RE: BMW M135i: PH Fleet

Tuesday 27th February

BMW M135i: PH Fleet

Project car complete, how does it stack up against BMW's own attempt?



The BMW M2 is a very good car. It's even better now that the slightly loose body control that afflicted earlier versions has more or less been eradicated for the latest model year. It's difficult to say what more you could want of a small, four-seat performance coupe, actually. It's fast, it looks great, it's fun to drive and the cabin is more than decent. And that's all very lovely, as long as you happen to have £46,700 to spend on a new car.

Last summer I took delivery of a five-year old BMW M135i. A three-door with a manual gearbox. It had covered a little under 30,000 miles and cost £17,500 (you can pick up leggier cars today from £14,000). Over the following eight months we modified it step-by-step to see if we could make a better car out of an already pretty good one. If you've been following the reports here you'll know the score. Working with Birds, the BMW specialist that's been tuning and servicing Bavaria's finest for longer than I've been alive, we've uprated the suspension, fitted a Quaife limited-slip differential and remapped the engine to liberate more power and torque.


Our reasons for doing so were pretty simple. The M135i was always a very likeable car but it was an imperfect one. It had a number of shortcomings that we reckoned we could put right. For me, its biggest issues were wayward body control on the kind of cresting, undulating roads you'll find draped across every moor and soggy hillside in the land, as well as the lack of a locking differential. The first shortcoming was unsettling and eroded your confidence. The second made the car frustrating and a little unpredictable.

What we never consciously set out to do was build an alternative to the M2. But with the project now complete and the total bill standing at £24,000, I couldn't resist the comparison. For close to half the price, have we built something that merits comparison with BMW's baby M-car? On looks alone, no we haven't. The M2 makes the M135i look weedy and undernourished. But on pure performance terms, yes we have. In fact, our M135i is actually quicker than a stock M2.


Before we look at that any closer, though, let me briefly run through the modifications we made to our Estoril Blue 1 Series. The first thing we upgraded was the suspension. Out went the standard BMW equipment in favour of Eibach springs and Bilstein dampers, built to Birds' own specifications. The new kit lowers the front end by 10mm, while a pair of spacers add a little width to the front track. The springs are 10 per cent stiffer than the standards items, while the dampers have less rebound damping.

Next, we fitted a Quaife LSD, added a short-shift kit and modified the clutch pedal to have a weightier action. Finally, with the car handling the way we wanted it to, we remapped the engine to 395hp and 420lb ft. The full B1 upgrade package, as Birds calls it, costs £6,643, which includes fitting, VAT and a two year warranty. You can check back through the previous reports if you're after a fuller description of each modification.

Incidentally, the upgrades can be made individually. They also fit the M235i coupe, too, as well as the later models, the M140i and the M240i. (You may remember we had decided to upgrade the brakes as well. Unfortunately, the supplier wasn't able to deliver the parts in time).


So, have we inadvertently built an M2 killer? Well, not exactly. With a 25hp and 51lb ft advantage over the M2 our car is faster in a straight line - enough that you can appreciate the difference from behind the wheel - although with less firepower to deploy to the road, and wider tyres with which to do it, the newer car does have better traction.

From there it's punch and counterpunch. The M135i has better damping pliancy over bumpy, uneven roads. You feel the suspension working hard to allow each wheel to rise and fall with the road and keep the tyres pressed firmly into the surface, which gives you huge amounts of confidence. By comparison the M2 skips along a little, although this particular car is better in that respect than any other M2 I've driven. The M2 has its much wider tracks, though, and you sense the car's greater poise and stability in every turn, and appreciate its more positive steering.


So the M135i doesn't humiliate the M2, but that was never our intention for it. The bare facts are this: you could build one to this exact specification for around £20,000, and for that money you'll have a car that's faster than an M2 and almost as much fun to drive. Although it'll never look anything like as purposeful.

During my 9,000 miles or so with the M135i it never missed a beat and hasn't cost a penny to run beyond normal servicing. Oh, apart from the £360 I had to spend to get a particularly nasty three-panel key mark repaired. It averaged a little over 30mpg, which isn't at all bad given the performance it's capable of. Regrets? Only one. I wish we had started with the much better looking, slightly more expensive M235i.


FACT SHEET
Car:
2012 BMW M135i
On fleet since: July 2017
Mileage: 38,650 (delivered on 29,800)
List price new: £29,995 in 2012. Bought for £17,500.
Last month at a glance: Tricked-up M135i holds its own against M2

Upgrades (all prices fitted, including VAT)
Bilstein suspension upgrade - £1,865
Quaife LSD - £2,033
Short-shift kit - £532
Clutch pedal modification - £113
Engine management upgrade - £2,700
Cost of full B1 kit - £6,643

Previous reports:
'You could get an M135i for that' - so we have!
Shockingly good improvement with new suspension fitted
Dan gets a dose of LSD and loves the effects
How far does power actually corrupt, then?

