Can you make more power without increasing torque? - Alfa Romeo Forum
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Can you make more power without increasing torque?

Simple question.
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Simple answer, yes.
 
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Power = torque x revs (more or less), so raising the rev limit will get you more power at the top end.

See Honda VTECs, Mazda rotary engines and F1, for example. This is also how touring cars can get 270+ bhp out of a two litre naturally aspirated engine - the trade off is a drastic reduction in the engine's lifespan.
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So you can, but you need more revs?
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yes

power [kW] = 2 * PI * torque [Nm] * rpm / 60 / 1000
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For example, if your car made 200lbft at all revs, it would be making the following power:

1000rpm = 38bhp
2000rpm = 76bhp
3000rpm = 114bhp
4000rpm = 152bhp
5000rpm = 190bhp
6000rpm = 228bhp
7000rpm = 266bhp
8000rpm = 304bhp

In real life what tends to happen is torque output drops as revs rise, leaving you with a point in which revving more doesn't give you any more power..
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Torque output drops with higher revs due to lower combustion efficiency and engine inner loses increase.
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You see, my mate has just bought a corsa VXR and he keeps banging on about it being the 'Arctic' which has a different (fart) exhaust and has 15bhp more (204bhp). Looking at parkers figures, the arctic version has more power but the same torque output as the normal version and has the same 0-60 and top speed.

So I'm confused as to where vauxhall have pulled this 15bhp out of the bag? If the arctic version has more revs the top speed should increase by a few mph's no?

As for the corsa itself, not a bad little car although not the kind of thing I'd go for. In reality, is only as quick as my modded diesel on the local bypass' etc and it doesn't even have a water temp guage
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It's also like how rally cars keep to the homologated 300bhp but have not restraints n torque so they can have anywhere between upto roughly 700Nm!

the 2008 WRC Subaru Impreza has 650Nm but only 300bhp.
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Quote:
Originally Posted by Singularity View Post
You see, my mate has just bought a corsa VXR and he keeps banging on about it being the 'Arctic' which has a different (fart) exhaust and has 15bhp more (204bhp). Looking at parkers figures, the arctic version has more power but the same torque output as the normal version and has the same 0-60 and top speed.

So I'm confused as to where vauxhall have pulled this 15bhp out of the bag? If the arctic version has more revs the top speed should increase by a few mph's no?

As for the corsa itself, not a bad little car although not the kind of thing I'd go for. In reality, is only as quick as my modded diesel on the local bypass' etc and it doesn't even have a water temp guage
It's easy. If you look on the dyno below max torque is reached at 3750rpm, max power at 5500rpm. If you increase torque a little at 5500rpm (but not more than at 3750), you'll get still the same top torque, but higher power.



PS. Not a Corsa but modded Astra GTC or so
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So you could have the same peak torque but more torque later in the revs which equates to more horse power?
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Originally Posted by Singularity View Post
So you could have the same peak torque but more torque later in the revs which equates to more horse power?
Eexactly
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