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[Paul M]

This is sure to stir some heated debate

I'm toying with the idea of replacing the Omega with a 540i as my new commuting car. Don't get me wrong, the Omega is way cheaper to buy so it's maybe not a fair comparison, but after taking my 840Ci out today it reminded me just how gutless the Omega is. The gearbox is also much better on the 8, it's tighter and you can change it quicker, and the ratios are much better (being 6-speed helps) - the 540i will be the same, they come with much the same box although I think the ratios are slightly higher but it still pulls really well with the torque.

I've owned a 540i before, and it never missed a beat. Similar V8 engine to the 840Ci, which is far superior to the Omega V6 IMO. It's also much quiter on a cruise, I find the tyre noise quite loud in the Omega. It's also surprisingly easy to work on for a V8 for many jobs - you can change the plugs and coils in 20-30 minutes for example... heater valves can be done in 15 minutes, etc....

In my experience the 540i is a much better built car. Mine didn't have a spot of rust, none of the door check straps threatened to break off, the glovebox handle stayed attached, I didn't get misfires under load due to plug leads breaking down (there aren't any!), the idle was always 100% smooth. And that's on a car that was older and had higher mileage than my Omega!

Hmmmmmm... thoughts?

[TheBoy]

My brother had a 1998 540. Same age as my MV6 then. I personally thought it was gutless for the engine, but then like the Omega, is got a heavy car to pull.  Didn't rate the autobox much either (can't remember if it was the 6 speed one), or its gimicky sequential 'manual' mode.

Nice enough car, but it was £50k at the time (so double the cost of the MV6). He only had it a few months, so I'm guessing he didn't rate it that highly either.

Personally, I don't much like BMWs. Overated imho, poor dealers (as bad as Vx, but more expensive), silly reliability issues. I also do not like what the badge has become in the last 10 years (ie I'm a low-life double glazing sales rep, so I drive a 3 series) - the 318 has become the new 'yuppy' car, just as XR3i was in the 1980s.

But horses for courses - some people only consider BMW (ie people like my brother). It would be a boring life if we all liked the same things....

[Markjay]

A colleague of mine has been running a 535i Sport for a few years now, I get to ride in it often but find it less roomy than the Omega. The V8 is great though, if not the running costs. His mate is the top techie for the local BMW dealer, so services his car privately on the cheap, but otherwise it would have been prohibitive.

[Paul M]

Only the manual is a 6-speed. Slushy is a 5 I believe, and the crappy "manual mode" serves little purpose other than pub talk or so people can say it's a "semi-automatic" LMAO... no it's not, you pillock

As you've probably guessed by now   there's no way I'd swap the MV6 for a slushy 540i, so only the 6-speed manual is being considered. It's much more perky feeling, as the gearing is lower than the slushy, not to mention the lack of a torque converter meaning power goes to the road

I'm certainly not a BMW zealot, personally I think they produce one of the most vulgar cars on the road in the X5, and a lot of BMWs are driven by tossers. The 3 series in particular do have an image problem, although they are very good cars with a great chassis.

But, in my experience, the engine is way gutsier than the Omega's. The cars are similar weight, the 5 probably a bit heavier but it has more than enough of a power advantage to nullify that. But it's the torque spread where the huge difference lies, as much as I like a peaky engine for the back-road thrash I still enjoy a nice chunk of torque too for the more sedate stuff when I can't be bothered with the sound of the engine screaming in my ear (not to mention the petrol gauge plummeting). The V8 seems to manage this factor loads better than the Omega's V6.

[Paul M]

Oh and regarding servicing, personally I avoid main dealers regardless of the make, I've yet to be impressed with any of them.

I know a very good independent for BMW work about 30 miles from me, he's very knowledgeable, has been working on them for years, and is more than happy for you to stand around and watch him work on the car. Very reasonably priced too, so the dealers aren't an issue for me. Parts prices are a joke at times though, I'll give you that, but VX ain't much better - £180 for a set of plug leads FFS!?!

[TheBoy]

Strangely, I've found BMW parts to be often surprisingly inexpensive.

If your MV6 is lacking torque, are the multiram valves working properly. I'd be surprised if any V6 could manage the torque of a V8, but even so, it should have a reasonable pull from 1500rpm upwards...

[Paul M]

Try £500 each for the backboxes on an 840Ci, and the only non-BMW parts available are the "high performance" ones that are as expensive or sometimes even more so

Consumables like brake and service parts can usually be had at Euro Car Parts so are reasonably cheap.

Regarding the multiram, I wouldn't be surprised if it doesn't work properly, it's a Vauxhall after all. I should be pleased it still runs at all  

I will try and get it checked out some time, but time is of the essence and that engine is such a b1tch to do anything with.

[tunnie]

Paul M, I assume you have a pre-facelift omega?

Why not try a facelift, they made huge improvements with the facelifts in terms of cabin noise, ride & handling.

Try a facelift 3.2 MV6 Auto and see what you think, hell of a lot cheaper than the 540....

[Paul M]

Sorry mate, I'd rather walk

I have four limbs which I intend to make full use of, short of becoming an amputee (touch wood) I will not be buying any auto!

Besides, it's probably slower than my current MV6, as it's barely more powerful, yet has to waste half its power heating up transmission fluid

I do appreciate the facelift is reputed to be more refined, but I'm not sure I can get on with the interior, and it would also mean spending more money which again makes me consider whether I can get a "better" car for that money, even if it's older.

[tunnie]

Rather walk!!   Ok try the manual then.

Just found out that the V8 lump in BMW produces 286 bhp.... which does not seam a lot from such a large V8.

