BMW's and torque?

been messing on google and i can't find bugger all for figures on torque the different engines make! it's ok saying it has 170, 180 and 193 bhp but i can't find the torque figures. both the 2.5 and 2.8 are 193bhp or abouts i think but surely the 2.8 develops more torque? no point in having 190bhp and only being 100nm torque is there!

Reply to
Vamp
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Its not the amount of torque that matters. Its the shape of the torque curve x rpm. And 10nm of torque would be great at 1,000,000rpm...

Remember that half the torque at twice the rpm = same acceleration at the same road speed due to it needing half the gearing?

Reply to
Burgerman

formatting link

170bhp / 180lb/ft 193bhp / 207lb/ft
Reply to
Grant

Did you check my Datasheet?

Reply to
DervMan

nope :)

Reply to
Vamp
2.8 makes peak power (142kw/193 hp) @ 5300 rpm 2.5 makes peak power 125kw/170 hp @ 5500 rpm

not a great difference but its there :)

figures being for a 328 and a 323 late model E36's

although the earlier 325i as up to about 97 is listed as 192 hp 1hp from

300cc :)
Reply to
Rob
[...]

The 4.0 M60 and the 4.4 M62 which replaced it both make 286bhp.

...however:

M60 4.0l 286bhp @ 5800, 295lb ft @ 5100

M62 4.4l 286bhp @ 5700, 310lb ft @ 3900

The M60 is a rev monster, the M62 a stump puller - very different to drive, the M60 seems more exciting but the M62 is just plain faster...

A
Reply to
Alistair J Murray

There is an old saying "Torque wins races and horsepower sells cars."

Fraser

Reply to
Fraser Johnston
[...]

It's the area under the curve that counts. :)

I went from the 4.0 M60 in an E38 to the ALPINA 4.6 version of the M62 with 340bhp @ 5700 and 350lb ft @ 3700 and a couple or regular passengers with good ears wondered if my new gearbox was less keen to downshift...

A
Reply to
Alistair J Murray

Don't know where that came from. The only reason Diesels do well in 24h races is that they don't have to stop every 100 miles or so for fuel.

Reply to
Tim S Kemp

Old it may be, but I'm not entirely sure it has much relevance, these days.

If you look at F1 or Champ cars, there's not much overtaking done driving out of corners. It's normally something like slipstreaming, or towards the end of a straight - and this is where peak power matters, or on the brakes from a long straight going into a fairly low speed corner.

The only time where torque truly seems to matter to top level racing, is off the start line, or perhaps getting the drive out of a corner to allow a closer attempt at the end of a straight.

In F1 it's _always_ the engines that produce the most peak power, that tend to do the best at the power circuits - and in general, really, assuming they have a competitive aero package. The engines reputed to produce good torque may be good off the line, or get good drive out of corners, but doesn't normally make the _engine_ dominate the race.

At top level racing, it's peak power that matters most - because that tends to be where the engines are, or are heading.

Reply to
Douglas Hall

Yes, but with more easily accessible torque, and still enough power relative to the roads driven on, plus the fuel benefits, it's not at all inconceivable that they could win.

But torque doesn't win races. Horsepower does. It's the power at the end of the day that determines how fast it can go. The torque gets it to its top speed, the power keeps it there. At the top end, power is king.

Reply to
AstraVanMan

They're really the same thing. BHP is derived from torque and revs. So with a 'flat' torque curve the higher the engine can maintain it, the more power.

Reply to
Dave Plowman (News)

Oh yeah, I know that, but the fact still remains that if one car develops more peak power than another, all other factors being equal, it'll be able to hold a higher top speed. Ok, one car's peak power might be at around

4000rpm (a TD for example) and another's might be at 6500rpm or higher, meaning that the diesel's power is more usable, requiring less neck-wringing to actually get to the power, but at the end of the day, if there's more there, there's more there. Period.

A while back I was doing a bit of google-digging on the 4 litre twin-turbo diesel BMW put in the E38 7-series, and the general consensus was that it was fantastic up to around 100mph, but much after that and it was blown away by the larger petrol engines.

Reply to
AstraVanMan

Torque ALWAYS matters. But what you really mean is that its better to have more torque (which is more power) at a lower rpm as well as at high rpm. Its the shape of the curve that matters. And the L E N G T H of the high bit of the torque curve. This is where diesels fall down because they have very short useful rpm bands. Meaning short gearing and more gear changing needed.

Reply to
Burgerman

Look up the new 2litre diesel 3series based Alpina, only 200bhp but over 400 pound torque!! and apparently it quite enjoys a good revving

Reply to
Ken

Didn't a BMW 2litre D get the overall win at the 24hr Nurgbergring (or however you spell it) in '98?

Reply to
Ken

It's a drag racing expression.

Fraser

Reply to
Fraser Johnston

I meant this in the context of the quote, though - referring to racing. I do wonder if the original quote is referring to road racing?

But anyways, it's not the (reputedly) more torquey engines that tend to do well in, say, F1 (apart from around some of the twisty, Mickey Mouse tracks ;-)), ultimately it's the ones that produce the most peak power. Because the ones that do produce better torque curves, don't get the same opportuinity (as say you would driving on the road) to exploit that and enable them to race better.

Sure they may get better drive _out_ of a corner - but it's rare that really helps in F1 to win places - unless it just so happens to help get a better overtaking possibility at the end of the following straight - but ultimately the car achieving the best peak power (assuming similarities in gear ratio) that will tend to win out at the end of the straight (assuming similarities in terms of downforce and drag).

I just don't think the quote mentioned, stands up to high level motorsport - F1 and Champ cars are all about peak power to be competitive. The circuits where other engine characteristics may come into place are few and far between, and even then the differences are most likely quite subtle and more likely down to aero or tyres.

The Renault engine in F1 is reputedly best from an area-under-the-graph perspective. And this is observable seeing how they get off the line, and how they drive out of corners. But that only tends to help them gain places at the start, and be able to defend their positions. They need to flatten their wings and up their limiter to be able to compete at the end of straights - and lets be honest, that's where all the (non pit related ;-)) passing tends to take place.

Certainly for F1, the _engines_ that tend to dominate are the ones that produce the most peak power, and don't lunch themselves at every opportuinity.

Totally different scenario, though, for driving on the road.

Reply to
Douglas Hall

Ah, makes sense for that scenario.

As in F1 - getting cars off the line.

But for racing in F1, they never seem to be much emphasis on torque, all the interest is on peak power. Because the opportunities to exploit better torque curves don't really happen in F1 (apart from the start of the race).

Reply to
Douglas Hall

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