Can you safely boost the M3 motor with it's high compression???

bubba'sbimmer · #1 (**permalink**) 04-05-2009, 02:49 PM

Hey guys I am in desperate need of some more power and I'm feeling a turbo coming. My question is how much boost can you safely run on a motor that has 11.3:1 compression??? If someone could shed some light on this subject I would greatly appreciate it!

badboostedbmwm3 · #2 (**permalink**) 04-05-2009, 03:26 PM

Well, on completely stock motors (10.5:1 ratio) even stock headbolts... i've seen people run 13psi or more with meth injection
With a good tune I think you could see 8 or 9psi or maybe more with meth injection. Of course, you can always put in a .140 MLS headgasket and boost even more!
BTW, you should check out bimmerforums.com because there are more people and info!

bubba'sbimmer · #3 (**permalink**) 04-06-2009, 02:46 PM

thanks I appreciate the help. Not to second guess you but are you sure the ///M motor has 10.5:1? I read that they increased it to 11.3:1 for the 3.2.

bubba'sbimmer · #4 (**permalink**) 04-06-2009, 02:49 PM

Hey man and I see that your in Louisville?!! I would love to talk to you more or maybe find out where some of the euro guys hang out

blacklove7777 · #5 (**permalink**) 08-30-2009, 07:58 AM

I wouldn't suggest you do that! you need to at least lower compression first, that's the least. I suggest you research a little more on the effects turbo has on diffrent engine components first bro just to be on the safe side, you can bolt on all the parts but will it run without a catastrophic failure is the question? Unless you got money to go ahead and buy another s50 like that and if you do buy me one LOL

badboostedbmwm3 · #6 (**permalink**) 09-27-2009, 06:30 PM

Quote:

Originally Posted by bubba'sbimmer

thanks I appreciate the help. Not to second guess you but are you sure the ///M motor has 10.5:1? I read that they increased it to 11.3:1 for the 3.2.

Long time since reply....

But, EURO 3.2 motor received the 11.3:1 compression ratio not us!

blackedoutaudi · #7 (**permalink**) 10-23-2009, 01:00 PM

you can run boost on any compression.usually the higher compression,the lower the boost.but it is really all dependent on the tune.the tuner will know on the dyno what is lean and what boost level will not detonate .so dont listen to people when they tell you no.hope i helped.need anything,feel free to pm me.have a good one

badboostedbmwm3 · #8 (**permalink**) 11-02-2009, 05:08 PM

Quote:

Originally Posted by bubba'sbimmer

Hey man and I see that your in Louisville?!! I would love to talk to you more or maybe find out where some of the euro guys hang out

Feel free to pm me!