My E85 pre-facelift was equipped with the standard manual heated seats. When driving longer distances my lower back always started to hurt. Besides, when driving more sporty in the corners you clearly notice the lack of lateral support (especially for the passenger).
The Z4M seats are very hard to find in The Netherlands and in Germany and usually go for incredibly high prices. Hence, I looked for alternatives and decided to go for the E46 M3 seats as they offer much more support, specifically the ones with the inflatable bolsters for the lower back + side. On this forum I found some great info regarding the fitting of these seats in an E85, for example the two topics below:
e46 M3 seats in a Z4, will they fit?
E46 M3 seats fitted
After a while, I found a pair of electric E46 M3 Coupé front seats in Germany, near Aachen, which is a couple hours drive from my home. As I wanted to fully test the seats (electric adjustments, seat heating and the inflatable bolsters) I had to bring the Z4. I didn't want to bother anyone by coming along with an extra car to transport the seats since it was a long drive, so I just removed the passenger seat to make space. I installed the M3 seats and tested them on the spot; luckily everything worked fined. For the drive home, I just put the "old" drivers seat on the "new" passenger seat
The E46 M3 seats are so much better than the standard seats! They offer a lot more support and adjustment possibilities, so I am really happy with the upgrade. The looks are also fine for me, even though they look a bit more bulky. I currently have my hardtop installed so I cannot make clear overview pictures, but in the two topics above you will find some good photos.
Some differences I noticed:
- I have the feeling the seat heating is not as warm as the standard Z4 seats, but I didn't measure it so it is hard to tell. Perhaps related to coupe vs. convertible?
- The seat sitting height is higher now, but this is due to electric seats vs. the manual seats I had.
- The seats go a little less far back as they are somewhat wider in the back. Removing the backrest tilt levers already helps, but I find them quite useful as it eases access to the small storage compartments behind the seats. One of the three levers is smaller, so I am currently using this one at the moment for the driver seat, but I will look into 3D printing a small version for both seats.
The seats are plug-and-play as described in the above topics. I should note, however, that I have an early (2003) E85 model which has the wiring for electric seats already installed, despite the fact is was equipped with manual seats. Hence, all electric functionality works without any issues. There are, however, three things to consider:
- I installed the E85 seat belt tensioners on the M3 seats: I have read somewhere that the M3 tensioners might give an error in the E85. My M3 seats came without any belt tensioners, so I had to use the E85 ones anyways. Also, since I was driving without passenger seat, I had to clear the safety error afterwards.
- The E46 M3 seats don't have a seat belt guide near the headrest. Sometimes, this makes it slightly more difficult to grab the belt when buckling up. Also, while driving the belt is near my neck, which is not very comfortable. There seem to be belt guides for E46 models that are mounted to the headrest; not sure if these fit well, but otherwise I will design and print this myself.
- The standard E85 seats have a bracket for the seatbelt on the seat rails. The E46 M3 seats are from a Coupé model, which can tilt forwards to allow passengers to step in the back. Hence, there is no bracket on the seat rails as the seat belt is mounted on the floor/pillar(?). As a temporary solution, I just attached the seatbelt to the rear bolt of the rails (see photo below). However, when moving the seat fully backwards, the seat will slide over the seatbelt, which might cause some damage/wear over time. Also, I didn't really like the construction as the bracket will be loaded under bending during an impact. Already bending it upwards is possible, but this will restrict the backward movement of the seat even more.
Instead, I went out looking for standard E46 seats that have these brackets. I found a pair from some manual seats that were damaged, so I could get the rails for a cheap price. I had to drill out the brackets from the rails on the door-facing side, but could use the bolt and square-nut from the seatbelt tensioner bracket later on for mounting. Below are some photos to further explain this.
If you have any questions or if anything is unclear, let me know
Mounting the seatbelt to the rear bolt of the rails. I only used this as a temporary solution.
From the donor seats: the bracket for mounting the seatbelt on the rails (note this is the one for the right seat). These brackets are on the rails that are facing the door. As it is not bolted, I had to drill out the bracket.
Also from the donor seats: the other rails with the seat belt tensioner has a bolt and a square nut (encircled red) that can be used for mounting the seat belt bracket on the rails. It has some kind of threadlocker, so I used a torch to heat it before loosening the bolt. The square nut fits nicely in the rails of the electric seats.
The bolt encircled in green is what I used for attaching the seatbelt to the bracket. I only had to shorten the bolt about 10 mm.
