Engine swap/rebuild
 

Hey guys, this is my first post. So I have an 06 525xi 6 mt and it has almost 200k on it. The body has no rust and it drives very well, so I really want to make it last since it's a great daily driver and gets pretty decent gas mileage. I do all of my own work and I have been thinking about buying another n52 with lower mileage and rebuilding it so I have a backup in case mine goes.
I have a few questions.
1. What's my best route to getting a lower mileage n52 to rebuild? Salvage auction? Does it have to come from an xi or can I get one from a rwd? (I know, multiple questions haha)
2. Will the n52k from a newer 528 fit in mine? If so I would rather get that since it's slightly more powerful.
Any tips or help is greatly appreciated!

If you are going to rebuild then the mileage is probably not a big issue really.

Are you trying to avoid boring cylinders (alusil block?) or other machining operations?

Its an aluminum magnesium block with no liners so I don't want to machine the block, I essentially want a low mileage block that I can build up from.

Is this your first bimmer? Remember, they are expensive to fix, even if you do your own work. May I suggest that you bank the money you will spend on the "spare" engine for a 12-year-old car and use it toward future repairs and/or mods. You have the base N52 engine there, which has proved to be one of the best that BMW made and should last to 300,000 miles with proper care and maintenance.

Look up the book value of your car. It's not worth as much as you think.

Its not that I think it's worth a lot, it's the fact that I live in Indiana and I have a 12 year old bimmer with no frame or body rust. Aside from the high mileage engine it is in perfect condition inside and out. You can't/shouldn't mod an n52 because of the alum/mag block with no liners. It was built for light weight, I intend on getting an n54 BMW at some point. I'm very aware of the cost of BMW repairs/maintenance. This is my daily and I want to have a fresh engine when this one decides to go, rather than trying to repair a major malfunction and spending that money on a high mileage engine.

By mods, I meant something that gives you pleasure (body kit, rims, tint, etc.) A 528 doesn't have enough to it for performance gains.

I'm just suggesting that the money and effort is probably not worth it. My opinion. Besides, something else could happen to that body in the interim (like a fender bender or worse).

Thats true, but that's the case with any nice car. There's always a possibility of something bad happening, with my car I'm assuming the engine will go first. If I have a fresh n52 I would feel a lot better about getting rims, etc. The engine currently has no issues and I take very good care of it, but I def want to rebuild an n52 to keep this as my daily for a good while. It gets awesome gas mileage, plus I just love the car in general. But I definitely see where your coming from.

Good luck in your quest!

Thanks man!