Modding the B3

[dodgyken]

First step taken today!

Dynamics gone in to be repaired and sprayed silver (instead of black)

The second step may offend some, the rear exhaust is being swapped out for a custom Daehler setup - absorption type instead of reflective. I have heard it on an M135 and it does give a fair dose of low end muscle.

The final step may be a remap to take her up to >380ps

Cheaper than buying a Jag anyway!!

[ali]

So that's why you didn't buy the V8 Discovery then!!
How will the PS increase affect fuel consumption on the B3?

[B10BRW]

The final step may be a remap to take her up to >380ps

Why not just buy a B3S, you get 400 bhp as standard

[dodgyken]

The final step may be a remap to take her up to >380ps

Why not just buy a B3S, you get 400 bhp as standard

If I opted for the B3S intercooler setup I would end up at 450ps.

indeed

(TBH I only want the sound!!_

[dodgyken]

Stage one complete

[MickB3]

Looking good! Silver wheels look 100% better than black. IMO

[dodgyken]

I liked the black when I first got the car - but by the end of last winter I was starting to really dislike the combination with the silver stripes. It didn't help having a lovely set of turbines for summer.

It looks a lot more balanced now - and as my daliances with more "special" cars has ended - IE not convinced they do they job any better than the Alpina - I will lavish some attention on it.

[dodgyken]

So yesterday was spent with the car (and unfortunately me for far too long) at Daehler.

The car was there for 3 things:
1) New exhaust
2) Remap
3) Warranty inspection

First up the exhaust:
There is nothing fundamentally wrong with the exhaust on the B3 - it is civilised at low revs and can deliver a reasonable howl at high revs. The problem is, for me, that is the wrong way round. I want a reasonable burble at low revs - a good growl at city speeds and then once on the motorway for it to be quiet. The suggestion was to swap the reflection exhaust for an absorption one. For this a Hartge one (with 4*83mm round tips) was suggested. In theory an easy fix - although technically not street legal in Switzerland.

In practice it was a little harder. The rear section was removed with 2 cuts about 10cm after the pipe kick out from the centre section. The Hartge one then had to have (for the battery side of the car) the silencer cut into and welded flat so it could be mounted using the original mounts. Next up the rear valence needed widening. I was a little horrified when I say this - BUT the kicked came when they told me what I was looking at was how Alpina had left it and not what they had done. (The exhaust surround Alpina used masked a very messy finish). Finally they cut another spare exhaust into the Hartge to create the perfect (straight) pipe to mount onto the original section. This was all then seam welded and sprayed to match the back boxes. The car was in from 0845 until 1915!!!

The result (although not yet driven in) is a far more bassy, solid sounding lower end. A burble is now apparent when idling in traffic - and the first couple of thousand rpm delivers a real buzz. Thick with bass and then building into a natural 6 pot sound. The sound of the turbos is now completely masked (a good thing in my book). This low end noise got me worried that motorway cruising would be a little boomy, how wrong I was, at 80mph the car is now quieter than it was before.

Second up the remap:
With 360ps and 500nm the B3 is hardly what you will call sluggish BUT the throttle response for motorway "pulls" (60-75mph) can be a little heavy and despite the numbers it can shuffle down the gears a little quickly if you give it a poke at low revs.

Pulling out from the garage I had the car in manual mode, simply because I was more looking to find out how the exhaust sounded than how the map performed. The first decent prod of the throttle revealed that the car still accelerated rather quickly. Daehler himself reckoned it was going to be around the mid 390s. (Originally he reckons on around 365-370ps - having tested a few - and that remapped (inc air filter) they deliver between 390-407ps)

360 to 390 (give or take) is not going to jump out - especially given a similar jump in torque - and only when I poked it again a little later, holding a high gear, did it feel any quicker. It was only when, about 50 miles later, after I had come off the 80mph cruise (and then back onto it) did I begin to feel the extra torque. Switching the OBD to instant revealed that the fuel economy was noticably better - hovering around 0.5-1l/100km LESS than it did before.

Only once I was back off the motorway did I knock the gear lever back into D - and in doing so finally feel he real merits of the map. The extra torque causing the gearbox to shuffle up the cogs faster than ever - 5th gear engaged at 50kmh and it holding it under throttle pressure (not full but a lot more than before).

Thirdly:
The 2 year BMW warranty expired at the end of last month - and I hadn't done anything about extending it - but for £320 I was offered a full 1 year warranty - and was quick to take the option!!

The bill was suitably Swiss in size but a lot cheaper than upgrading to either a B3S or the more exotic alternatives I had been looking at - and the results so far are pleasing. The car now sounds more "me", which quite frankly was the only area in which it let me down before. The interior, ride/handling and performance/economy were never really an issue - and having solved this area of the cars character I am looking forward to another couple of years of ownership.

[MickB3]

Brilliant write up ENJOY.

[B10BRW]

The 2 year BMW warranty expired at the end of last month - and I hadn't done anything about extending it - but for £320 I was offered a full 1 year warranty - and was quick to take the option!!

Where did you get your warranty from , BMW in the UK want over £800

[dodgyken]

The 2 year BMW warranty expired at the end of last month - and I hadn't done anything about extending it - but for £320 I was offered a full 1 year warranty - and was quick to take the option!!

Where did you get your warranty from , BMW in the UK want over £800

Not sure - I would have to check the paperwork.

2 year warranty of the Discovery I just bought was 1000chf (reduced from 1400chf) - £650 instead of £900!

Warranty prices are a little cheaper over here.

The Disco is currently off the road as the dealer is replacing the headunit (due to broken buttons). A zero cost fix for me!

[dodgyken]

Update on the remap:

Clocked almost 300km over the weekend with a trip to Davos. In the past the computer would have read around 10l/100km - and the needle down to halfway. This time - 8.4l/100km on the computer - and the needle at 5/8th.

The exhaust at start up at -5c sounds mental.

[Peter&Janet]

Great write up Ken.
Pleased your enjoying the extra performance + fuel consumption.

Although i don't had the beast any longer it's still very interesting and couple of thoughts. Do you have a graph of the map and I assume it's generic where UK companies can do similar, Oh & did the insurance get hit with the upgrade?

There's two B3 for less than 18K at the moment and these cars are going to be absolute bargains in a year or two, very tempting.

[dodgyken]

Great write up Ken.
Pleased your enjoying the extra performance + fuel consumption.

Although i don't had the beast any longer it's still very interesting and couple of thoughts. Do you have a graph of the map and I assume it's generic where UK companies can do similar, Oh & did the insurance get hit with the upgrade?

There's two B3 for less than 18K at the moment and these cars are going to be absolute bargains in a year or two, very tempting.

Answers:
No graph - as it wasn't tested before and after. I am not that fussed about the actual numbers - the car is hardly slow in standard form. What I care about is how the car feels - the revs rise far quicker than they used to - and the shifts on partial throttle happen at far lower speeds. That to me suggests some pretty decent numbers.

Insurance isn't an issue as along as the performance is "low" it doesn't need to be declared. The exhaust was issued with a Swiss conformity certificate so doesn't need to be mentioned!

I am happy with the results of all the work.