View Full Version : engine rebuild vs. engine swap

06-06-2008, 10:47 AM
I just recently picked up an '81 e21 320i and my Dad's telling me it may need an engine rebuild. I'm not to auto mechanically inclined, so my question is:

Engine rebuild or engine swap?

Any feed back would be much appreciated. I've read that it my me better to rebuild and throw a turbo on for more bang for the buck. Is this true? Also, if anyone can suggest what engine swaps and approximate costs? Any shop suggestions? I live in the GTA, and cost is a factor. I know this may not be cheap but all the help would be greatly insightful.


06-06-2008, 11:27 AM
E30 M20B25's are like free, pull up a truck to Bimmersport and see how many you can fit in the back. lol.

But seriously I'd probably do that. Call them and ask for a quote.

06-06-2008, 11:59 AM
+1 for a m20b25 swap.

06-06-2008, 12:17 PM
+2 for a m20b25 swap.

06-06-2008, 12:19 PM

06-06-2008, 12:54 PM
thanks for the response guys!

I've heard ppl say that an m42 and m50 can fit? Does anyone here know if it is possible? Btw does anyone know how much I would be lookin @ for the m20 swap?

thanks again!

06-06-2008, 01:05 PM
they all can fit, m20s are pentiful and cheap around here.

You can usually pick up m20s for $300-600 used.
ECU and harness - ~$300

not sure what else you'd need in terms of tranny / driveshalfs, etc, then jus labour is left.

06-06-2008, 01:07 PM
i think s50-s52 fit too. I've seen someone's e30 with s50..but might be more expensive

06-06-2008, 01:32 PM
Anything will fit with enough money. You asked for a budget swap, and we provided you with one that will make 168-190hp easily and be dead reliable. Bimmersport has also done an E21M20 swap, they know the tricks (like the custom driveshaft necessary).

06-06-2008, 02:11 PM
yup, it all depends on the engine you want to put in. different engines are more readily available and thus cheaper. also, different engines will require varying amounts of customization. best thing to do is call a shop and get a quote. and trust me, you want to call bimmersport. they have done it many times and are very qualified. they have an excellent reputation around here. there's a link in the links bar along the top of the page called "sponsors." click there and you will find the link to bimmersport.

06-07-2008, 12:33 AM
thanks guys I appreciate all the feed back. very insightful! do you know if bimmersport can provide an engine? or do you think its better to out source one myself?

06-07-2008, 01:08 AM
I'm also very interested in this same topic.

I just bought a 91 318Is, How much does the average rebuild cost?, I will be doing the Re and Re myself.

Does Bimmersport do stock rebuilds? If not what is a good shop that is familiar with bmw's to do the rebuild?


P.s Sorry for thread jacking.

06-07-2008, 10:12 AM
thanks guys I appreciate all the feed back. very insightful! do you know if bimmersport can provide an engine? or do you think its better to out source one myself?

Last time I checked they had a stack of M20s. There are so many E30 guys doing swaps that good M20s are just laying around. It'll be cheaper doing it all through them (plus that way you know the motor is good, or else they will fix it).

And to the thread jacker, I have no idea of the cost but Bimmersport definitely does rebuilds and knows the cars.