2004 BMW Z4 3.0
Discussion
Never really considered a Z4 until I saw this thread on Pistonheads - https://www.pistonheads.com/gassing/topic.asp?h=0&...
I've been after a "fun" convertible for a while - what I really wanted was an E46 M3, but the running costs were a bit too scary considering that this is a meant to be a "sunny day" car and I'm not sure how often I will end up driving it.
I've been keeping an eye out for one for a couple of months, but not really found any in the price range I am looking at anywhere local.
I found one advertised at £4,800 that looked ok, but that was well above what I wanted to spend. It was advertised for quite a while with the price very slowly being reduced. I sent the seller an offer which was initially refused, but then a while later came back to me saying "ok, still interested?".
Net result is that I am now the owner of a 2004 Z4 3.0 with 114,000 miles for £3,400. I'm still not sure if this was a bargain or a terrible idea!
It's in "Merlot red" which to be honest doesn't photograph too well, but having spent a few days with it is really growing on me.
Mechanically it seems in good condition, although the bodywork could do with some tidying.
First impressions are a mixed bag - it feels tiny (in a good way), driving without a roof is a lovely experience, and the engine sounds fantastic.
However, the car seems to tramline quite badly, which doesn't inspire confidence in the bends. Probably related to having runflats.
It also doesn't seem as quick as the stats would suggest - my daily driver is a 200HP diesel so I know I need to get used to the power delivery, but I think I may need to give everything a going over, especially the fabled VANOS.
Either way, I'm looking forward to getting to know it better.
I've just got to remember that this is supposed to be a cheap entry into the world of convertibles and resist the urge to start modifying it...
I've been after a "fun" convertible for a while - what I really wanted was an E46 M3, but the running costs were a bit too scary considering that this is a meant to be a "sunny day" car and I'm not sure how often I will end up driving it.
I've been keeping an eye out for one for a couple of months, but not really found any in the price range I am looking at anywhere local.
I found one advertised at £4,800 that looked ok, but that was well above what I wanted to spend. It was advertised for quite a while with the price very slowly being reduced. I sent the seller an offer which was initially refused, but then a while later came back to me saying "ok, still interested?".
Net result is that I am now the owner of a 2004 Z4 3.0 with 114,000 miles for £3,400. I'm still not sure if this was a bargain or a terrible idea!
It's in "Merlot red" which to be honest doesn't photograph too well, but having spent a few days with it is really growing on me.
Mechanically it seems in good condition, although the bodywork could do with some tidying.
First impressions are a mixed bag - it feels tiny (in a good way), driving without a roof is a lovely experience, and the engine sounds fantastic.
However, the car seems to tramline quite badly, which doesn't inspire confidence in the bends. Probably related to having runflats.
It also doesn't seem as quick as the stats would suggest - my daily driver is a 200HP diesel so I know I need to get used to the power delivery, but I think I may need to give everything a going over, especially the fabled VANOS.
Either way, I'm looking forward to getting to know it better.
I've just got to remember that this is supposed to be a cheap entry into the world of convertibles and resist the urge to start modifying it...
TwoStrokeNut said:
It'll look a lot better with silver wheels though, as the black does clash a bit.
The wheels are growing on me (mainly as they are freshly refurbed) but I really want the Ellipsoid wheels instead.TwoStrokeNut said:
It'll ride much better on non-runflats. Also it'll probably need some new shocks and bushes, rear RTAB in particular.
Considering the mileage it drives quite well. At some point I need to give it a proper check over. I'm trying to avoid refreshing the suspension as I have a habit of taking these things too far...TwoStrokeNut said:
It'll ride much better on non-runflats. Also it'll probably need some new shocks and bushes, rear RTAB in particular.
Enjoy!
Enjoy!
SouthHamsGaz said:
Check the front lollipop bushes, they are the usual cause of tramlining, along with RFL, if they are shot then the wishbones are probably not far behind.
Even though this is meant to be a sunny-day car, with the weather recently I hadn't driven my daily driver (RenaultSport Megane) since I bought it.When I finally drove the Megane again it made me realise that the Z4's steering is all over the shop - at high speeds it seems to have a mind of it's own!
With that in mind I thought I'd work through some of the obvious causes.
