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Old 18th May 2005, 20:12   #1
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Default Engine Output and Torque power

I found the following in technical specs of Zen

Engine Output: 60@6000 and Engine Torque: 8@4500

I was tempted to compare with Santro

Engine Output: 62@5500 and Engine Torque: 9.1@4000

What this actually means. I think that more BHP, its more pick up. What is the role of the figures mentioned after @

What is engine torque means. How do you arrive that the combination is better
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Old 18th May 2005, 20:17   #2
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Quote:
Originally Posted by Surprise
I found the following in technical specs of Zen

Engine Output: 60@6000 and Engine Torque: 8@4500

I was tempted to compare with Santro

Engine Output: 62@5500 and Engine Torque: 9.1@4000

What this actually means. I think that more BHP, its more pick up. What is the role of the figures mentioned after @

What is engine torque means. How do you arrive that the combination is better
The figures after the @ refer to RPM. Therefore the Zen has a peak power of 60 BHP and this power is generated at 6000 RPM.

At any RPM, your pick-up is proportional to the Torque at that RPM. Power (BHP) is calculated as Torque*RPM / Constant (I think the constant is 5250, don't remember for sure). So an engine that generates high-torque at high RPM (ie revs freely) will have high power. This is why petrol engines have higher power figures than diesels, but because diesels have higher low-end torque, they may be more driveable in city conditions.
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Old 18th May 2005, 20:26   #3
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Originally Posted by johnjacob
So an engine that generates high-torque at high RPM (ie revs freely) will have high power.

If we compare Zen and Santro, the torque of Santro is higher than Zen, but at RPM comparison Zen has higher figures than Santro. In this case which one is more powerful.

Iam I getting wrong?
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Old 18th May 2005, 20:28   #4
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Quote:
I think the constant is 5250
The constant is 5252.

Quote:
Power (BHP) is calculated as Torque/RPM * Constant
BHP = torque * rpm / 5252.

Quote:
I found the following in technical specs of Zen

Engine Output: 60@6000 and Engine Torque: 8@4500

I was tempted to compare with Santro

Engine Output: 62@5500 and Engine Torque: 9.1@4000
Quote:
How do you arrive that the combination is better
Well, technically speaking. the figures on the Santro would be more ideal as you're achieving more power and torque at lower rpms but, there are other factors that can affect this.

1. Gearing
2. Loss of power between flywheel and wheels.
3. Weight of the vehicle
4. Rolling resistance
5. Aerodynamics etc

On paper, the Santro looks impressive but, it's not the case when you actually drive it.

This site should be able to explain better : Torque and Horsepower

Shan2nu

Last edited by Shan2nu : 18th May 2005 at 20:31.
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Old 18th May 2005, 20:41   #5
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When you calculate horse power, you have to remember that torque is always calculated in foot-pounds (lbft).

Zen - 8kgm = 78.48nm = 57.88lbft

Santro - 9.1kgm = 89.27nm = 65.83lbft

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Old 18th May 2005, 20:48   #6
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Quote:
Originally Posted by Shan2nu

BHP = torque * rpm / 5252.
Man, you're FAST! I caught the error and edited my post, but by that time you had already posted

Last edited by Domnic : 18th May 2005 at 22:24.
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Old 18th May 2005, 20:50   #7
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Quote:
Originally Posted by Surprise
If we compare Zen and Santro, the torque of Santro is higher than Zen, but at RPM comparison Zen has higher figures than Santro. In this case which one is more powerful.

Iam I getting wrong?
The RPM per se doesn't matter. What is important is the torque curve - the car that generates high torque over the largest range of RPM will be faster. Also remember that the weight of the vehicle (power-to-weight ratio) comes into play here.
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Old 18th May 2005, 20:53   #8
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May, you're FAST! I caught the error and edited my post, but by that time you had already posted
Thats bcoz we've gone through this torque and horsepower theory so many times, that I don't even need to think twice about it. LOL

BTW, here are 2 more threads on similar topics.

1. Torque and Horsepower (Torque vs BHP?)

2. Torque, Horsepower and Speed (Torque, HP, Speed)

Shan2nu

Last edited by Shan2nu : 18th May 2005 at 21:16.
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Old 18th May 2005, 21:23   #9
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guyz i own both santro xing and 97 carb zen the pik up n power of my zen is much more than tht of my xing my xing refuses 2 go above 135....both r stock
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Old 18th May 2005, 22:10   #10
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guyz i own both santro xing and 97 carb zen the pik up n power of my zen is much more than tht of my xing my xing refuses 2 go above 135....both r stock
Why that, drive the Alto and the Wagon R (which are supposed to have the same engine) and you'll se a world of diff between the way these 2 perform.

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Old 18th May 2005, 22:35   #11
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Quote:
Originally Posted by Shan2nu
Why that, drive the Alto and the Wagon R (which are supposed to have the same engine) and you'll se a world of diff between the way these 2 perform.

Shan2nu
couldnt get that. Are you talking about the discontinued 1.1 Alto?
If so, whats the difference you are talking about? I thought both performe equally well.... please elaborate
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Old 18th May 2005, 23:11   #12
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If so, whats the difference you are talking about? I thought both performe equally well.... please elaborate
Nope. Their performance is not the same. While the Alto used to finish 100kmph in 14-15 secs, the Wagon R takes 17 secs.

Then there's also the drivability, the Alto feels much more peppy compared to the Wagon R.

And i dunno if you've noticed it. The Alto engine seems to be more revv happy than the Wagon R. Dunno what causes this.

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Old 18th May 2005, 23:30   #13
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Quote:
Originally Posted by Shan2nu
Nope. Their performance is not the same. While the Alto used to finish 100kmph in 14-15 secs, the Wagon R takes 17 secs.

Shan2nu
Wagon R take 14.31 sec for 0 t0 100.acc to autocar

Last edited by merve_extreme : 18th May 2005 at 23:31.
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Old 18th May 2005, 23:34   #14
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Wagon R take 14.31 sec for 0 t0 100.acc to autocar
Can't believe anything Autocar says. They say the Corolla is faster to 100kmph than the Skoda RS. they say the OHC 1.5 has a higher top speed than the OHC Vtec.

Autocar figures are the last thing you should look at.

ANyway, this isn't a OD vs ACI discussion so, lets stick to the topic.

Shan2nu

Last edited by Shan2nu : 18th May 2005 at 23:40.
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Old 20th May 2005, 21:00   #15
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Shan, I've seen a WagonR do a sub 15.5 sec 0-100kph run. Dead stock. 17 seems a bit high.
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