madteg
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posted on 26/11/07 at 06:30 PM |
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power to weight (how)
Does anyone know how to work out power to weight. thanks.
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indykid
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posted on 26/11/07 at 06:36 PM |
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quite simply.
you divide the power of your car by the weight:p
as for getting the figures, a weighbridge and a rolling road are about your best options.
have a look at some of the online calculators or data websites if you have a standard engine for the power output.
tom
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keithice
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posted on 26/11/07 at 06:49 PM |
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Take the weight and find the number required to multiply to take it to a tonne.. then multiply the horsepower by the same amount...
example:- a car weighs 635 kgs with 221 bhp, so
1 tonne divided by 0.635 tonne = 1.574 approx.. so 221 bhp times 1.574 = 347.854 bhp per tonne...
Smile and wave boys.... Smile and wave....
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snapper
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posted on 26/11/07 at 06:49 PM |
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Metric Tonne is 1000 Kg
Your car is 600 Kg
Your BHP is 150.
Divide 600 X 150 = 0.25 and multiply by 1000. = 250 BHP per Tonne
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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mat.price
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posted on 26/11/07 at 09:12 PM |
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the way i work it out is
metric tonne is 1000kg or 1
your car is 600kg or 0.600 of a tonne
your bhp is 150 per tonne
so 150 bhp divided by 0.600 should work out the output of the car
150 / 0.600 = 250 bhp per tonne
hope this help in some way![](/images//smilies/bigsmile.gif)
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Dale
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posted on 27/11/07 at 01:12 AM |
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Maybe its just me but in cars this light , the drivers weight should be included. But that is just me.
Dale
Thanks
Dale
my 14 and11 year old boys 22
and 19 now want to drive but have to be 25 before insurance will allow. Finally on the road
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Paul TigerB6
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posted on 27/11/07 at 01:24 AM |
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quote: Originally posted by Dale
Maybe its just me but in cars this light , the drivers weight should be included. But that is just me.
Dale
In cars this light the driver's weight will certainly be a bigger influence than a heavier car with more powerful engine when comparing
performance and power / weight ratio I agree.
For pub bragging rights though - got to really stick to a level playing field so no driver weight added.
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DarrenW
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posted on 27/11/07 at 11:31 AM |
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If you are trying to compare your cars spec to known production cars then just use the wet weight. ie full of fuel and fluids but no driver.
If you want to know the overall on road figure then use wet weight plus driver.
Most people use wet weight minus driver.
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alfasudsprint
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posted on 27/11/07 at 11:33 AM |
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I think many weights quoted are pretty much dry, only incl a few vital fluids.
Tim
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wicket
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posted on 27/11/07 at 12:32 PM |
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SVA weight is all fluids, full tank, no driver or passenger.
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Hellfire
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posted on 27/11/07 at 12:46 PM |
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The standard SVA test does not give you a true vehicle weight (unless you specifically ask for it) It merely weighs individual axles.
Phil
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Paul TigerB6
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posted on 27/11/07 at 01:24 PM |
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quote: Originally posted by Hellfire
The standard SVA test does not give you a true vehicle weight (unless you specifically ask for it) It merely weighs individual axles.
Phil
Any idea by how much the wet weight at SVA which weighs the axles individually for calculating brake efficiency would be different to the true wet
weight??
Learn something new every day!!
Cheers
Paul
[Edited on 27/11/07 by Paul TigerB6]
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jrevillug
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posted on 27/11/07 at 09:53 PM |
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surely adding the axle weights will give the wet weight?
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flak monkey
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posted on 29/11/07 at 07:47 AM |
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quote: Originally posted by Hellfire
The standard SVA test does not give you a true vehicle weight (unless you specifically ask for it) It merely weighs individual axles.
Phil
Its not far out though. The only error comes from the car sitting at a stupid angle when in the rollers. If the rollers were at floor level so the car
sat level then the sum of the two axle weights is the total weight of the car. Irrelevant of where the centre of gravity is in relation to the
axles.
If you want a spot on weight, you need to take it to a weighbridge, but the sva weight is not far out at all.
David
Sera
http://www.motosera.com
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