Atacama Yellow 35is build thread

[Busterboo]

The yellow and grey go together very well, don't they? The seats look superb and the wood trim adds depth to the interior. (Presumably, body colour mirror backs were standard on both orange and yellow, unlike the usual silver.)

A very attractive car in many ways. Now, just make sure you have BMW Insured Warranty.

[My replies are in square brackets below, B21 ... ]
Hello, yes I like the interior, each to their owm, I do have a carbon fibre interior to fit courtesy of Silverstar..you are making me ponder..
[The wood makes the interior deeper, the carbon fibre shallower. However, 'different strokes', of course.
The 35is in AY and VO as you say had colour matched wing mirrors.
[If I were you, I'd put silver on. Tell the world what you've got.]
I looked at the warranty but decided that I’d embrace the ‘opportunities’ created by decaying parts…
[Please remember that those "opportunities" can be very expensive. And they will happen.]
I wanted to tweak the engine which I think would invalidate any warranty?
[If 340 bhp & 500 Nm in over-boost aren't enough for you, should you perhaps be looking for another car?]
So I’m getting rid of the adaptive suspension and I have a set of Index 12 injectors waiting in customs.
[Is spending money to lose a feature a brave move unless you're certain your alternative will be right?]
I think by 2011 the HPFP was addressed but for £750 I’ll cover it if / when it happens..
[Mine's covered for a lot less than £750.]
Whatever, you have a beautiful car.

[B21]

The premade "OTS" maps with MHD are pretty good for what they are. They are quite close to maxing out the stock turbochargers so you don't get much extra performance from a custom tune but there's quite a lot of room for improvement when it comes to partial throttle performance and controllability. Also I've seen the OTS maps don't work great with the DCT, the shifts trigger elongated torque limits from the DCT.

With xHP you want to be using the Stage 2 maps. The stage 3 ones are a little aggressive in their downshifting behaviour, some people like that but it doesn't make the shifts any faster, just more jerky.
xHP have given me an account so that I can provide custom xHP tunes, I think you just need to have purchased a flasher license first but don't need to but the map packs.

Great all noted

When the turbos go south I’ll give you a call…

I gather an issue is for UK cars the steering gear limits options on turbos and other paraphernalia?

Plus there is a break point on stock diameter turbos vs larger bores..feeding through to the FMIC etc?

[B21]

Buster boo..

All noted..all I can say in my defence is that I pondered all these things many times over 4 years..I accept full responsibility for my decisions and actions

[R.E92]

The premade "OTS" maps with MHD are pretty good for what they are. They are quite close to maxing out the stock turbochargers so you don't get much extra performance from a custom tune but there's quite a lot of room for improvement when it comes to partial throttle performance and controllability. Also I've seen the OTS maps don't work great with the DCT, the shifts trigger elongated torque limits from the DCT.

With xHP you want to be using the Stage 2 maps. The stage 3 ones are a little aggressive in their downshifting behaviour, some people like that but it doesn't make the shifts any faster, just more jerky.
xHP have given me an account so that I can provide custom xHP tunes, I think you just need to have purchased a flasher license first but don't need to but the map packs.

Great all noted

When the turbos go south I’ll give you a call…

I gather an issue is for UK cars the steering gear limits options on turbos and other paraphernalia?

Plus there is a break point on stock diameter turbos vs larger bores..feeding through to the FMIC etc?

Steering column goes right next to the turbos, it means that most turbo kits don't fit right-hand Z4s because the outlets from the turbo foul against the steering column.
There are options but they aren't as nice as I'd like.

You can get turbo upgrades that will work on the stock outlets, they will be stock housings with upgraded internals. Will be capable of flowing less air than the larger options but still an upgrade over the stock ones.

You should consider some wider wheels if you want to improve grip. The standard wheel widths don't allow for much rubber, I was really struggling for traction on the standard 255 width rears. I have 275 Michelin PS4S on my 437M wheels and they grip really well, even in damp cool weather.

[tiglon]

The premade "OTS" maps with MHD are pretty good for what they are. They are quite close to maxing out the stock turbochargers so you don't get much extra performance from a custom tune but there's quite a lot of room for improvement when it comes to partial throttle performance and controllability. Also I've seen the OTS maps don't work great with the DCT, the shifts trigger elongated torque limits from the DCT.