[Photos: Stan Papior]

Author
Discussion

si_xsi

Original Poster:

862 posts

125 months

Tuesday 27th February
quotequote all
For me, the main attraction of this package is not to have the same presence as an M2 but to have similar power and to do so under the radar, its the same ethos as my old 375bhp Supercharged Golf R32. But £2,700 for engine management upgrade rotate would be good to know the detail on what this actually includes, if its just a map, Birds are making a tidy profit! What checks are done to the engine on the second hand car before giving it more power? Impressed with the 2 year warranty though.

Edited by si_xsi on Tuesday 27th February 14:27

Notanotherturbo

280 posts

137 months

Tuesday 27th February
quotequote all
£6600 seems a lot for effectively an LSD, a remap and some suspension. Accepted they are good quality and well matched but you could buy high quality aftermarket parts for half that. Plus 1 series for me at least is the least attractive car BMW has ever made. Think I'd buy a 3 series with the same engine and add the some choice coil overs and a remap - and the good news is you can pretty much do that for just the price of the mods :0)

neil-1323bolts

507 posts

36 months

Tuesday 27th February
quotequote all
6600 wow there must be a lot better ways to spend that amount of cash , what a rip off

Jual Mass Flywheel

2,471 posts

85 months

Tuesday 27th February
quotequote all
I find it hard to swallow these prices. I just ahd a quickshift fitted t the Aero for less than £200. Even the garage commented on the quality of the work on the modified shift. As for the remap.............................

Warranty or not they're having peoples trousers down I'm afraid. Sure the cars good though.

GregK2

1,075 posts

76 months

Tuesday 27th February
quotequote all
Engine management upgrade - £2,700 yikes
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p1stonhead

14,953 posts

97 months

Tuesday 27th February
quotequote all
Having had a go in an M140i recently, its 110% going to be my next car. Loved it.

shoestring7

5,698 posts

176 months

Tuesday 27th February
quotequote all
neil-1323bolts said:
6600 wow there must be a lot better ways to spend that amount of cash , what a rip off
Well, I guess you could

a/ buy a random set of components on the internet and hope that when you bolt them on it makes the car better than BMW could manage/doesn't destroy/ruin your expensive N55/N58 engine (that's now not covered by the manufacturer's warranty)

or

b/ pay for a team of development engineers to work our a specification for suspension+remap that suit you/roads better that BMW's equipment. And have the kit made up to their specification.


SS7

si_xsi

Original Poster:

862 posts

125 months

Tuesday 27th February
quotequote all
shoestring7 said:
neil-1323bolts said:
6600 wow there must be a lot better ways to spend that amount of cash , what a rip off
Well, I guess you could

a/ buy a random set of components on the internet and hope that when you bolt them on it makes the car better than BMW could manage/doesn't destroy/ruin your expensive N55/N58 engine (that's now not covered by the manufacturer's warranty)

or

b/ pay for a team of development engineers to work our a specification for suspension+remap that suit you/roads better that BMW's equipment. And have the kit made up to their specification.


SS7
hehe Valid point and well made.

Silverbullet767

9,784 posts

136 months

Tuesday 27th February
quotequote all
A JB4 would've been a much cheaper alternative to the £2,700 engine management system upgrade. Easy to fit too.

Scottie - NW

780 posts

163 months

Tuesday 27th February
quotequote all
si_xsi said:
shoestring7 said:
neil-1323bolts said:
6600 wow there must be a lot better ways to spend that amount of cash , what a rip off
Well, I guess you could

a/ buy a random set of components on the internet and hope that when you bolt them on it makes the car better than BMW could manage/doesn't destroy/ruin your expensive N55/N58 engine (that's now not covered by the manufacturer's warranty)

or

b/ pay for a team of development engineers to work our a specification for suspension+remap that suit you/roads better that BMW's equipment. And have the kit made up to their specification.


SS7
hehe Valid point and well made.
That's not a valid point. If you go and buy a set of Bilstein dampers and Eibach springs their engineers have already worked on these components so they suit the car. I have used this combination on cars with great success.

As for the remap, most of these cars are out of warranty anyway and just because you pay £500 for a good remap somewhere else does not mean that has not had some good engineering time spent on it.

