What's More Important

[WARLORD]

whats more important a cars kw or the torque it makes.

for eg 260kw 689 nm or 250kw 760 nm

[The Mafia]

250kw 760 nm would be heaps more fun to drive

[Green_s13]

it all depends where the torque comes in if the 760nm is coming on at 7000 rpm and the 689 is coming on at 4000 rpm then i would prefer to have it come on at 4000rpm with less torque as it is more usable

[Thunderbolt]

Well KW is directly related to torque anyway.

Here is the formula if you are interested: kW= torque x rpm / 9549

[sh@un]

Important for what?

Tractability or outright pace?

The car that holds on to the most torque at high revs (and therefore has the most power) will be quicker in every track racing discipline that counts.

You'd be better off with more low down torque (i.e under 3500 rpm) in a pure street car, and sacrificing ultimate top-end power in a pure drift car to obtain better throttle response/adjustabilty in the 4000-7000 rpm zone.

A few disclaimers here, but comparing cars of roughly similar aero C.D's, and both with the correct gearing to suit the power delivery characteristics/launch traction/engine rev range- The car with the best power-to-weight ratio (not the most torque) will always have the quickest E.T at a drag strip.

Anyone that tells you differently is either ignorant or stupid.

[sh@un]

Well KW is directly related to torque anyway.

Here is the formula if you are interested: kW= torque x rpm / 9549

You're right there.

Here's a scenario- You could have an mildly modded old low tech, big cube, push-rod 2 valve V8 that made the same torque at 4500rpm as a worked RB whatever, but what happens to the V8 the harder you rev it? In most cases, the torque curve drops off like you just pushed it over a cliff, and therefore the car is no faster when revved. The 'Line on the other hand has just started to come on boost hard, and holds or increases that torque value for 1000's of rpm more- thereby having a much higher power and torque level in the upper rev range than the V8. And thereby giving better acceleration when launched correctly.

[zebra]

Yeah But, (theres always a but lol)

If the skyline is just starting to come on boost hard at 4500rpm the V8 wouldve hosed it off the line, be more responsive outta corners.

Drops off like a cliff, Tell that to the NASCAR guys whose Old School 'Clunkers' sit on 10000RPM for hours on end and are still tractable around the pits and can smoke the tyres from 3000rpm in 3rd.

Try That in a 2.5L turbo 6

As they say torque wins races horsepower sells engines

my 2c

Andrew

[sh@un]

Yeah But, (theres always a but lol)

If the skyline is just starting to come on boost hard at 4500rpm the V8 wouldve hosed it off the line, be more responsive outta corners.

Drops off like a cliff, Tell that to the NASCAR guys whose Old School 'Clunkers' sit on 10000RPM for hours on end and are still tractable around the pits and can smoke the tyres from 3000rpm in 3rd.

Try That in a 2.5L turbo 6

As they say torque wins races horsepower sells engines

my 2c

Andrew

no, no and no

with the right launch technique, the 'Line would be at the right revs to be on boost straight away anyway. Harder to acheive at very high power levels, yes, but still achievable.

more responsive outta corners? not if you can use a lower gear effectively and keep the revs up (admittedly not as easy/relaxing as using a higher gear and the low down torque in a V8)

and what relevance does a fully CNC machined, ultra high nickel content block, custom built everything NASCAR V8 have to an old warmed over road-going Ford/Chev V8? absolutely none. cheers

torque wins races eh? not if someone else has a higher average torque in the upper rev range (ie. more power)

[zebra]

hehe I was waiting for a flaming.

For a Daily I would still prefer a lazy V8 any day.

I love my skyline and love the feeling of the boost rush.

Its all very much to do with the way the car delivers the power in my opinion.

What I ment by being by responsive outta corners is that if a turbo car delivers its power like a like switch its just gonna wheel spin and then when you back off to get some grip, you lose boost and basicly have to start all over again.

I know thos from the drag strip where when i lifted off in second i nearly headbutted the windscreen, as It dumped all boost, then had to wait for the system to repressurise before it would take off again.

Wheres watching the NA cars, they just had to lift enough to stop the wheels spinning aand they were straight back on it.

Gearing also plays a big part with that too, if you had close ratios, like you say you could always be in the power band,

Unfortunatley not all of us have the dollars to buy a Hollinger Box with 10 different ratio sets (When I win lotto I will)

But Hey, Much to a muchness I guess, everyone has a differnt opinion and there Entitelled to it and thats what Forums are about isnt it? voicing opinions about different subjects and not flaming somone because I mentioned NASCAR

Andrew

[khunjeng]

dunno torque doesnt win the race...it helps a whole lot though. I'II take a good driver myself!

[WARLORD]

o my god what have i started ,the reason ive asked is because i made a air box cover one drunken night with a mate and it sat too close to the filter and my dyno run today gave me more down low and more in the mid range and at the top it dropped off up high because of the dumb mod i did. By the time we figured it out it was the air box cover it was all ready off the dyno it would of hit the 270+ and more torque. By the look of the graph the numbers where 259kw@754-250kw@790 the top post was an eg today it made more torque all the way thru and died at the last 1700rpm because of the air box restricting.ill fix it and run again .

thanks guys for the replies.

[courier33]

My R33 manual has 178 kW ATW and 529 NM, I also have an XE 351 automatic with 196 kW and 850 NM of torque ATW and the Syyline still beats the XE in a drag with me and my missus. Ill drive the XE in traffic anyday. Gear changes are not so necessary when theres heaps of torque.

[heller44]

Do you have the dyno graphs to compare the area under the curve of the rb and clevo? I am just interested is all.

[Adriano]

it all depends where the torque comes in if the 760nm is coming on at 7000 rpm and the 689 is coming on at 4000 rpm then i would prefer to have it come on at 4000rpm with less torque as it is more usable

Yes, but the 760nm at 7000 is going to make a lot more KW than the 689 at 4000, WHat you are really looking at is the shape of the torque and power curves, the more like a big fat hill the better the drive, ski ramps are only good for drag cars with close ratio boxes or autos

[Thunderbolt]

My R33 manual has 178 kW ATW and 529 NM, I also have an XE 351 automatic with 196 kW and 850 NM of torque ATW and the Syyline still beats the XE in a drag with me and my missus. Ill drive the XE in traffic anyday. Gear changes are not so necessary when theres heaps of torque.

It's not so much the torque the XE produces but where it is delivering it. To have 178 @ wheels in Skyline and a lowish torque figure, means that it is producing maximum power higher in the rev range. If the XE was producing the 850NM at the same rpm then power would be a lot greater, so this tells you that is producing it's power lower in the rev range. When you are cruising around the street you would find that it is in the sweet spot in the rev range, hense the reason why you don't need to change gears.

Edited July 22, 2007 by Thunderbolt