Considering the Swedish barges that the police use, which are the 5 cylinder 2.3's which produce 250 bhp...


I have driven a 3.0 MV6 Auto, which pulls and pulls from as low 1,500 rpm....

[Paul M]

Rather walk!!   Ok try the manual then.

Just found out that the V8 lump in BMW produces 286 bhp.... which does not seam a lot from such a large V8.

286 BHP is the "official" figure, they never bothered updating it from the original 4.0 V8, some certification crap I've heard. Look at the torque graph for the 4.4 V8 compared with that power figure, it doesn't add up  

Even better is the later (99 onwards) 4.4 V8, they introduced VANOS etc, torque jumped up across the range again but official power is still 286 BHP! If they were really keeping constant power they'd need to keep moving power and torque peaks further down the rev range, which didn't actually happen.

It's not designed as a proper high power engine, more a torquey, yet still quite powerful engine. The 4.0 V8 which came out in 1993 or thereabouts and actually does produce 286 BHP still has a slightly higher BHP/litre than the 3.0 V6 in the Omega, and way more torque. The high power version was of course the S62 5.0 V8 used in the E39 M5, 400 BHP.

Incidentally, that V8 can make a lot of power with the right setup. It's an all-alloy block with Alusil liners, has factory forged crank, sintered/forged rods and pistons... They've been supercharged to 450-500 BHP depending on who's rolling road you believe, without touching the internals. And the standard 6-speed box will take it no problem, well it handles the 600 BHP DINAN 8 twin turbo V12 no problem so a supercharged V8 is small fry .

[Paul M]

Considering the Swedish barges that the police use, which are the 5 cylinder 2.3's which produce 250 bhp...

Those 2.3s are turbo'd though... I had an Impreza WRX STi with a 2.0 turbo putting out over 300 BHP, and that was far from unusual in that car. Plenty of them around putting out lots more. 250 BHP isn't impressive from a 2.3 turbo; if you want a really impressive BHP/litre look no further than the Honda S2000's normally aspirated 2.0 litre putting out near 240 BHP! Comes at the expense of sod-all torque though, about 144 lb/ft I believe. For comparison both my 840Ci and my Impreza were over 300 lb/ft.

[TheBoy]

The 4.0 V8 which came out in 1993 or thereabouts and actually does produce 286 BHP still has a slightly higher BHP/litre than the 3.0 V6 in the Omega, and way more torque.

Both engines are of similar age, and produce near identical BHP/l. As I said earlier, a large V8 will always provide more torque, usually at the expensive of refined smoothness, hence why most exec cruisers stick to V6 config.

[Martin_1962]

Sorry mate, I'd rather walk

I have four limbs which I intend to make full use of, short of becoming an amputee (touch wood) I will not be buying any auto!

Two on the wheel one on throttle one on brake

[Paul M]

Both engines are of similar age, and produce near identical BHP/l. As I said earlier, a large V8 will always provide more torque, usually at the expensive of refined smoothness, hence why most exec cruisers stick to V6 config.

I disagree about this one, cross-plane V8s can be very smooth if correctly designed. It's a naturally balanced engine, as is an inline-6 and V12. The V6 is not a balanced engine, and ideally needs a balancer shaft in the vee to counter vibrations. That's one of the reasons companies like BMW, Jaguar and Lexus use inline 6s for their smaller engines, and V8 (or V12) for larger engines.

The drawback of cross-plane V8s is a lack of revvability due to rotating inertia from the counter balance weights on the crank. Hence you don't get high-revving cross plane V8s - the BMW V8 redlines at 6,700 RPM IIRC. On the other hand, flat-plane V8s which are used in high performance applications like Ferraris are very different - more like two inline-4s joined. These are not naturally balanced but can rev higher due to the lack of crank balance weights. You also don't get the characteristic V8 rumble from the exhaust - only cross-plane V8s do this.

V6s are generally only used for convenience of packaging IMO, it's easier to fit a V6 into most cars' engine bay than it is an inline-6. Especially FWD cars, it would be extremely difficult to fit the gearbox on the end of a transversely mounted I6! They're certainly better than I4s, but I'll take a V8 any day, lovely engines! Very tempted by the new Corvette LS7... 7 litre (yes seven!) V8, bet it sounds as well as it goes 8-) Clicky, although try and ignore the colour!

[Paul M]

Sorry mate, I'd rather walk

I have four limbs which I intend to make full use of, short of becoming an amputee (touch wood) I will not be buying any auto!

Two on the wheel one on throttle one on brake

Just like grandma told you  

One hand on the wheel, the other on the gearshift. One foot on the clutch, the ball of the other foot on the brake and the heel on the gas giving a little blip as you change down. Proper way to drive 8-)

[TheBoy]

I still think V8s have a certain 'harshness' to them, probably agrevated by the exhaust noise.

Now I'm not saying that is a bad thing of course....  

[Paul M]

You should try going for a spin in a standard 540i, super smooth and refined. You can barely hear the V8 exhaust note at all - personally I find it too quiet. Thankfully the 840 is a tad more raw and the exhausts free up the sound a little more (mine has standard exhausts).

I can't really compare with my Omega as it has a crappy aftermarket exhaust that sounds terrible, but I do find the V6 getting a bit harsh at the higher end of the rev range. The inline-6 fitted to my dad's 330 certainly feels loads smoother right to the red line.

I must admit, I drove a 3.0 Omega years ago that I quite liked the sound of, and my mate had a 2.5 V6 Vectra years before that, and it sounded nice (100% standard). However this one doesn't seem to have it, I'm not sure if it's because it actually sounds different, or because my interpretation is different. I hadn't owned a V8 at the time I heard the previous two, so maybe that's had an effect.