Firstly - front wishbone bushes
Out with the old (one side was original, the other 10 years old)
Got the bush out easy enough but struggled to get the metal collar out without a suitably sized driver to push it out with
Came across a suggestion online to use a hacksaw blade to cut through it and then you can crush it out which worked a peach, just took a bit of time
Back together with Powerflex bushes. The old bushes were obviously less stiff but didn't seem loose or overly worn.
While there I also replaced the front anti-roll bar bushes.
Back together and to be honest - it was worse! The front end feels more agile - but with the front end being quite darty at speed this just exacerbates it.
Next then, rear trailing arm bushes (RTAB)
Dropped the trailing arm down - found this a bit harder than guides online suggested as there was various pieces of trim to remove before you could actually drop it all the way down.
I'm using 10-ton hydraulic puller to remove the bushes, and even then I really really struggled to get them out - although they made a satisfying "bang" when they started moving! Glad I have this tool as the threaded-bar tools off eBay wouldn't of done a thing.
Again replaced with Powerflex bushes. The old ones seemed fine though...
Back together and... still bad!
I've been reading up and my guess is the steering system next. Runflats at the front aren't helping but I'm loathed to chuck a pair of premium tyres in the bin when they have plenty of tread.
I also got to give the car a good going over and I was pleasantly surprised by what I found - all the rear bushes are looking good, no broken springs, engine mounts seem solid, brakes look good etc. Only issues are a broken exhaust mount and a potential oil leak.
Spacers were also mentioned - the car already has 15mm front / 20mm rear spacers fitted, and longer wheel bolts to suit.
Not my usual thing but having got used to how it looks now, it would probably look weird if I took them off.
Also retrofitted cruise control
On pre-facelift models all the wiring is already there, so it's just plug and play. Stalk was £110 from a dealer so not cheap, but worth it.
I enabled "comfort access" so that I can open the roof from the key remotely - https://youtu.be/BPdjZO5Oqe0 - it's not as neat as some of the aftermarket modifications to do the same thing (i.e. not one touch) but for free I'm chuffed.
First tank of fuel averaged 32MPG which I think is very good for an old 3.0 6 cylinder petrol.
Edited by Jakg on Monday 30th July 01:12
helix402 said:
Have you had the wheel alignment (4 wheel) done with the new bushes?
Not yet. That's the other thing on the list. The plan was to wait until the suspension was "done" before I did it.Jez m said:
New steering rack bushes and a full alignment sorted out my old Z4's 'nervous' and darty feel. Mine was on non-run flats too.. that made the biggest difference of all to the handling.
Steering rack bush?Welcome to my not-a-project car that I'm definitely not modifying.
Fitted a dashcam. Went for the lazy option and wired it into the wiring for the rain sensor as it's on an ignition live.
Took the DISA valve out and cleaned it up, but hasn't made a difference to performance. I think with all the use it's got that it's loosened up a bit, but still doesn't quite feel 230HP. VANOS is a job for the winter I think.
Gearknob was in a state so got a new one. Couldn't get a ZHP one (OE BMW sport one) from a dealer in the UK, but found a slightly cheaper one on eBay from Bulgaria. Turned up in a BMW box, but was a fake (incorrect weight). Seller said they had no idea, but immediately sent a refund without checking anything... suspicious. Fitted it anyway and it's ok. Will probably get the real deal later.
Bought a strut brace off eBay as it was cheap. When it turned up it was suspiciously light (<3KG). I had a look at the sellers other items and they've since relisted more of them with a description of "no idea what car this fits". Good start.
Unsurprisingly, doesn't fit!
Engine is nothing special to look at, but having only owned transverse engined cars every time I open the bonnet I'm immediately reminded how long it is!
Replaced the broken exhaust mount that I noticed the other day, only to realise there's actually two for the backbox. And the other is broken. So that's another job. At least they are only £9.
While I had it jacked up I also fitted some Powerflex rear anti roll bar bushes, and removed the clutch delay valve.
Had the alignment done and it's improved the handling quite a bit.
Unfortunately the garage have used the wrong settings (sport vs non-sport suspension). They also said that the front camber isn't adjustable (or more precisely, is adjustable but never works). Having looked it up online you just drop a pin out and move the strut tops in the oversized holes. Not sure how that can "not work".
Tramlining has reduced, but on the other hand the stiffer bushes have made it sharper which makes it more apparent. Will spend some more time driving it and think about what next to improve it. I also noticed that three of the tyres are Bridgestone Runflats, and one is a Landsail non-runflat (don't know how I missed that!) which definitely won't be helping!
