Montego Blue E86 is Long Gone - Z4MC Diff Rebuild

[lucasxdiniz]

Hi Lucas,

How are you finding you BC suspension? Thinking of changing mine when I do all my brakes and bushes over the winter

Cheers
Matt

Hi Matt,

I'm still quite happy with the BCs. Can't imagine better value for what you get. Only (non)issue one might have is the noises from the solid mounts that can be transmitted through the chassis - it can sound like something is loose when you're driving slowly over really bumpy roads. However, I found this is greatly amplified by the 3-point strut brace I have, without the brace they're only slightly noisier than OE mounts would be.

Comfort is just as good as OEM with the damping at around 18 clicks front and 15 rear. And this is how they look after 15k miles, including a lot of salty roads driving last winter. Photos taken last week after I detailed the car (arches and BCs are dry).

[Weston Matt]

Thanks Lucas, very informative.

Think I will push the button. My B4s and eibach only have about 7000 on them, so should be able to get some for them

[lucasxdiniz]

Thanks Lucas, very informative.

Think I will push the button. My B4s and eibach only have about 7000 on them, so should be able to get some for them

For reference, mine had around 10k when I sold them for £300 I think.

Edit: I think it was more like £350 posted and fully assembled with top mounts that were 10k old as well.

[Weston Matt]

Cheers Lucas.

[lucasxdiniz]

No updates about the car for the time being, but some maintenance will be done soon as I'm currently awaiting a delivery from AutoDoc. However, I finally got a side project done.

Back in April I found a 1:24 Montego Blue E86 model and bought it with the intention on making it as similar to my car as I could.

First thing was to lower the model and then see how I could change its wheels...



I couldn't find a Z4 model with 108s, so ended up modelling my own and printing them in resin. Unfortunately some compromises had to be made so I could get as much detail as I could while not getting something that would break incredibly easily (it's near enough though):



And after changing the wheels and making some scaled plates:







Quite pleased with it (the photos don't make it justice as all defects stick out). Soon I'll paint the interior to match mine and re-do the plates as they're not perfect and somehow paint BMW badges on the wheel centres.

[lucasxdiniz]

Recently the car has received a lot of attention with several preventive maintenance items ticked off. I planned to do the cam cover gasket over Christmas but managed to accidently order the N52 gasket, which does not fit the N52K. So started off the first weekend into the new year doing a cam cover replacement, and while there, I also replaced the eccentric shaft sensor and its gasket for good measure.

It was great to see how clean my engine is and how there isn't any noticeable wear anywhere in the cams.




For months I had been very aware of how much play my shifter had, so I wanted to rebuild it. Always put it off as the exhaust needs to be dropped and I knew the studs would not be something I could tackle in my garage with no electricity. So 1.5hrs of labour from StyleDynamics later, the studs had been removed and a set of fixings put in their place.

I ordered all the parts from Cotswolds Chelterham BMW for about £85 in total shipped.



Here's the before:



Here's the after:



I expected the play to be reduced to 2-3mm and to be an overall improvement, but definitely was surprised to find that there is no play in the shifter now and the feel is tremendously improved across all gears. I also bled my clutch slave cylinder prior to the rebuild and that made no difference - apart from the good feeling of knowing there's no dirty fluid in the clutch lines of course!

And today I flushed the coolant and replaced the expansion tank with a new one I had bought in 2019 for my E85. I've heard so many bad things about aftermarket ones since then, that I was reluctant to put the aftermarket one I had available, but I had nothing to lose but a couple of hours max, so decided to try it anyway. I'll try and dig up the link for the one I bought in 2019 because I had zero fitment issues or concerns about its quality (both seem to be a commonly brought up in the forum). I also found the job very straight forward, just don't be afraid to cleverly leverage the bottom hoses off (the only ones that wouldn't come off with a bit of pulling). I would suggest removing all the connections but the bottoms ones, then place a screwdriver between the bottom fittings propping it against the tank itself and it comes right up!





