I've just read HJ's latest report on the Audi R8.
Having just been "done" for speeding (47 in a 40 limit) in SWMBO's 1.6 Focus, I can't help feeling that the power of the R8 (as an example) is a little unnecessary ;-)
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To me, a car is underpowered if it has less than around 100bhp/tonne. If I wish to join a fast moving carriageway, or perform an overtake on an A Road, I want my car to be able to get up to the required speed more or less as quickly as possible. 30-70 in 6-8 seconds is about right. Much more than that, and the car is in my opinion underpowered.
When overtaking, you want to mimimise the time you spend on the opposite side of the carriageway. In a Focus 1.6, this is not really that easy.
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Oh dear I feel my age:-)
When I grew up and started driving, the bog standard Cortina/1100 could not achieve 100mph.. Most cars had a cruising speed if lucky of 65-70mph.
By today's standard underpowered (0-60 in around 16 to 20 deconds)... but perfectly driveable then and now.
How often can you use 0 to 60 in 7 seconds on UK roads? Not often...imo.
Having driven a deisel 1.4 Peugeot 106 on and off for over a decade - the slowest car in UK when launched with 0-60 in some 19 seconds- I have to say for town driving and almost all motorway driving you only notice the lack of power - when loaded with 4 adults or going up a long incline. If both combine, I admit it's pitifully slow:-(
So I say underpowered is 0 to 60 over 18seconds. For all intents and purposes, you cannot use the extra power on a daily driving basis. (weekends and pleasure driving excepted).
(I drove a 1967 Lotus Elan S3 with 130hp (much modified) for 2 years as a fun car. 0-60 around .5 secs.. Great fun but unuseable except of clear country roads.. )
madf
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Normal driving does not involve many 0-60s - it's far more often about acceleration from between 30 and 50, and thus 30-50 and 50-70 figures are what matters. Most diesel TDs are not that sharp 0-60, but some are very flexible in the mid-range acceleration stakes. That's what matters to me, at least.
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As others have implied, there's a big element of user perception and expectation in this. Mrs Beest grumbles that her 68 bhp Fabia is slow - which it is, but it's reasonably relaxing to drive (and very easy in town because what torque it has is well spread) if you accept that you won't overtake anything quicker than a tractor on a single carriageway. Incidentally, I drove a 115 bhp 2.0 Fabia once, and the engine seemed entirely inappropriate to the car.
On the other hand, my Ransomes Ajax lawnmower probably is underpowered, because Mrs B can't move it at all. (Although if I had a proper Mk 2 and not a modern-trash 1968 Mk 5, that might be different, eh Cardew?)
}:---)
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I used to have a Mk3 Golf 1.8 CL, (75bhp, notable weight increase from the Mk2 Golf).
It was satisfactory for driving round town but on motorways it was inadequate. At motorway speeds the acceleration was glacial so overtakes often had to be planned well in advance and occasionally had to be aborted as a quicker car did a proper job of it.
There is a long quite steep uphill stretch of dual carriageway near where I used to live, and from an indicated 75mph the Golf would not maintain its speed and actually decelerate up the hill, regardless of driver input, that to me defined underpowered.
My first car was a Mk2 Cavalier 1.8i (115bhp) so thats my rough benchmark for satisfactory performance, anything quicker is desirable, anything slower is not for me. The Golf was a bit of a mistake.
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If you have to really think hard and plan to the extreme before attempting an overtake the car is underpowered. The Aygo is great round town - as quick as most vehicles from 0-30 mph and it will cruise happily at motorway speeds, but when motorways are busy and an overtake is required (wagons on inclines) you need to plan to pull out well before you start to lose speed due to the incline.
The ability to see a gap and go knowing you have plenty in reserve is so much more relaxing. The car doesn't need hundreds of bhp though, the A2 TDi 75PS I had would pull with no fuss from 60 in top and soon get to illegal speeds.
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Define underpowered
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>
a vehicle that you make to go faster by pushing your back in and out as you drive
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a vehicle that you make to go faster by pushing your back in and out as you drive
Lol !
;oP
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I've just read HJ's latest report on the Audi R8. Having just been "done" for speeding (47 in a 40 limit) in SWMBO's 1.6 Focus I can't help feeling that the power of the R8 (as an example) is a little unnecessary ;-)
You could doubtless have performed the same law breaking activity in a 2CV.
It's power to weight that matters, and in this regard MichaelR has similar views to myself.
110bhp per tonne is my personal cutoff point, with 130 bhp per tonne being more ideal.
Before I opted out of the company car scheme, higher up the order was getting the most bhp per kilo in my allowance bracket along with a minimum of five cylinders, than going for a "badge". The result was that I tended to have creamy V6s with 170-200BHP and 110-135bhp/tonne. Now opted out and with free rein to choose what I want, my current V70 has about 160bhp per tonne from a rough calculation and is the first car that I've owned which even fully laden never feels in the remotest sense to be underpowered.