Ran the car through one of those VIN decoders and it turns out it's got quite a few optional extras.
The good news is that it's a got a fancy 10-speaker stereo system.
The bad news is that it's got a fancy 10-speaker stereo system, with a cutting edge digital link from the headunit to the amplifier in the boot... in 2004.
Tried swapping out the headunit but while a new one powers up, no sound comes out of the speakers as it's not sending the output to the amplifier via KBUS.
The only solution appears to be to replace the amplifier in the boot with an aftermarket one, and do the crossovers for each speaker yourself.
On the plus side, at least the amplifier is near the battery.
2 tanks in and it's averaging 32MPG which isn't too bad.
Fitted a dashcam. Went for the lazy option and wired it into the wiring for the rain sensor as it's on an ignition live.
Took the DISA valve out and cleaned it up, but hasn't made a difference to performance. I think with all the use it's got that it's loosened up a bit, but still doesn't quite feel 230HP. VANOS is a job for the winter I think.
Gearknob was in a state so got a new one. Couldn't get a ZHP one (OE BMW sport one) from a dealer in the UK, but found a slightly cheaper one on eBay from Bulgaria. Turned up in a BMW box, but was a fake (incorrect weight). Seller said they had no idea, but immediately sent a refund without checking anything... suspicious. Fitted it anyway and it's ok. Will probably get the real deal later.
Bought a strut brace off eBay as it was cheap. When it turned up it was suspiciously light (<3KG). I had a look at the sellers other items and they've since relisted more of them with a description of "no idea what car this fits". Good start.
Unsurprisingly, doesn't fit!
Engine is nothing special to look at, but having only owned transverse engined cars every time I open the bonnet I'm immediately reminded how long it is!
Replaced the broken exhaust mount that I noticed the other day, only to realise there's actually two for the backbox. And the other is broken. So that's another job. At least they are only £9.
While I had it jacked up I also fitted some Powerflex rear anti roll bar bushes, and removed the clutch delay valve.
Had the alignment done and it's improved the handling quite a bit.
Unfortunately the garage have used the wrong settings (sport vs non-sport suspension). They also said that the front camber isn't adjustable (or more precisely, is adjustable but never works). Having looked it up online you just drop a pin out and move the strut tops in the oversized holes. Not sure how that can "not work".
Tramlining has reduced, but on the other hand the stiffer bushes have made it sharper which makes it more apparent. Will spend some more time driving it and think about what next to improve it. I also noticed that three of the tyres are Bridgestone Runflats, and one is a Landsail non-runflat (don't know how I missed that!) which definitely won't be helping!
Ran the car through one of those VIN decoders and it turns out it's got quite a few optional extras.
The good news is that it's a got a fancy 10-speaker stereo system.
The bad news is that it's got a fancy 10-speaker stereo system, with a cutting edge digital link from the headunit to the amplifier in the boot... in 2004.
Tried swapping out the headunit but while a new one powers up, no sound comes out of the speakers as it's not sending the output to the amplifier via KBUS.
The only solution appears to be to replace the amplifier in the boot with an aftermarket one, and do the crossovers for each speaker yourself.
On the plus side, at least the amplifier is near the battery.
2 tanks in and it's averaging 32MPG which isn't too bad.
Edited by Jakg on Wednesday 24th August 10:03
TwoStrokeNut said:
A chap on the z4 forum did some audio spectrum analysis on the carver unit.
https://z4-forum.com/forum/viewtopic.php?f=2&t...
Try his settings. My sound went from pretty terrible to acceptable using those.
With the basic "business" head unit, you can't adjust those settings unfortunately.https://z4-forum.com/forum/viewtopic.php?f=2&t...
Try his settings. My sound went from pretty terrible to acceptable using those.
5harp3y said:
or get the right connector from Connect2 (Recently did this to fit an aftermarket HU to my wifes 1 series)
There is no such adaptor to make this work - the amp requires a digital signal which no aftermarket HU providesTwoStrokeNut said:
Hmm, that's weird. What DSP settings can you change?
Without the Nav screen, I think I would junk all of the factory kit and install an aftermarket headunit and amp in the stock location. Get a circuit diagram and you should be able to reuse some of the wiring.
You can select three DSP modes, and that's it!Without the Nav screen, I think I would junk all of the factory kit and install an aftermarket headunit and amp in the stock location. Get a circuit diagram and you should be able to reuse some of the wiring.
