Maintenance is great. I've only had to do minor things to it. Since I'm 6'5 I did have to re-weld all my stalks to be 30 degrees back and do a bunch of work on the steering column and wheel to bring it forward 8 inches and up 2, some stuff on the throttle body from coolant leaks, but other than that it's been great. I've put 100k+ km on it in just the past two winters since I live up in the boonies. I'm alerted of oil changes by the lights in the centre of the dash as well. I haven't done much of any work at all except what I mentioned since buying it and it's been smooth sailing for multiple winters now. The M20B25 is built like a tank. I have it sitting on B8's on H&R sports springs so the handling couldn't be better, and I did some minor ECU tuning on it to give me a little more power on the low end. The idle has remained at a perfect 750 as well, and I can get it down to 6.8L/100KM if I baby it. It's the perfect car [0]. I've even binned it a few times and it's still going strong.
I've also got a period correct radio in there from bmwradios.com (radio wizard from estonia) who gave it bluetooth functionality along with a period correct panel in the console for a microphone, so I can talk hands free while I'm driving. He also modified the radio for me to read out the different GTA 3/4/5 radio stations and I can switch them around as I only listen to GTA radio and commercials when driving [1]. Besides it being 900kg with no airbags, it's the perfect car.
Between e30zone, the bentley manual, and realOEM [3] amongst the other infinite amount of resources it's impossible not to do your own work on it and it's usually easy. It really is a thinkpad in car form. Most parts are still produced and if they aren't you can get any number of things from third party shops like e30garage.no [4] if it's not on FCPEuro. Lot's of parts are also plug'n'play between different BMW models like steering racks which are quite easily swappable.
Maintenance is great. I've only had to do minor things to it. Since I'm 6'5 I did have to re-weld all my stalks to be 30 degrees back and do a bunch of work on the steering column and wheel to bring it forward 8 inches and up 2, some stuff on the throttle body from coolant leaks, but other than that it's been great. I've put 100k+ km on it in just the past two winters since I live up in the boonies. I'm alerted of oil changes by the lights in the centre of the dash as well. I haven't done much of any work at all except what I mentioned since buying it and it's been smooth sailing for multiple winters now. The M20B25 is built like a tank. I have it sitting on B8's on H&R sports springs so the handling couldn't be better, and I did some minor ECU tuning on it to give me a little more power on the low end. The idle has remained at a perfect 750 as well, and I can get it down to 6.8L/100KM if I baby it. It's the perfect car [0]. I've even binned it a few times and it's still going strong.
I've also got a period correct radio in there from bmwradios.com (radio wizard from estonia) who gave it bluetooth functionality along with a period correct panel in the console for a microphone, so I can talk hands free while I'm driving. He also modified the radio for me to read out the different GTA 3/4/5 radio stations and I can switch them around as I only listen to GTA radio and commercials when driving [1]. Besides it being 900kg with no airbags, it's the perfect car.
Between e30zone, the bentley manual, and realOEM [3] amongst the other infinite amount of resources it's impossible not to do your own work on it and it's usually easy. It really is a thinkpad in car form. Most parts are still produced and if they aren't you can get any number of things from third party shops like e30garage.no [4] if it's not on FCPEuro. Lot's of parts are also plug'n'play between different BMW models like steering racks which are quite easily swappable.
[0] https://i.imgur.com/kjt2ATf.jpeg
[1] https://i.imgur.com/uenzzLq.mp4
[2] bonus winter video: https://i.imgur.com/KG2IlgN.mp4
[3] https://www.realoem.com/
[4] http://e30garage.no/