Rebuild M50 325i (1994 325i)

///M325i · 12-07-2010, 12:04 PM

Hi, i have a 1994 BMW 325i and i would like to rebuild the engine on it. After the rebuild is done i would like to turbo the engine. I wanted to know if this is even worth it, my engine has 250xxxkm and that's a lot. All i'm looking for is MORE power and better performance!! So my question is: Is it worth rebuilding an old 1994 m50 with 250xxxkm on it then shortly after turbochargeing it? And would the give me the power and better performance i'm looking for??

hockeyfan27 · 12-07-2010, 12:27 PM

When researching whether or not I was going to buy my car -it was high KM and I was a bit apprehensive - I read that some race team somewhere would look for BMW blocks to rebuild into race engines in the scarp yard. They felt it was better stress tested then a new block would be and was a better starting point.

craz azn · 12-07-2010, 06:47 PM

Not worth it at all.

Dissembler · 12-07-2010, 07:23 PM

Find an M52 and build that for boost. Collect all the parts you'll need (exhaust pieces, intercooler, lines etc etc) and then that way you will still have a DD, and when everything is ready, drop the new motor in over a weekend.

Or V8 swap

dble Trouble · 12-07-2010, 11:00 PM

Quote:

Originally Posted by hockeyfan27

When researching whether or not I was going to buy my car -it was high KM and I was a bit apprehensive - I read that some race team somewhere would look for BMW blocks to rebuild into race engines in the scarp yard. They felt it was better stress tested then a new block would be and was a better starting point.

That was BMW in the early '80's and they didn't go to the scrap yard, they were specifically looking for cars that had dd'd for 40,000km and use that block, anything more than that they felt might have been TOO stressed, that was in the heavy turbo charging days when they were making 1200 hp!

///M325i · 12-08-2010, 10:01 AM

Quote:

Originally Posted by Dissembler

Find an M52 and build that for boost. Collect all the parts you'll need (exhaust pieces, intercooler, lines etc etc) and then that way you will still have a DD, and when everything is ready, drop the new motor in over a weekend.

Or V8 swap

yeah ehh, you think a 328 motor will be better off turbocharged then a 325i? Well i fully agree with you but the thing is i dont want to swap out the motor, that's too much work plus if i was going to swap out the motor i would swap it for the s52 3.2L that was the original plan but things kept coming up. So i just settled for the quick engine rebuild and the forced induction to get that sweet power

But thats not a bad concept you've given me get all the part together then throw em in over the weekend. Also have another question whats "DD"?

///M325i · 12-08-2010, 10:06 AM

Quote:

Originally Posted by craz azn

Not worth it at all.

Really? Why do you say that? And do you have an alternative to getting more power out of an old 94 325i if the engine rebuild and forced induction wouldn't be worth it?? All i'm looking is more power/performance.

///M325i · 12-08-2010, 10:21 AM

ok just found out what DD mean sorry lol it mean daily driver lol

craz azn · 12-08-2010, 11:06 AM

Quote:

Originally Posted by ///M325i

Really? Why do you say that? And do you have an alternative to getting more power out of an old 94 325i if the engine rebuild and forced induction wouldn't be worth it?? All i'm looking is more power/performance.

Add up the cost just in parts to rebuild a motor. I think you will find your answer.

///M325i · 12-08-2010, 11:29 AM

Quote:

Originally Posted by craz azn

Add up the cost just in parts to rebuild a motor. I think you will find your answer.

Well i don't want to say money isn't an issue because anyone who says that would be telling a lie. I don't want to blow all my money on an engine rebuild and a nice turbo system either, but i hear you i'm not all that experienced with BMW and you clearly seem to be so thanks for the advice. I'm already looking into the cost of the rebuild i haven't decided where i'm going to do it yet. But i'll keep in mind the not worth it part.

craz azn · 12-08-2010, 02:42 PM

Quote:

Originally Posted by ///M325i

Well i don't want to say money isn't an issue because anyone who says that would be telling a lie. I don't want to blow all my money on an engine rebuild and a nice turbo system either, but i hear you i'm not all that experienced with BMW and you clearly seem to be so thanks for the advice. I'm already looking into the cost of the rebuild i haven't decided where i'm going to do it yet. But i'll keep in mind the not worth it part.

Just for a set of new forged pistons is about the same price as a nice used M52 engine just like Dissembler suggested. It's relatively cheap, tons available, and stronger than an M50 if you seriously want to boost it. And even if you don't, it is a decent platform to start with for bolting on some go fast parts to keep you entertained for the time being.

JvzwetE36325 · 12-08-2010, 03:19 PM

I'm selling my m52 btw

JvzwetE36325 · 12-08-2010, 03:22 PM

I have an M50, and yes its a strong motor but rudy is right, the m52 is a better platform for boost, forged connecting rods and crank, 84mm bore x84mm stroke. Slightly bigger displacement as a 2.8, can be further bored to a 3.0L, thick iron block (strong for boosting)

///M325i · 12-09-2010, 12:56 PM

Quote:

Originally Posted by craz azn

Just for a set of new forged pistons is about the same price as a nice used M52 engine just like Dissembler suggested. It's relatively cheap, tons available, and stronger than an M50 if you seriously want to boost it. And even if you don't, it is a decent platform to start with for bolting on some go fast parts to keep you entertained for the time being.

hmmm well now that i think about it, it's not all that bad if i were to swap out my 2.5L for a 2.8L but obviously keeping the m50 intake manifold.

///M325i · 12-09-2010, 01:04 PM

So the bottom line is, it would be way better to get an m52 and build that rather then rebuilding an old m50 then turbo charging it. hmmmmm