I'm leaning more towards a new amp..
Jakg said:
Unfortunately the garage have used the wrong settings (sport vs non-sport suspension). They also said that the front camber isn't adjustable (or more precisely, is adjustable but never works). Having looked it up online you just drop a pin out and move the strut tops in the oversized holes. Not sure how that can "not work".
They were however insistent that the settings were the same between sport vs non-sport suspension, when I brought up AutoData they dismissed this as Hunter's settings are direct from the manufacturer.
Having done some more research, definitely not the same settings - but it turns out that they have aligned it to the correct ones anyway - i.e. they simply didn't notice the settings had changed - you can see the difference between allowed camber ranges between the two printouts.
The fact they didn't spot this, or that a car that had an alignment a week ago was suddenly red all over I have no idea. Not used them before for alignment and not sure if I would again - shame as they are local and have the proper Hunter gear.
Working through the service history and the last recorded pollen filter was several years ago. When I pulled it out it's clearly been done recently - I changed it anyway as I had it out but it appears the cars been looked after properly.
In the middle of changing the VANOS seals at the moment... not a fun job on an E46, let alone on a car with a much smaller engine bay.
Jakg said:
In the middle of changing the VANOS seals at the moment... not a fun job on an E46, let alone on a car with a much smaller engine bay.
The car seems to be getting through oil quite quickly. From underneath I could see oil on the engine so at least it's not burning it, although through the vents with the blowers on you could smell burning oil which points to oil leaking onto the exhaust and burning off there.The car seems down on power (but coming from a turbo diesel with similar power, but more weight, makes it difficult to tell!) and a common cause is the seals on the VANOS unit wearing out (VANOS = BMW's variable valve timing system). The OE seals are made from the "wrong" kind of rubber and as such don't last.
Removing the VANOS unit requires replacing the valve cover gasket which is the most common source of oil leaks on the M54 engine so I thought I'd kill two birds with one stone.
Although I only need a couple of seals for the VANOS unit, I bought a complete kit from X8R that includes various other seals and gaskets that get disturbed along the way. Not cheap at £80, but very comprehensive.
VANOS removal is well-trodden for the E46 but on the Z4 it's significantly harder as there's just no room to work in.
A panel comes off the top of the radiator to give a little access to the front of the engine to get to some of the bolts. I managed to do it without removing the fan, but cut my hands to bits in the process.
Covers off
Coils and wiring out of the way
Valve cover off
The VANOS unit are the two spheres to the right of the cam chain.
The space between the front of the engine and the bulkhead was so small that I couldn't even fit a ratchet in at some points. It's mounted using studs and one stud was slightly too long such that the VANOS unit won't clear it before getting stuck on the bulkhead - ended up having to move the unit forward and then unwind the stud using molegrips.
In addition the housing for the coolant temp sensor fouls the VANOS unit so that has to come out too, meaning some coolant is lost.
Lots of effort later
Dismantled the VANOS unit and replaced the piston seals. The existing seals were rock-hard.
Put it all back together, but when topping up the coolant I noticed it was a nice brown-rust colour. Don't think it's been changed in a while, will have to add to the list.
It's too early to say if it's fixed my oil leak, but having replaced the valve cover gasket I don't appear to have introduced any new major oil leaks which I suppose is a success in itself having never tackled anything "engine-y" like this before.
Performance seems the same, though - the seals take some time to "bed in" but perhaps I need to adjust my perception too.
"Bedding in the seals" was a good excuse to take it out, though.
Headlights have been letting the front down, gone all cloudy.
Used one of the 3M kits to bring it back. The first step involves some quite abrasive material which always makes me think "What have I done!" as it takes your slightly-crazed headlights and makes them look like they've been sandblasted.
Through the rest of the steps and I ended up with this
Much better. Won't last forever, but not bad for an hours work and £20.
Used one of the 3M kits to bring it back. The first step involves some quite abrasive material which always makes me think "What have I done!" as it takes your slightly-crazed headlights and makes them look like they've been sandblasted.
Through the rest of the steps and I ended up with this
Much better. Won't last forever, but not bad for an hours work and £20.
My car has the standard seats, and they are useless. Leather, and quite comfy, but with absolutely no lateral support. Going round corners you had to try to hold yourself upright in the seats.
