Change BMW 3 E46 engine from 3.0L to 1997 5 series 2.5L engine?

Recently my BMW head gasket got burnt and it affected other parts of the engine like the piston and the cam shaft. At 160K+ miles, I thought it%26#039;d be a good idea to change the change. I was offered a 5 series engine by my mech. I%26#039;m wondering one or two things that may not make it work out. Can any offer advise please. I think the ECU for the 5 series will be different from mine and I also think the engine mount and things like pumps etc will not be the same.


Thanks for taking time to read.|||sorry to say while transplants like that can be done...the cost estamate and ease of work is ALWAYS underestamated...always....costs run 2 x,,,3x what you think and a month later you may be working out the bugs...|||Yeah, this definitely isn%26#039;t a good idea unless your mechanic is extremely skilled and wants to install it for free.|||Couple of basic issues. If you are in a U.S. state with an emissions test regime, you may not be able to pass the inspection with an older engine (E46 was 1999 and later). Also, you probably have a double VANOS M54 engine (dual variable valve timing), and the older engine is probably a single VANOS (intake timing only) version. Mileage will suffer. I can%26#039;t recall, but suspect the engine you%26#039;re being offered is an M52.





In the U.S., the engine I find listed for a 1997 car is the M52B25 (2.5 liter) in the 523i car, and the M52B28 (2.8 liter) in the 525i car.





I%26#039;d hesitate over an engine change to an older engine. Ideally, you might find an engine from your year, at a specialty dismantler. I know there is such a dismantler in Rancho Cordova, California, and that they ship. Other regions probably have similar options.





Good luck.