I have been looking at replacing my e30 with a E34 for a while now. I've looked at 535i and 525i cars. What's the opinions on these vehicles? I'd be using the car as a daily driver/commuter. The difference in gas mileage isn't that big a deal to me. What's it like for maintenance on these engines? This is my biggest concern. I know the M30 has a timing chain, where the M50 has a timing belt. Any known issues with one over the other? Thanks

Hey. Both are great cars. I think you will like the much more availability of torque in the M30. Both run forever and both are lots of fun to drive especially with the 5-speed manual.

Coincidentally im selling my 1990 535i 5-speed. Its got 119k miles. Car is perfect. Wheels, remus, crossdrilled brakes...etc PM me if you are interested. Im in Scottsdale AZ.

Good luck.

Nick

If gas mileage isnt a concern why not go for the engine that has a little more power?? After all the m30 engine is bulletproof, one of the best engines ever made

And the gas millage isn't that bad on an M30. On mine I get about 25 mpg doing 80-90 all the way. About 15 mpg if I'm doing all city driving and about 17-18 if I have a mix of about 60-70% highway and the rest city.

M30 all the way.

I'm pretty sure all the M50s have timing chains too. It's the M20, in the 525i from 89-91ish, that has the belt.

Personally I'd stay far away from an M20-powered E34, especially with an automatic, because that's just not much motor for a 3500 pound car IMO. An M50-powered car wouldn't be too bad...but everybody here knows that I'd take the M30 every time and twice on Sunday.

More torque, a little more HP, very durable, easier to work on, the M30 has it in spades. It's not as smooth and refined as the M50, but I think it's a great engine anyway. Heck, I'm going through a lot of work to replace an M50 with an M30, so I better be a big fan, huh? :)

I've driven both types before deciding to go with an m30. The m30 basic engine design was in production for nearly 25 years. That means two things:

1) Yes, it is an older simpler design - taking pure displacement over gadgets like DOHC and Vanos.

2) By the virtue of being so old, it has been refined to the point where all the kinks, bugs, and gremlins have been more or less eradicated from this motor.

The m30 is so durable and reliable that it is often referred to as "bulletproof." It also has significantly more punch than an m50 - punch that you can feel throughout the RPM range. Gobs and gobs of torque that you can play with to your heart's content. The gas mileage is worse than an m50 but it is definitely manageable and a fair price to pay for the increased power.

The primary challenge is finding an m30 car with a 5 spd - only 5% of e34 535i's came with a manual.

A 535i 5 speed IS a fun car, same with a 525 5 speed, but I'd stay away from a 525 auto, as they are fairly pokey. Being all of these cars are getting old, I'd just buy what I could get the best deal on, and drive it. None of the 5ers are that great on gas, so I wouldn't worry about that either, hell, I get 25 highway in my 540i, which I'd stay away from if you don't want an EXPENSIVE car to work on.

The primary challenge is finding an m30 car with a 5 spd - only 5% of e34 535i's came with a manual.

really? now im going to tell my dad that. hes been haggling me about buying a car so old w/ over 200k miles.

really? now im going to tell my dad that. hes been haggling me about buying a car so old w/ over 200k miles.

Honestly? I would as well. It's a BMW, but it's still old. It might go over 300K easily, or it might die tomorrow. Again, it's just a old car.

If it don't have to be dead reliable, and you have other cars to drive, it would make a fun driver or project you can drive and work on at the same time.

BTW, spend the money for AAA with any old car, it's well spent.

Thanks for the opinions. I really am leaning towards a 535i with a 5 speed. There's one for sale locally with what looks to be good service history. I'm not ruling out a 525i 5 speed either, just leaning toward the M30. We'll see. I'll have to sell the E30 first, then decide. It's tough though. I just picked it up 6 months ago and really enjoy driving it. Small, light, and capable. I came from VWs, which are great and I enjoyed, just different driving personalities.
I'm sure the size of the E34 will give a different driving feel again. A little larger, perhaps not as tossable? What's the consensus on this? I really have to decide if the move up in size is something I need.90% of the time it's just me driving.

Whatever you do... DO NOT test drive the E34 M5. Once you do, you will have some serious problems. I came from a long line of m50s and have had one m30 recently.(two 325is, one 525i, one 528i, and one 535im) I drove the M5 once and that was it. I had a blast in all of them, but one test drive is all it took.

Nick

Whatever you do... DO NOT test drive the E34 M5. Once you do, you will have some serious problems. I came from a long line of m50s and have had one m30 recently.(two 325is, one 525i, one 528i, and one 535im) I drove the M5 once and that was it. I had a blast in all of them, but one test drive is all it took.

Nick

No, I know bettter than to do this. I've drooled over these in the past, like when they first came out. I can be pretty impulsive, and can see myself buying one just because. Other things I need to save the money for right now though. Maybe in the near future.

but I'd stay away from a 525 auto, as they are fairly pokey.
you aren't kidding... pokey is nice, I'd say downright sluggish. Enough to cause road rage in trailing drivers and make them think you are some greenie Prius driver in the wong car.


Truthfully my wife's saturn sl2 as well as most compact economy cars (probably not a geo metro or a yugo though) will out accelerate you in an auto, unless you put it to the floor in sport or manual mode, then you can kind of no lag behind TOO MUCH until the engine comes on song and you can catch up.

m50 autos need some torque low in the power band. hmm and evo III 16g maybe? Wonder if the tranny could take it? Being a GM tranny there must be oobgobs of upgrades IF you can find someone who knows what the heck else it was used in.

you aren't kidding... pokey is nice, I'd say downright sluggish. Enough to cause road rage in trailing drivers and make them think you are some greenie Prius driver in the wong car.


Truthfully my wife's saturn sl2 as well as most compact economy cars (probably not a geo metro or a yugo though) will out accelerate you in an auto, unless you put it to the floor in sport or manual mode, then you can kind of no lag behind TOO MUCH until the engine comes on song and you can catch up.

m50 autos need some torque low in the power band. hmm and evo III 16g maybe? Wonder if the tranny could take it? Being a GM tranny there must be oobgobs of upgrades IF you can find someone who knows what the heck else it was used in.

It wasn't as bad as my old Mercedes 240D which did 0-60 in the same day. The 300D was a rocket in comparison. Even my old Volvo 240s would outrun a 240D Mercedes.

As far as the tranny, if you know what to look for, it's available, with the exception of the converter if it's got a weird pattern. As far as shift kits and stuff, they should be available.

Over the years some BMWs, Jags, Rolls, Volvos, ect... used various trannys, some of which are GM. I had a old Rolls I got for a song with a bad tranny, it used a GM TH400. I had it rebuilt for about $200.00, and made a little money on the car. The RR dealer (if I remember correctly) told the guy I got it from it would be like a 4K job, FOR A TH400! The Rolls wasn't worth much more then that at the time, and even today in it's condition would have a hard time fetching 8K.

That's also what sucks about the ZF in my 540i. The kit costs about 3 times what the old 4 speed auto does in my 735iL, plus it has a bunch of other stuff the old 4 speeds didn't have. Not to mention $$$ fluid it requires (unless I find something else that'll work).

But yeah, 525 autos ain't that quick, and the economy isn't that great, either. Did they even make a 525 auto for Europe, or was it NA only?

I think it needs to be added that the m30 was specifically designed for the original ///M1 Supercar - the mother of all ///M cars, so the engine has some great heritage behind it.