An easy upgrade is the sports seats from a Z4, but these are very expensive second hand (£1k!). Alternatively, E46 seats are supposed to be a drop in replacement, but I wasn't keen on the look of M3 ones.
I found someone had made up S2000 seats by making adaptor plates up and thought I'd give it a go - but with a twist.
I've always like the Corsa VXR Recaro seats and supposedly (incorrectly, it turns out) they should fit in my Megane if I couldn't fit them here, so I picked up a set. Because they are common they are quite a bit cheaper than you'd expect - I paid £350.
I then picked up another set, because why not. Good job I just finished extending my spare bedroom...
Made adaptor plates up out of 6mm steel. The S2000 seats I'd seen fitted used box section, but I knew that the height of the seat would be an issue so I had to do everything possible to keep them low.
Many grinder discs and drill bits were sacrificed.
I couldn't work out how to use the electric seat runners from the Z4 seats, so decided to use the Corsa runners instead, but they needed quite a bit of modification.
Using the Corsa runners means everything still works, inc the button to fold and slide the seats forward.
I'm aware I'm no pro fabricator...
The channel in the runners was so narrow I even had to grind the nuts down a tad to clear it
Out with the old
In with the new
The good:
The seats are ace.
No less comfy than the standard seats, but so much more supportive.
The car actually feels like it handles better too, probably because you are better connected to what the car is doing.
The bad:
The seats are much bigger than the Z4 ones, which are actually tiny. The Z4 doesn't even have seat airbags - they are in the doors instead.
Because they are bigger, they don't go back as far - but luckily they go just as far back as I need them.
They sit a little higher than the Z4 seats.
However, I think I would've had these problems with any other non-Z4 seats.
An easy upgrade is the sports seats from a Z4, but these are very expensive second hand (£1k!). Alternatively, E46 seats are supposed to be a drop in replacement, but I wasn't keen on the look of M3 ones.
I found someone had made up S2000 seats by making adaptor plates up and thought I'd give it a go - but with a twist.
I've always like the Corsa VXR Recaro seats and supposedly (incorrectly, it turns out) they should fit in my Megane if I couldn't fit them here, so I picked up a set. Because they are common they are quite a bit cheaper than you'd expect - I paid £350.
I then picked up another set, because why not. Good job I just finished extending my spare bedroom...
Made adaptor plates up out of 6mm steel. The S2000 seats I'd seen fitted used box section, but I knew that the height of the seat would be an issue so I had to do everything possible to keep them low.
Many grinder discs and drill bits were sacrificed.
I couldn't work out how to use the electric seat runners from the Z4 seats, so decided to use the Corsa runners instead, but they needed quite a bit of modification.
Using the Corsa runners means everything still works, inc the button to fold and slide the seats forward.
I'm aware I'm no pro fabricator...
The channel in the runners was so narrow I even had to grind the nuts down a tad to clear it
Out with the old
In with the new
The good:
The seats are ace.
No less comfy than the standard seats, but so much more supportive.
The car actually feels like it handles better too, probably because you are better connected to what the car is doing.
The bad:
The seats are much bigger than the Z4 ones, which are actually tiny. The Z4 doesn't even have seat airbags - they are in the doors instead.
Because they are bigger, they don't go back as far - but luckily they go just as far back as I need them.
They sit a little higher than the Z4 seats.
However, I think I would've had these problems with any other non-Z4 seats.
Edited by Jakg on Wednesday 24th August 10:06
First MOT in my ownership - failed on corroded brake pipes, which was an advisory before so not too bad.
Garage replaced them and at the same time got them to replace all the fluid with ATE Type 200, and all the bleed nipples with some new stainless HEL ones as the existing ones were starting to round.
An advisory on worn ball joints so did those, too.
Annoyingly on my Megane a front balljoint is £15 and can be pressed in and out of the arm in situ. On the Z4 you need a whole new arm (£64) - although I went for Meyle HD arms where the balljoints are replaceable in the future (but they are still £30).
Access to the middle bolts on the arm was quite tricky, from the bottom you've got 1/8th a turn max using a spanner, and from above you need to use a bunch of extensions & UJs
The other side access was even worse, which was annoying as rust had made the bolt mega-tight - you can just about make out the nut next to the engine mount.
Even went to Halfords to get some wobble extensions, but just couldn't line it up, so spanner it was - the force of undoing it has literally made my hand swell!
