Need Help Determining Compression Ratio

[E turd]

I figure one of you guys might just know this off the top of you head, or be able to point me in the right direction. I tried searching this and several other forums, but couldn't find what I needed. I know are compression ration calculators on the internet, but I don't have all the specs I need to fill in all of the necessary info.


Anyway, what I am trying to find out is does anyone know what the resulting compression ratio will be for an m52b28 motor running m50 pistons? I am buying a motor with this configuration and I need to know CR so I can figure out how thick a head gasket I need to get for the motor to run on 91 octane well.


So, if anyone knows or wants to tell me where I can find this info I'd greatly appreciate it. TIA!

[whiltebeitel]

http://forums.bimmerforums.com/forum/showthread.php?t=1289394

He states around 11.25:1, depending on HG thickness. Is this the one you are buying?

[E turd]

It is the one I am buying. I spoke to him on the phone and he doesn't know exactly what the CR is and the guy he told me to contact isn't returning my call. Plus, I don't think knowing what the CR is "around" will be very helpful in determining what head gasket I need to get. Seems to me like that's one of those pieces of information where the more accurate it is, the better.


I know I can change the pistons back to the original ones, but it's not the most cost effective and I'd hate to undo the work that has already gone into the motor as it is if I don't have to.