With xHP you want to be using the Stage 2 maps. The stage 3 ones are a little aggressive in their downshifting behaviour, some people like that but it doesn't make the shifts any faster, just more jerky.
xHP have given me an account so that I can provide custom xHP tunes, I think you just need to have purchased a flasher license first but don't need to but the map packs.

Great all noted

When the turbos go south I’ll give you a call…

I gather an issue is for UK cars the steering gear limits options on turbos and other paraphernalia?

Plus there is a break point on stock diameter turbos vs larger bores..feeding through to the FMIC etc?

Steering column goes right next to the turbos, it means that most turbo kits don't fit right-hand Z4s because the outlets from the turbo foul against the steering column.
There are options but they aren't as nice as I'd like.

You can get turbo upgrades that will work on the stock outlets, they will be stock housings with upgraded internals. Will be capable of flowing less air than the larger options but still an upgrade over the stock ones.

You should consider some wider wheels if you want to improve grip. The standard wheel widths don't allow for much rubber, I was really struggling for traction on the standard 255 width rears. I have 275 Michelin PS4S on my 437M wheels and they grip really well, even in damp cool weather.

I'm curious, did the 275 rears fit OK or did you have to make modifications?

[R.E92]

I'm curious, did the 275 rears fit OK or did you have to make modifications?

With those wheels they fit fine without any mods.

[B21]

I'm curious, did the 275 rears fit OK or did you have to make modifications?

With those wheels they fit fine without any mods.

Strange…for me my Zito 935 with 265/35 18 rears (235/40 18 front) on my 20i ran no issues with 10mm spacers to bring them close to OE offset

On the 35is the same set up was grinding the right hand rear wheel arch away..

Even with a 5mm spacer it still occasionally touches.

That in part could be caused by the woeful rear adaptive suspension…too soft and way under damped ..

[R.E92]

I'm curious, did the 275 rears fit OK or did you have to make modifications?

With those wheels they fit fine without any mods.

Strange…for me my Zito 935 with 265/35 18 rears (235/40 18 front) on my 20i ran no issues with 10mm spacers to bring them close to OE offset

On the 35is the same set up was grinding the right hand rear wheel arch away..

Even with a 5mm spacer it still occasionally touches.

That in part could be caused by the woeful rear adaptive suspension…too soft and way under damped ..

No issues here and I have adaptive suspension. The wheel offsets will probably be different on the Zitos.

[tiglon]

Thank you R.E92.

B21, I've had a look at those Zito's - the offset for the 9.5j which I assume you have on the rear is either 35 or 45, the 437m's rears are 10j and ET40.

[B21]

Thank you R.E92.

B21, I've had a look at those Zito's - the offset for the 9.5j which I assume you have on the rear is either 35 or 45, the 437m's rears are 10j and ET40.

Hello yes at rear offset of 35mm the 265 was catching on bumps all the time, with 40mm offset just very occasionally (maybe cause the liner is now worn away), thats just on the RHS.

When I fit the LSD and rear bushes etc I'll get the steering geometry checked..all that may bring it into line..

[R.E92]

The 437M are 10J rear so that will also play a part, my tyres are 275/30r19.

Previously I had some VMR V710 wheels, they were 9.5J ET33 with the same size tyres and they rubbed the wheel liner under compression. They were a good lesson in the importance of quality wheels in the correct offsets, aside from the rubbing they buckled in multiple places and also were really heavy and completely ruined the way the car drove.

I don't think you'd want the weight of a cast 10j rear wheel if you care for the dynamics of a vehicle.

[B21]

The 437M are 10J rear so that will also play a part, my tyres are 275/30r19.

Previously I had some VMR V710 wheels, they were 9.5J ET33 with the same size tyres and they rubbed the wheel liner under compression. They were a good lesson in the importance of quality wheels in the correct offsets, aside from the rubbing they buckled in multiple places and also were really heavy and completely ruined the way the car drove.

I don't think you'd want the weight of a cast 10j rear wheel if you care for the dynamics of a vehicle.

Good to know thnx

[Nanu]

Looking forward to monitoring the upgrades

[B21]

Looking forward to monitoring the upgrades

Starting Monday 18th October there is a fairly intensive 3 car swap over of bits and changes..I’ll write up the plan next week and take a few pictures of the goodies

[B21]

The Prologue

Part II (Long)

I explained the history of how I ended up buying a AY 35is and my initial disappointment with my choice.