Got them out in the end though
When I changed the wishbone bushes, I was a bit lazy and didn't bother lining the carrier up over the collets on the chassis properly, just started doing the bolts up and thought it'd bring the carrier home on it's own. Nope, it just damaged the threads as it wasn't lined up right...
The top bolt did start to tighten but it then it started to get looser again and that's when I knew I'd done it. Left it at the time but I knew I had to fix it.
Borrowed a Helicoil kit and although I was a bit terrified it turned out ok in the end.
My suggestion is to loosely insert the ball joints first, put the nut on but don't tighten at all. Then get the bush lined up properly over the collets, and put the bolts in tight enough to keep it on them, but loose enough it can move. All the guides say to do the bushes last - but then you end up with very little play so it's a real pain to line up (which was why I rushed it last time).
Note I said the *top* one was worn out. I forgot that and drilled out the perfectly good bottom one first, oops.
Torqued up fine though the second time round so alls well.
My assistant wasn't much help either.
Some of the "vagueness" in the steering has gone and the tramlining has reduced a little too which is good. Now need to work out if I want to get it aligned again (would be the third time in less than a year...)
Garage replaced them and at the same time got them to replace all the fluid with ATE Type 200, and all the bleed nipples with some new stainless HEL ones as the existing ones were starting to round.
An advisory on worn ball joints so did those, too.
Annoyingly on my Megane a front balljoint is £15 and can be pressed in and out of the arm in situ. On the Z4 you need a whole new arm (£64) - although I went for Meyle HD arms where the balljoints are replaceable in the future (but they are still £30).
Access to the middle bolts on the arm was quite tricky, from the bottom you've got 1/8th a turn max using a spanner, and from above you need to use a bunch of extensions & UJs
The other side access was even worse, which was annoying as rust had made the bolt mega-tight - you can just about make out the nut next to the engine mount.
Even went to Halfords to get some wobble extensions, but just couldn't line it up, so spanner it was - the force of undoing it has literally made my hand swell!
Got them out in the end though
When I changed the wishbone bushes, I was a bit lazy and didn't bother lining the carrier up over the collets on the chassis properly, just started doing the bolts up and thought it'd bring the carrier home on it's own. Nope, it just damaged the threads as it wasn't lined up right...
The top bolt did start to tighten but it then it started to get looser again and that's when I knew I'd done it. Left it at the time but I knew I had to fix it.
Borrowed a Helicoil kit and although I was a bit terrified it turned out ok in the end.
My suggestion is to loosely insert the ball joints first, put the nut on but don't tighten at all. Then get the bush lined up properly over the collets, and put the bolts in tight enough to keep it on them, but loose enough it can move. All the guides say to do the bushes last - but then you end up with very little play so it's a real pain to line up (which was why I rushed it last time).
Note I said the *top* one was worn out. I forgot that and drilled out the perfectly good bottom one first, oops.
Torqued up fine though the second time round so alls well.
My assistant wasn't much help either.
Some of the "vagueness" in the steering has gone and the tramlining has reduced a little too which is good. Now need to work out if I want to get it aligned again (would be the third time in less than a year...)
dave_s13 said:
The e93 doesn't tramline at all though, doesn't that do your nut in?
Yes! Not my daily driver, and not something I'd choose for a long motorway journey so I'll tolerate it.I've got a new pair of (non-runflat) tyres in the shed but I feel silly putting them on as the runflats on the front still have >4mm.
Hopefully that should cure it.
SamJB said:
Fitting the larger front anti roll bar off of an E46 M3 made a huge difference for me, you can pick them up for peanuts from ebay and they'll bolt right up.
It looks like only the front fits, not the rear - I'm wary of stiffening up the front at the expense of increasing understeer. Not that I have a problem with that at the moment.Edited by Jakg on Tuesday 5th March 17:26
Jakg said:
I've just got to remember that this is supposed to be a cheap entry into the world of convertibles and resist the urge to start modifying it...
I’ve always been contemplating a brake upgrade.As standard it has 300mm discs and single-piston calipers at the front
Looked a bit weedy for a 155MPH car. My diesel Megane has Brembo 4-piston calipers from the factory!
There were a couple of routes available:
1 - E46 330i / Z4 3.0si 325mm
Straight fit, easily available, but because of their popularity the carriers + calipers sell for about £100
I’ve done this upgrade on my old MG ZT (it uses E46 brakes) in the past as was impressed.
