calculating Torque

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musty1
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calculating Torque

Post by musty1 » Fri May 25, 2007 5:58 pm

To all you brainy people,

Can anybody tell me how to work out what toqure a engine will do?
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MCB
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Post by MCB » Fri May 25, 2007 6:40 pm

There you go...
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Philws4
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Post by Philws4 » Fri May 25, 2007 7:41 pm

Or if you have VAG COM then view/log channel 120 whilst doing some runs in 3rd gear.
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musty1
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Post by musty1 » Sat May 26, 2007 8:21 am

cheers mate
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dazzer
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Post by dazzer » Sat May 26, 2007 9:14 am

MCB wrote:There you go...
Is that in Nm or lbs/ft? :roll: Sorry - guessing it's lbs/ft.
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Post by MCB » Sat May 26, 2007 9:39 am

No worries and you guessed right.

And just in case anyone is interested, where does 5,252 come from?

HP = 550 foot pounds per second

Engine RPM = 0.10472 radians per second

550 divided by 0.10472 = 5,252
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dazzer
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Post by dazzer » Sat May 26, 2007 10:05 am

Eee your'e just too quick - my next question was re the constant.

Anyone remember what point on the RPM peak torque occurs on a standard S4?
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MCB
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Post by MCB » Sat May 26, 2007 10:17 am

Taken from the Audi S4 Engine PDF:
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dazzer
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Post by dazzer » Sat May 26, 2007 10:30 am

Thanks:

1 Lb-Ft = 1.35582 Nm.
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Post by MCB » Sat May 26, 2007 10:54 am

:thumbs:
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bobbler
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Post by bobbler » Sat May 26, 2007 11:01 am

Heres an MRC custom remap for you too ;)

http://www.ryanopie.com/rollingroads/31.jpg
. S4 Nogaro Blue Avant . ECS IV . RS4 handling bits . 18" Ultraleggera . AWE Boost Gauge . MRC Custom Map . 315 BHP . 482 Nm .
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Post by S4TAN » Sat May 26, 2007 1:09 pm

Interesting stuff ...

Anyone know at what revs a K04 car (+ big injectors, no pre-cats or cats, RS4 i/c's, MRC custom re-map etc) would make its peak torque ... ?
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MarkB
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Post by MarkB » Sat May 26, 2007 1:12 pm

S4TAN wrote:Interesting stuff ...

Anyone know at what revs a K04 car (+ big injectors, no pre-cats or cats, RS4 i/c's, MRC custom re-map etc) would make its peak torque ... ?
No idea, but I'll be taking mine to the Janspeed Rollers again in the not too distant future. Be great to see yours on there...
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Post by S4TAN » Sat May 26, 2007 1:52 pm

No idea, but I'll be taking mine to the Janspeed Rollers again in the not too distant future. Be great to see yours on there...
I'm up for that Mark - Doug estimated mine to be about 430bhp/480ftlb ... so adjusting the formula to:

RPM = (5252xbhp)/torque gives peak torque at ~4,700rpm ...

It "feels" like i'm getting peak torque a bit lower than that in the rev range (maybe 4.5Krpm), which puts me around 500ftlb... highly unscientific i know - so will be good to get it on the rollers and get some more definitive figures ... see how close Dougs estimate is.

Let me know when you're going ...
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Post by GrahamS4 » Sat May 26, 2007 1:58 pm

Get down to Aylesbury Julian, it's only local - dyno dynamics dyno same machine type as I see Doug and Mihnea's latest power runs were done on and also used by myself KayGee recently and DavidT in the past.

Comparing your and KayGee's car would be a good comparison.
Present: 2010 Ice silver B8 S4 s-tronic saloon (standard)
Past: 1998 Agate grey B5 S4 saloon (MRC tuned)
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