To explain / justify this we need to look at it from the perspective of someone who has tweaked and tuned without regard to cost over a 4 year period a 20i MSport Auto, and of course a question of bias.

So it’s my view and I appreciate others may disagree but it’s based on over 2,000 miles of use of the 35is and looking at the differences, not to mention 30,000 miles in the 20i.

It’s rare to be able to jump from one car to another side and compare them!

Comfort

The ride on the 18" runflats on anything but smooth surfaces are poor, especially small ripples in tarmac.

The adaptive dampers were too softly sprung but too harsh compression damping, then not enough rebound damping, toggling the sports mode did little to improve matters, just worsening the compression damping that was already too stiff.

The multiway electrical adjustable seats were great..over a long run being able to easily move them around kept the driver comfortable.

Handling

Definitely the most negative aspect, the combination of the run flats and adaptive suspension was very disappointing, far worse than the 20i, I would estimate that the 20i could run 10-15mph faster on any road with bends than the 35is.

Tramlining was bad although with an average of 3-4mm on the tyres that didn't help.

I didn't find roll too bad actually despite only having the same ARBs as the stock other E89s.

Pitch and weight transfer were much more noticeable, causing braking and turning to be an unpleasant affair.

The extra weight on the nose made sudden changes in direction much slower than the 20i.

In contrast sat on a motorway or high speed dual carriageway the package gels and as an autobahn burner its great..just not what I signed up for.

Engine

Compared to the highly tweaked 20i overtaking at say 50-60 was disappointing, again, despite the DCT box running lower gearing so spinning the engine faster at any point. Seems like the low back pressure and much fettled bigger twin turbo on the 20i scored well.
I would say that the 35is needs another 200-300 yards to safely execute the same manoeuvre as the 20i.

In contrast, once the peddle had been pressed for a period of time then the surge of power was relentless and highly impressive, if it was not for the worry of what to do about the upcoming corner.
Gearbox
The DCT box in its day must have seemed splendid, however next the ZF 8HP it’s just not quite as good. It doesn’t pick a gear for the occasion quite as well as the 8HP. Stop start and slow speed crawling again highlight the limitations. Although the gear changes are fast, to me, they are no better, and not as smooth as the 8HP.

Sound
There is no doubt that the noise of the 35is with its gutted back box (or whatever they do to change the Db level) males on full chat is splendid. However it becomes an irritating drone on a steady throttle in the 60-70 area.

Sound system
The car came with the 677 Top-Fi 14 speaker DSP system. Again, maybe compared to the 676 Hi-FI 11 speaker system I had in the 20i as standard then it might have sounded better. However compared to the Audiotec Fischer Match 7 DSP/amp plus Eton/Audison/Rockford Fosgate speakers it came across as dull, blurry but loud..a bit like the rest of the car.

Seats
The multiway electric seats are great; being able to easily tweak them, just a bit, on a long journey enhances the comfort of the trip. Pity the lumbar part was still missing off what was a fairly fully loaded car.

Cosmetics
The car was in great condition, clearly spent a lot of time in a nice dry garage and little high speed use judging by the lack of stone chips. The old 3 screw rear lights were still in good condition.

The old pre LCI side repeaters really showed their age, cheapening the car somewhat.

The bumper, rear valance and diffuser colour sequence, like all 35i versions, optically makes the bottom look like its prolapsed. .IMHO yellow, yellow black doesn’t look as good as yellow, black, yellow.

The silver grills on the front and the silver line across the lower area along with the silve headrest covers arr personal choice but in my case are going.

The heated steering wheel was a novelty, but having tried it I much prefer a Royal steering wheel and turn up the cabin heat. It again IMHO showed the cabin's age.

Interestingly, I assume because its not been in the sun as much, the Atacama yellow is slightly lighter than the newer 20i which has spent almost all its life outdoors.

So, this is the end of the whining and carping. If you are still reading this you can probably deduce I was underwhelmed and pondered for over 3 weeks whether to return the car.

However, as others pointed out I was comparing a 10 year old car in original condition at 50,000 miles against a highly refined and adapted car reflecting my personal tastes.

So I crossed the Rubicon and now we move on!