Birds charge the earth, and I'm not doubting it's good kit, it's just you can get the same with a little research and effort for an awful lot less.

British Beef

1,090 posts

95 months

Tuesday 27th February
quotequote all

I would take the M135 tuned. Fair enough it looks a bit sh!te, but its a compact hatchback, so function over form, I would be happy with that compromise.

As for the M2, I just dont like its proportions. Too much bodywork above Wheel Arches, and too high for its Width.

For a bit more Money the slightly bigger Alfa Guilia Quadrafolios just looks Perfect, for less than 6 month old similar price to M2.

fido

13,510 posts

185 months

Tuesday 27th February
quotequote all
Jeez, not this again. If you were selling a package - how much would you charge? Once you add in the components + labour + 2 year warranty - is there £1k leftover? And that goes towards fixed costs (R&D, garage, business rates etc.) I quite like the fact they don't do an M2 hatchback as it might attract the sort of knob-ends who drive Golf R's (that's not to say all Golf R drivers are k...s!)


Edited by fido on Tuesday 27th February 15:33

Ryvita

439 posts

140 months

Tuesday 27th February
quotequote all
"... added a short-shift kit and modified the clutch pedal to have a weightier action."

How, and more to the point, why would you want to make a clutch heavier? I can understand that if an uprated clutch (with uprated springs etc.) was put in to handle more power, that would lead to a heavier clutch pedal as a result but this sentence reads as if you've deliberately made it heavier as a desirable thing? Maybe I've just always had things with heavy clutches and not suffered the curse of a light clutch? confused

Birds is incredibly good at what they do, and their service is faultless and first class, but yes, by heck do you pay for it.

I was young, naïve and innocent once, and took a just-purchased E46 M3 to them for an inspection and service. The first proposed bill of works needed they came back with was 50% of the purchase price of the car.

Edited by Ryvita on Tuesday 27th February 15:40

ZX10R NIN

10,679 posts

55 months

Tuesday 27th February
quotequote all
Nice work PH yes it's expensive tuning always is, is it worth it? That'll depend on the type of person you are, for me it's worth it although I admit I'd get my ReMap done elsewhere,


SidewaysSi

4,272 posts

164 months

Tuesday 27th February
quotequote all
Ryvita said:
"... added a short-shift kit and modified the clutch pedal to have a weightier action."

How, and more to the point, why would you want to make a clutch heavier? I can understand that if an uprated clutch (with uprated springs etc.) was put in to handle more power, that would lead to a heavier clutch pedal as a result but this sentence reads as if you've deliberately made it heavier as a desirable thing? Maybe I've just always had things with heavy clutches and not suffered the curse of a light clutch? confused

Birds is incredibly good at what they do, and their service is faultless and first class, but yes, by heck do you pay for it.

I was young, naïve and innocent once, and took a just-purchased E46 M3 to them for an inspection and service. The first proposed bill of works needed they came back with was 50% of the purchase price of the car.

Edited by Ryvita on Tuesday 27th February 15:40
So you bought a dog?

5678

6,067 posts

157 months

Tuesday 27th February
quotequote all
Were retail prices paid for the work being reviewed here?

FN2TypeR

5,191 posts

23 months

Tuesday 27th February
quotequote all
article said:
Engine management upgrade - £2,700
Sorry, I still can't get over it rofl

Ryvita

439 posts

140 months

Tuesday 27th February
quotequote all
SidewaysSi said:
So you bought a dog?
Not really, they just wanted to do a lot of discretionary things that weren't strictly necessary to pass an MOT, like a small windscreen chip, paint correction, change part-worn but still legal tyres etc. Those items, on top of the major service (which I knew it needed and had factored into the purchase price) made a pretty gulp-worthy first bill. To be fair to them I had asked them what they thought it needed, it's just that they had higher (concours level) expectations than mine. smile

R8Steve

3,604 posts

105 months

Tuesday 27th February
quotequote all
FN2TypeR said:
article said:
Engine management upgrade - £2,700
Sorry, I still can't get over it rofl
Indeed! Mine cost under £500 and makes more power.

culpz

3,810 posts

42 months

Tuesday 27th February
quotequote all
Not wishing to partake or add comments to any further discussion of the total cost of the tuning and parts so far, i will agree with the end statement that opting for the '235i could have been a better bet. I know they're newer and more expensive, but i do think it's worth it alone for the aesthetic value.

Early M135i's are becoming a steal now but i just can't get on the the 1-Series looks at all. It's all subjective, i know, but i just think that the 2-Series shape just looks so right, especially when mated to that engine. It'd also have to be the ZF8 gearbox for me too. Would that restrict the power though?