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This is the Forum for all your Citroen Technical Questions, Problems or Advice.

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tomsheppard
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Post by tomsheppard » 04 Sep 2005, 00:50

If it had torque, it wouldn't need six speeds.

Sl4yer
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Post by Sl4yer » 04 Sep 2005, 01:13

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tomsheppard</i>

If it had torque, it wouldn't need six speeds.
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I don't understand your point Tom. It doesn't actually NEED 6 gears, but the sixth is there for cruising and economy. As I said above, its effectively an overdrive. It probably reaches its maximum speed in 5th. There aren't actually many occasions when I use 5th anyway (normally only when joining a motorway between lorries, or driving through 40mph limits at roadworks).
I remember when cars only had 4 gears - now at least 5 is standard. Is that because modern cars don't have enough torque?

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Kowalski
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Post by Kowalski » 04 Sep 2005, 01:41

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tomsheppard</i>

If it had torque, it wouldn't need six speeds.
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6 speed gearboxes are a marketing gimic, I don't think my Xantia really needs 5 gears.
The taller top gear helps get a better mpg rating, and the extra gear really impresses the ladies. Ok, I lied about it impressing the ladies [;)]

tomsheppard
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Post by tomsheppard » 04 Sep 2005, 02:17

Entirely because modern cars don't have enough torque. You speak of the middle of the torque band.
I refer to a flat torque curve.
More cogs mask the inadequacy of modern engines (Sixteen valve four cylinder diesels and suchlike complete poppycock).
Repeat after me: "There ain't no substitute for cubic inches."
I never saw a Cobra with a five speed box; come to that, I never saw an Allard with a four speed box. Either will whip a tuned Seat, I'm sure, and the Allard will be damn' near sixty years old..

bencowell
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Post by bencowell » 04 Sep 2005, 11:57

You're right about 4 cylinder 16v diesels. I drove a newish BMW 120d and although performance was great if you dropped down one or 2 of the notchy 6 gears, the in-gear performance was poor, worse than my C5 2.0 HDI 110 which is 50-odd bhp less and has the Xantia engine first sold in 1998 and only minor changes since then.
You had to drive the BMW like a petrol engine, i.e dropping gears and keeping the revs high in order to maintain progress.
I haven't driven a new HDI 16v, but probably will do sometime.
How does the new HDI compare to the last generation HDI in terms of low down torque, in gear performance and the relaxed diesel feeling?

user_3150
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Post by user_3150 » 04 Sep 2005, 15:24

Having had my ECU remapped I would recommend doing it. I've gone from 90 to 115. Which has improved torque, power and fuel economy. I think the best bit are the revs available. Before it would get sluggish at 3000 rpm but now it will carry on past that with ease (this is good for overtaking and pulling out of busy junctions. I didn't get it done for the extra power but more for better economy so the power is a bonus.

FrenchLeave
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Post by FrenchLeave » 04 Sep 2005, 21:55

Qoute from S14yer "I remember when cars only had 4 gears - now at least 5 is standard. Is that because modern cars don't have enough torque?"
No, but they do have a peakier torque curve and cars have a much wider speed range.

Sl4yer
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Post by Sl4yer » 04 Sep 2005, 22:51

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by FrenchLeave</i>

No, but they do have a peakier torque curve and cars have a much wider speed range.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Yes, I know that. I was replying to Tom who seems to think that cars have too many gears, because they don't have enough torque. And that we should all drive around in gas-guzzling V8s to avoid changing gear so often.
Modern cars are about compromise. Both the Leon and the Volcane are good compromises of space, speed and fuel economy. To compare these with an AC Cobra or an Allard is just plain daft.

tomsheppard
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Post by tomsheppard » 05 Sep 2005, 00:01

No! I think that we should all be driving around in large engined, slow revving cars for comfort, smoothness and economy( miles per car.). To return to the topic, I have an 1800 cc car which at thirteen years old will return fifty MPG or cruise in comfort at 100 MPH averages, carries half a Ton and at 144,000 miles is less than half way through its working life. I completely fail to see the point of tuning it to burn more fuel, tyres engine life and insurance money so that I can get to 60 MPH a second more quickly. If I wanted to do that, I'd buy a faster car (or take off the spoilers and wide tyres together with the 250KG of unnecessary mass!). Of course the losses in the gearbox must sap power so perhaps it is necessary to absorb the inadequacies of the six speed box[;)] My comparison to performance cars from forty and sixty years ago was quite deliberate!

ItDontGo
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Post by ItDontGo » 05 Sep 2005, 01:54

I have to ask why you think you need over 200hp to drive on the road. If you thrash my 50hp Citroen AX you'll end up going well too fast and I'm sure that if you thrash your Volvo at the moment you will end up doing likewise. Motorists who like to call themselves 'drivers' buy stupid fast cars in order to back up their fantasy that they know how to drive as opposed to move a car around in traffic. Whats the fascination of accelerating a little bit harder??? Who are you impressing? In my experience people will just think you're a t_t if you are anti-social and drive too fast.
If you bought a 2CV or a little Fiat 500 you could thrash that in a very satisfying way and get a lot more out of it that you can in a great big Volvo with too much power.

bencowell
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Post by bencowell » 05 Sep 2005, 02:27

I know plenty of Institute of Advanced Motorists members who have tuned their turbo diesels.
My C5 gives slightly better economy when tuned, is even more relaxing to drive, requires fewer gear changes and is a lot quicker than the standard model.
My insurance premium (different companies) came to £3 more chipped than plain. (My chipped insurance company won't cover a standard family hatchback unless you modify it!)
We all appreciate the benefit of frequent oil changes, eg 6,000 miles at half-interval, so there will be little, if any extra cost involved.
I can't see any downside to chipping.

crooser
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Post by crooser » 07 Sep 2005, 01:37

itdon'tgo.i don't know if thrashing a great big volvo was referring to me but if it was here are a few points i would like to mention.i don't thrash cars,to me the volvo is not a big car,if i did over 50 in an ax i would be worrying how to stop it in bad conditions and also worry if i hit anything with it.some of the major points of chipping an engine would be more flexiblity and better fuel economy .a higher top speed wouldn't be my objective,but if it was i know which car i would choose out of the two.