The picture below shows the mounting bracket bolted on the rails, using the bolt with the square nut. The seat belt now easily attaches to the bracket with the shortened bolt that came from the seat belt tensioner of the donor seat (encircled green).
The Z4M seats are very hard to find in The Netherlands and in Germany and usually go for incredibly high prices. Hence, I looked for alternatives and decided to go for the E46 M3 seats as they offer much more support, specifically the ones with the inflatable bolsters for the lower back + side. On this forum I found some great info regarding the fitting of these seats in an E85, for example the two topics below:
e46 M3 seats in a Z4, will they fit?
E46 M3 seats fitted
After a while, I found a pair of electric E46 M3 Coupé front seats in Germany, near Aachen, which is a couple hours drive from my home. As I wanted to fully test the seats (electric adjustments, seat heating and the inflatable bolsters) I had to bring the Z4. I didn't want to bother anyone by coming along with an extra car to transport the seats since it was a long drive, so I just removed the passenger seat to make space. I installed the M3 seats and tested them on the spot; luckily everything worked fined. For the drive home, I just put the "old" drivers seat on the "new" passenger seat
The E46 M3 seats are so much better than the standard seats! They offer a lot more support and adjustment possibilities, so I am really happy with the upgrade. The looks are also fine for me, even though they look a bit more bulky. I currently have my hardtop installed so I cannot make clear overview pictures, but in the two topics above you will find some good photos.
Some differences I noticed:
- I have the feeling the seat heating is not as warm as the standard Z4 seats, but I didn't measure it so it is hard to tell. Perhaps related to coupe vs. convertible?
- The seat sitting height is higher now, but this is due to electric seats vs. the manual seats I had.
- The seats go a little less far back as they are somewhat wider in the back. Removing the backrest tilt levers already helps, but I find them quite useful as it eases access to the small storage compartments behind the seats. One of the three levers is smaller, so I am currently using this one at the moment for the driver seat, but I will look into 3D printing a small version for both seats.
The seats are plug-and-play as described in the above topics. I should note, however, that I have an early (2003) E85 model which has the wiring for electric seats already installed, despite the fact is was equipped with manual seats. Hence, all electric functionality works without any issues. There are, however, three things to consider:
- I installed the E85 seat belt tensioners on the M3 seats: I have read somewhere that the M3 tensioners might give an error in the E85. My M3 seats came without any belt tensioners, so I had to use the E85 ones anyways. Also, since I was driving without passenger seat, I had to clear the safety error afterwards.
- The E46 M3 seats don't have a seat belt guide near the headrest. Sometimes, this makes it slightly more difficult to grab the belt when buckling up. Also, while driving the belt is near my neck, which is not very comfortable. There seem to be belt guides for E46 models that are mounted to the headrest; not sure if these fit well, but otherwise I will design and print this myself.
- The standard E85 seats have a bracket for the seatbelt on the seat rails. The E46 M3 seats are from a Coupé model, which can tilt forwards to allow passengers to step in the back. Hence, there is no bracket on the seat rails as the seat belt is mounted on the floor/pillar(?). As a temporary solution, I just attached the seatbelt to the rear bolt of the rails (see photo below). However, when moving the seat fully backwards, the seat will slide over the seatbelt, which might cause some damage/wear over time. Also, I didn't really like the construction as the bracket will be loaded under bending during an impact. Already bending it upwards is possible, but this will restrict the backward movement of the seat even more.
Instead, I went out looking for standard E46 seats that have these brackets. I found a pair from some manual seats that were damaged, so I could get the rails for a cheap price. I had to drill out the brackets from the rails on the door-facing side, but could use the bolt and square-nut from the seatbelt tensioner bracket later on for mounting. Below are some photos to further explain this.
If you have any questions or if anything is unclear, let me know
Mounting the seatbelt to the rear bolt of the rails. I only used this as a temporary solution.
From the donor seats: the bracket for mounting the seatbelt on the rails (note this is the one for the right seat). These brackets are on the rails that are facing the door. As it is not bolted, I had to drill out the bracket.
Also from the donor seats: the other rails with the seat belt tensioner has a bolt and a square nut (encircled red) that can be used for mounting the seat belt bracket on the rails. It has some kind of threadlocker, so I used a torch to heat it before loosening the bolt. The square nut fits nicely in the rails of the electric seats.
The bolt encircled in green is what I used for attaching the seatbelt to the bracket. I only had to shorten the bolt about 10 mm.
The picture below shows the mounting bracket bolted on the rails, using the bolt with the square nut. The seat belt now easily attaches to the bracket with the shortened bolt that came from the seat belt tensioner of the donor seat (encircled green).