It's riding sportsbikes that has redefined my understanding of power to weight though. Mine has about 400bhp per tonne laden with me on board, and the ability to change speed on demand in an effortless blink never gets boring. Used sensibly, it opens up a world of opportunities. My bike is overshaddowed though by the likes of a friend's with about 550bhp per tonne (again laden with him aboard), which in turn is overshaddowed by new GSXR1000s, R1s, 'Blades, and so on; in the never ending quest for higher bhp (160-170 is fairly normal) and lower weight these bikes are approaching 700bhp per tonne laden. Frankly though, we have now exceeded what to me at least is considered adequate of a laden bike for road use (400-500bhp per tonne); if I put 110bhp per tonne before other qualities in a car, then I put other qualities before 700bhp per tonne laden in a bike.
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As others have said what?s underpowered is largely a function of where you?re driving and what you asking the car to do, so it?s primarily a subjective matter. There are clearly some vehicles which are just too heavy for the engine to perform the majority of duties and IME this tends to be 1.6 or 1.8 petrol engines in mid-range saloons or 1.4 petrol engines in a Ford Focus size of vehicle where any acceleration, even when unladen, is dangerously slow or so raucous as to be unbearable to live with.
That aside I can?t see that the use of equations such as tonne/bhp are useful in determining what is or isn?t a general underpowered vehicle. Unless I?m misunderstanding the equation, which is entirely possible, using the 100bhp/tonne as a general threshold of what is underpowered seems iffy. The 130bhp Mondeo 2.0tdci Ghia weighs 1587kg and produces 130bhp, the 130bhp MAX 2.0tdci Titanium weighs 1897kg, the Audi A4tdi produces 140bhp and weighs 1430bhp, the A6 with the same engine 1525kg (similar bhp/weight ratio as the old audi 100 mentioned .in the OP) All of these vehicles are under 100bhp/tonne yet for general use none of them are remotely underpowered. If one uses 130bhp/tonne as a yardstick then V6 Jaguars, Audi and BMWs are rated as underpowered, which TBH for the vast majority of people and uses they clearly are not.
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When a car is actually developing 100 bhp/tonne it will fly. The problem is actually having anything like that on tap because these are maximum power outputs, not what it s to be expected in day-to-day cruising.
So if the car can get up to, say, 80 bhp/tonne for a few seconds before the engine expires, it'll be underpowered. If, on the other hand, it's producing 70bhp/tonne from 2,000 revs like the big diesels named above, it's plenty quick enough.
Looking at this my BMW 5 Series puts out about 112bhp/tonne. On song, it's plenty quick enough; however at 1,500 revs in fourth, with the petrol engine and the long accelerator travel, my 306 turbo diesel would leave it for dead until about 60 mph by which time the BMW would be catching up and would eventually get ahead.
The answer is not to drive like a granny in the right conditions of course, but if you want effortless performance all the time, a diesel (or a really big petrol engine) is the way to go.
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if i'm on an 'A' road, following someone doing 45-50mph and i want to do an overtake at a shortish straight, that is safe........ i.e out and back with no chance of a drama.....then a car that does this is acceptable.......one that doesn't is underpowered
my car.....V6 3.0 auto Jag is fine............wife's car.....2.0 manual turbo diesel Jag estate is acceptable, but only just (if it wasn't for the economy it would slip into being a no-no i suspect.....will try the 2.2 model as or when we can afford it)
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Of course, on the other coin we have to define overpowered......
1. Leaves tyres behind when pulling away from a standstill.
2. Excessive torque steer.
3. Scares passenger
and especially......
4. Scares driver!
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you forgot the tyres spinning on the rims like cathrine wheels MB3
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Most run-of-the-mill cars are underpowered by Westpig's definition, although they would have been regarded as very fast when I was young.
So let's have a proper definition of underpowered.
An underpowered car is one that won't haul itself up a 1-in4 or 1-in-3 slope in any forward gear with all its passenger seats occupied (reverse used to be the lowest gear on most cars. First gear is fine, but if you have to reverse up the hill the car is underpowered).
Austin 7 Ruby with poor comnpression, anyone?
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> Austin 7 Ruby with poor comnpression, anyone?
Yes well 28 horsepower could be turned over on the starting handle
You try that with 20:1 compression.
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TourVanMan TM < Ex RF >
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28 hp? You exaggerate TVM. And what have starting handles got to do with it?
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The ring gear went on my fathers 7 tourer. Hence the electric starter wouldnt. so it was starting handle.
and yes 8 horses was nearer the mark.
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TourVanMan TM < Ex RF >
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