question about boosting m42

x2dg · #1 (**permalink**) 03-04-2006, 02:17 PM

i know this is a stupid question but not every engine can take the same stress internally but i would like to know if a stock internals on a m42 could handle 7psi, and would the internals wear out fast??Thanks!!!!!!

ILiveToRide · #2 (**permalink**) 03-04-2006, 03:07 PM

Stock internals can handle much more then that. But the high compression ratio becomes a problem rather quickly.

More then 7psi have been run on stock engines though.

x2dg · #3 (**permalink**) 03-04-2006, 05:28 PM

yea i know many cars that push more than that on stock internals, i jut thought a m42 could be a bit weaker, so i should get ticker headgaskets or double it, what compression does a m42 got??

ILiveToRide · #4 (**permalink**) 03-05-2006, 12:21 AM

I ment specifiacally the M42 can take alot. It's a very good design, oil cooled pisons etc.

For 7psi I don't think you need to do anything.
12psi (or there abouts) have been run on stock motor. M42 in a E30.

CR is 10.0:1

x2dg · #5 (**permalink**) 03-05-2006, 08:53 AM

ok sounds good to me, ive just been thinking cause i dont have the kind of money to deal with 6L cuase turbo setup become more expensive so i could build my own turbo wich makes it easier and cheap.Thanks!!!

do you own a m42??

ILiveToRide · #6 (**permalink**) 03-05-2006, 09:51 AM

Quote:

Originally Posted by x2dg

ok sounds good to me, ive just been thinking cause i dont have the kind of money to deal with 6L cuase turbo setup become more expensive so i could build my own turbo wich makes it easier and cheap.Thanks!!!

do you own a m42??

No not at the moment, I've had two 318is '90s though.
Had one for 3 years and one for one year, had both at the same time. Sold the last one a year ago.

x2dg · #7 (**permalink**) 03-05-2006, 09:57 AM

oh cuz im confused wanting know what problems do they give you? anything major?

ILiveToRide · #8 (**permalink**) 03-09-2006, 07:27 AM

Quote:

Originally Posted by x2dg

oh cuz im confused wanting know what problems do they give you? anything major?

M42? Nothing major. Didn't have any problems with them.

x2dg · #9 (**permalink**) 03-09-2006, 06:28 PM

like how many miles did you have on it??

VenomRS4 · #10 (**permalink**) 04-14-2006, 11:56 AM

I have a 95 318is with the M42 and its been great. It's approaching 180k miles without ANY mechanical problems at all. And I have owned the car for a while now. Very reliable engine.

x2dg · #11 (**permalink**) 04-14-2006, 02:30 PM

do they also come with bad cooling system like water pump, etc...

nefarious79 · #12 (**permalink**) 04-16-2006, 06:13 AM

putting in a thicker headgasket is a bad idea, it lowers compression but it is also more likely to be "pushed out" because of increase surface area in the combustion area. with proper tuning even engines with high compression can run a pretty good amount of boost, a good tuner on a stock RSX approx 11.0:1 compression can run 8-10psi safely

frank1975 · #13 (**permalink**) 05-12-2006, 11:16 PM

I run 10 psi fine

Tvan · #14 (**permalink**) 05-17-2006, 07:53 AM

Umm if it's an e30 with an M42, you won't have any knock sensors. That would probably not be a good thing if you were to push that much power through it...

nefarious79 · #15 (**permalink**) 05-17-2006, 03:08 PM

Quote:

Originally Posted by Tvan

Umm if it's an e30 with an M42, you won't have any knock sensors. That would probably not be a good thing if you were to push that much power through it...

There are a lot of M20's and M10's that are turboed, I could be rattling off engines all day long that dont have knock sensors that people boost, just use good quality high octane gas and have your car tuned, if nothing else just get a dyno commander or AEM UEGO wideband A/F gauge