post Link to post Share on other sites
e30ftw 410 Report post Posted January 23, 2010 Gavin from Euro-italian parts (Forum sponsor) can do it all. Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted January 23, 2010 Woohoo!!!!! cheers peoples my head is finally out of the sand, i have the 11.1:1 bottom end therefore should end up with around 10.4:1 CR and my bottom end seems to be fairly well within factory wear tolerences so am pretty happy now . Ok so any recommendations on places to purchase rings bearings gaskets etc, any bad experiances with certain brands. Can PM me if you dont want to go dishing dirt for everyone to see! Cheers heaps, Pete. euromarketing (barry ) in mangere for rings ,bearings etc Quote Share this post Link to post Share on other sites
e30_capri 0 Report post Posted January 23, 2010 Sweet cheers thanks for all your help folks, will do a project thread one day, need a decent camera first though. Quote Share this post Link to post Share on other sites
mark247 39 Report post Posted January 23, 2010 (edited) I had a magazine i got off mark247 but im blowed if i can find it. It had all the info about the above and i think i saw someones scan of it on here but cant find it. It was a uk BMW mag perhaps? You lost my magazine! Edited January 23, 2010 by Mark247 Quote Share this post Link to post Share on other sites
e30_capri 0 Report post Posted January 23, 2010 yea i think it mighta grown legs!!!!!! grrr Quote Share this post Link to post Share on other sites
djs325 0 Report post Posted January 24, 2010 Was going to quote that site as well, excellent comparison between the different M20 2.5/2.7 pistons. Here is another usefull bit of info, http://www.bmwccn.no/rogaland/Mahle_m20.html Quote Share this post Link to post Share on other sites