Oh yeah, two new rear tyres and all wheels re-balanced. Made me realise that one or more of my wheels was slightly unbalanced as a slight vibration over 60 mph is totally gone. Happy days.

[1536Z4]

Happy days.

Good to see you still enjoying the coupe and great news on the condition of the engine Let me know when you want to sell that LSD

[lucasxdiniz]

I thought I would change the rear trailing arm bushes as I thought they could be tired after so many miles and they're the only major suspension component in my car that hasn't been replaced. I bought a tool to do the job and it was quite straight forward, about 2hrs overall if I discount all the cleaning and painting.

Old vs new - old looks a bit mangled after I took it off, but in reality it was absolutely fine.




After replacement I gave everything a good clean and painted the trailing arm to remove the surface rust:



I also got my skirts re-sprayed as the ends in both sides had loads of stone chips and one side had a scratch from something I almost ran over a few months ago. Really happy with the colour match, and surprised by how noticeable it is (to me) the difference it made to the car.



Once the skirts were off, I obviously cleaned and waxed everything I could!




And the finished product:



I don't really have anything else I need or can do the car as it's great and I've done all preventive maintenance one could do. Next job is going to be a brake fluid flush as I do this every 6 months (Motul 660)/before driving season but this time I will replace all the calliper nipples are they're getting a bit rounded.

[Z450]

Impressive, great work and your Coupe looks

[LemonConnoisseur]

Excellent thread Lucas, a lot of the things you've done to your Coupe is along the same lines of what I'd like to do to mine.

A question on the sound deadening mat in the boot, did you heat it up to follow the contours of the metal?
Since getting a new backbox made up, it's noticeably louder in the car so I've bought some mats, but I'm questioning where to put it, and also whether the carpet is going to fit back in the same place.

Any future plans for the car?

[lucasxdiniz]

Excellent thread Lucas, a lot of the things you've done to your Coupe is along the same lines of what I'd like to do to mine.

A question on the sound deadening mat in the boot, did you heat it up to follow the contours of the metal?
Since getting a new backbox made up, it's noticeably louder in the car so I've bought some mats, but I'm questioning where to put it, and also whether the carpet is going to fit back in the same place.

Any future plans for the car?

Thank you.

No need to heat it up, just have a roller or a nice and flat trim tool to help you contour the sound deadening mats to the surface. One layer shouldn't really stop any of the trim and carpet from sitting in the right place.

I have several plans for my car, none of which are affordable to me at the moment. Being a powertrain design engineer, I'd love to 3D scan the engine bay and properly design an installation for a S65 swap, for example.

[Andy Tate]

Very clean looking car. I love the miniature version also is it originally from hot wheels? I may get one for my son to play with.

[grannyknot]

I don't know how I missed this thread but just read it front to back, outstanding work and detail! A pleasure to read through on a Saturday morning with a big coffee.
I'm about to do something very similar to my coupe, mine is Sapphire black and I'm okay with that but would much rather have that shade of blue.
Keep up the good work.

[lucasxdiniz]

Very clean looking car. I love the miniature version also is it originally from hot wheels? I may get one for my son to play with.

Thank you. No, it's a 1:24 model from Schuco. I have two hotwheel models of an E86 GTS race car, which is easily found.

I don't know how I missed this thread but just read it front to back, outstanding work and detail! A pleasure to read through on a Saturday morning with a big coffee.
I'm about to do something very similar to my coupe, mine is Sapphire black and I'm okay with that but would much rather have that shade of blue.
Keep up the good work.

Glad you enjoyed it Do post some photos of your work, I love seeing before and afters!

[LemonConnoisseur]

Thank you.

No need to heat it up, just have a roller or a nice and flat trim tool to help you contour the sound deadening mats to the surface. One layer shouldn't really stop any of the trim and carpet from sitting in the right place.

I have several plans for my car, none of which are affordable to me at the moment. Being a powertrain design engineer, I'd love to 3D scan the engine bay and properly design an installation for a S65 swap, for example.

Cool, thanks Lucas.

That would be an epic swap, S65 I guess would be somewhat reminiscent to the Z8, or the Z4 GT3 cars.