e30 engine lifespans/reliability

[new2bmw]

Just want to try to figure this out. I was wondering if anyone has been here long enough to know the average kilometers/miles that all of the e30 engines last. I know maintenance, driving habits, location all play a factor in the life of an engine, i am not looking to be that thorough, although if someone wants to crunch numbers and figures, feel free.
I am interested for my own reasons, i am trying to decide whether to go m10 turbo or m20 in my car, but I think it might be interesting to see the numbers. I guess the only way to do it is to enter your year of car, engine (for those who don't know or if you have swapped), where you are and the mileage/kilometers on your car. If this has been done or just gets flamed to shit, just let me know whether the m10 or m20 is more reliable, and can withstand the most abuse.
cheers guys

1984 318i
M10
220,000KM

1989 325i
M20
300,000KM

Ontario Canada

[Jean]

I don't think anyone will be able to tell you any meaningful data on this, it's a wash. Why don't you do a compression test / leak down on both and pick the one of the two that way?

P.S. I still have the 2.0L m10 crank you wanted last year, should I throw it away or do you still want it?

[McGyver]

so m10 with boost that it wasn't designed for, or m20 oem? why dont you do the leakdown and then rebuild? or buy the cheap one and then swap in a new engine. it sort of sound like you are swaping a new engine into your car, and if that the case just do an m50 swap.

[jason325e]

some m20's last for 300k+ miles , and some blow up before they hit 100 , its all about the previous owners and how you plan to treat that car when u own it.

[Mauiwowi]

my m20 just went to 311k and blew out 2 weeks ago. Doing it big over here!

[VinniE30]

What do you guys mean "blow up"? What goes first? Anything can go forever with replacing parts.

[bimmer_E30]

^^^i wanna know about this too.

[xwill112x]

most of the time, the demise of an m20 is a broken timing belt.

[Mauiwowi]

What do you guys mean "blow up"? What goes first? Anything can go forever with replacing parts.

mine threw a rod which left a hole the size of a softball in the block- aka it blew up.

edit- that was because no oil, and there was no oil because im fucking hardcore.

[Adrian_Visser]

M10's are pretty bulletproof, then again so are m20's if yo replace the timing belt on time and adjust the valves.

It all comes down to how each engine was looked after during its life and what kind of abuse it has seen really.

[VinniE30]

most of the time, the demise of an m20 is a broken timing belt.

Which is the result of improper maintenance. What I think OP wants to know is when/how they die when properly maintained and what causes the engine to die.

[xwill112x]

Which is the result of improper maintenance. What I think OP wants to know is when/how they die when properly maintained and what causes the engine to die.

250k-300k from an enthusiast owned, wound out, enjoyed e30 325iS. If its an "e" then who knows, 500k?

[Lance Racing]

Even with good maintenance eventually they burn a lot of oil (say over 300k miles) so people throw in the towel and rebuild so they aren't adding a quart of oil every time they get gas.

[wildstoats]

Well, I met a guy a 5er Fest one year that had over 500,000 miles on his 528e, original engine. So it is really a matter of maintenance and how far you are willing to go to maintain the vehicle.

[E30Kaiser]

Mobil ran a 325i a million simulated miles on a dyno basically. Not really an accurate test that crosses over to real life driving but all the same. Apparently the car is pretty nice to drive still.


Several 325e's on here have over 500k miles.