But they are still single-piston and I thought maybe I could try something different.
2 - E82 135i 6-pot
I liked this idea, but simply couldn’t find any. They were only ever fitted to the E82 135i, which isn’t that commonly broken.
3 - Porsche Brembo Calipers + Brackets
Much more like it, but the brackets aren’t cheap and the popularity means the calipers aren’t either.
4 - F30 M-performance Brembo Calipers
Came across someone fitting them to an E46 - https://forum.e46fanatics.com/showthread.php?t=107... and piqued my interest - bolt on and eaily available.
Picked these up for a little over £200 because they’d been painted red absolutely terribly.
After some wire wheel action it turns out they are supposed to be silver.
Because they are only a few years old they were in very good condition.
I also got a spare set of rear calipers to refurb.
This was harder than it sounds, because there are a handful of calipers or carriers used on E46/Z4s, but in various configurations. I think it ended up being something daft like an 02-04 325i/328i but nothing else fitted!
Being about 15 years old they were in way worse condition, rust etc. I tried a wire wheel and my ultrasonic cleaner but it wasn’t making much difference.
Ended up trying electrolysis - https://www.the75andztclub.co.uk/forum/showthread....
The layer of scum and slime that formed on top was absolutely disgusting.
They didn’t come out perfect, but most of the rust was easily removed after.
The car had red calipers fitted which I’ve never thought was a great look on a dark-red car.
I’ve spray painted calipers in the past but never really been happy with the finish, so I tried a different kind of kit this time, from BCS Autotmotive - https://www.bcs-automotive.co.uk/shop/brake-calipe...
Went for gunmetal, this is the ad picture…
Primed
First coat
Second coat
Thought they looked a bit weird plain so went for some stickers. I know this will be divisive!
From the factory they can come as part of the “M Performance Brakes” pack with the //M sticker so I don’t feel *too* bad about it.
They are supposed to be upside down (or at least, thats how BMW do it) on one of the calipers.
Lacquer over the top and then baked
Unfortunately - disaster
I think some brake fluid leaked out while in the oven and ate off the paint. Luckily as it’s brush-on, localised repairs were very easy.
I overhauled the rear calipers (seals, dust boots, sliders, slide bushes), but left the fronts as they were so new.
Overall the kit wasn’t cheap, especially not when I had to buy primer and lacquer on top. And being a brush-on kit, you get brush marks. That works ok for a metallic gunmetal finish, but for a flatter colour I doubt it would. Not sure what I’d do next time!
Then it was fitting time.
Straight off the bat I had problems, the disc retaining screws both rounded off despite doing everything properly.
Ended up using a chisel to tap them out.
I’m using 345mm Z4M / E46 M3 CSL front discs. I got a second hand set in case they didn’t fit as they are quite pricey. I’ll try to get a new set later on.
The pad retaining pins I’d bought didn’t fit so I had to use the original ones - note how the (new) top pin hasn’t gone across anywhere near as far as the (old) bottom one
It didn’t have a chamfer on the end so it didn’t lock in place, either.
I initially used F30 brake hoses as per the guide but the length was too long and the grommets weren’t right so I get a set made up by HEL.
I couldn’t get the rear hoses fitted properly as the unions on both sides were totally seized and just rounded off.
Ended up replacing the whole lot with braided hoses at the back, too.
When reassembling I accidentally torqued the rear carriers up to 110nm (as per the fronts), not 65nm, so needed new bolts, too. Luckily they came out without too much hassle.
When trying to bleed the brakes my Eezibleed started leaking again (this is my second, and has already had new o-rings to combat the last leak!).
I splashed out on a a Sealey bleeder - half the reviews said it was fantastic, half said it leaked. Mine turned up and leaked - until I found a tip online to put silicone grease around the cap and it was fine. Way easier than trying to deflate a spare tyre to the right pressure.
Flushed another litre of ATE Type 200 brake fluid through and bleed the clutch as well in case I had any contaminated fluid.
I had to fit larger spacers than I’d like to clear the calipers
I had a horrible moment when I put the wheels back on as they stuck out miles!
Luckily when back on the wheels it turned out ok, but I will look into ways to bring them in a bit
Only fitted them the other day so rubbish pictures. A little too early to give lots of feedback - but they do at least work!
