View Single Post
      04-23-2012, 09:11 PM   #31
shotman
Registered
0
Rep
4
Posts

Drives: bmw 335i
Join Date: Apr 2005
Location: Portugal

iTrader: (0)

Quote:
Originally Posted by Kalem View Post
I've checked the difference between 520i and 528i is in the compression ratio 11:1 vs 10:1
All parts are the same including engine blocks, crankshaft, cylinder head, head gaskets, drive shafts and transmission etc. The only part I find different is the piston, there are two types of pistons; one for lower compression engines (S858a=yes). Given the head gaskets are the same, the piston should be the part that reduced the compression ratio in 528i. Don't know if the quality of the two pistons are the same or not? Maybe just changing the head gasket to reduce compression ratio to 11:1 and remap ECU will do, any other thoughts?


The piston is the same for both engines on Z4.

http://www.realoem.com/bmw/showparts...70&hg=11&fg=20

http://www.realoem.com/bmw/showparts...70&hg=11&fg=20
Appreciate 0