Edited by Jakg on Wednesday 24th August 10:07
Jakg said:
I've just got to remember that this is supposed to be a cheap entry into the world of convertibles and resist the urge to start modifying it...
This really isn't going well!It's got standard M-sport suspension, but is 15 years old. It could do with a refresh, but a Bilstein B8 kit is about £600, and OE parts even more so.
I found this on eBay and knew I had to get it.
KW V1 coilovers, about 4 years old - £1,200 RRP! I got them for a fifth of that.
First off, big shout out to my latest toy - a big battery impact gun.
I've tried some cheap Lidl ones and they were... ok. I use a Bosch impact driver a lot but it doesn't have the power to crack stuff off. This thing claims 1600nm of torque so I shouldn't have that problem...
The shock bolt looks looked like it might be a problem, but came out with no effort at all.
In fact getting all the old suspension out was very very easy - way easier than my Megane. Only annoyance was having to remove the rear "parcel shelf" to get to the rear shocks which is very awkward from inside the boot.
Out with all the old stuff.
With the suspension out I also had a look at the rear arm mountings - the thing the socket is on in this picture
They didn't seem to have any play on the car but I changed them anyway.
Officially you need to remove the arm but if you bend back the dust shield (and remove the disc obviously) you can get to them.
I've done this in the past on my MG ZT and really struggled - the threaded rod + washers did nothing and I had to use my hydraulic puller.
This time there wasn't enough access for the puller so I had to settle for my ball joint press - basically a big C clamp. 32mm 12-point socket as a pusher and a bit of tube on the arm itself.
It was a bit of a struggle, ended up using the impact gun to get them in / out and i'm not sure the press would do it again but got them all out.
The upper mountings are ball joints (on the left in the picture).
The lower ones are just rubber bushes (on the right).
The M3 / Z4M uses the ball joints on the lower, too - but the rest of the Z4 / E46 range don't, apparently for cost reasons.
Off the car it was clear the ball joints had a little play and the bushes looked past their best.
I fitted ball joints in both the upper and lower parts, and fitted them using the press in reverse.
Don't look exciting fitted though.
I also fitted rear strut reinforcement plates, although I'm not sure if they are any good
My assistant has a lot to learn
All back fitted
I replaced most of the nuts and bolts I touched, too, as well as the top mounts.
I also had a go at adjusting the handbrake as I had to wind the shoes back when I took the disc off and didn't count how far I'd done it - it's a little better now but it's still rubbish. I think the mechanism on one side might need an overhaul.
Had it aligned and everythings back to where it should be, except the rear camber that won't adjust on one side - I had a go (to try at least put it back to what it was before) when I was putting it together and couldn't do it, either. So I'll get a new eccentric bolt / nut etc and try it again.
I also managed to get into an argument at the garage as apparently the rubber bushes at the back keep moving when they tried to free off the camber bolt.
I explained they are ball joints, but apparently they aren't - they are rubber bushes. They helpfully pointed out ball joints have a ball in them and move around.
What would I know, I only fitted the things...
Ride height wise my aim is basically stock - I've had a go but need to let it settle before finishing it off.
Early days but it drives better - I was expecting horrible stiffness but it rides better than my Megane on stock (refreshed) suspension.
Edited by Jakg on Tuesday 29th October 22:19
Boring update:
When I got the car I used a simple vent mounted phone holder. It was rubbish and fell off all the time.
Fitted a Brodit mount instead - not cheap but holds it perfectly steady.
I also fitted a USB charger in the dash and ran a wire out to charge my phone in addition to the USB socket the previous owner put on the centre console.
Also fitted an LED strip in the boot as the boot light is rubbish.
Also refurbished the DISA valve with one of the kits - not convinced the risk as great as quoted but it wasn't expensive.
Struggled to remove the old plastic parts and ended up drilling them out - pillar drill coming in handy again!
When I got the car I used a simple vent mounted phone holder. It was rubbish and fell off all the time.
Fitted a Brodit mount instead - not cheap but holds it perfectly steady.
I also fitted a USB charger in the dash and ran a wire out to charge my phone in addition to the USB socket the previous owner put on the centre console.
Also fitted an LED strip in the boot as the boot light is rubbish.
Also refurbished the DISA valve with one of the kits - not convinced the risk as great as quoted but it wasn't expensive.
Struggled to remove the old plastic parts and ended up drilling them out - pillar drill coming in handy again!
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