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Discussion Starter #1
To all the mathmaticians and technically minded folks out there...need a bit of help.
Does anyone know how you can calculate an approximate top speed from these 4 parameters;

Weight of vehicle;
Power of vehicle;
Cd and
Frontal area.

Appreciate any help :)
 

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There's a shareware program on the web called CarTest, I have used it and it was within 1 tenth of a second and 2mph on my 1/4 mile time/speed. It does do top speed also but I haven't tested that to be able to compare the accuracy (yet) ;)
 

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Car Test program

I've also used this for my old GT4 and it was quite accurate for 0-60 etc. After my ban I was a bit reluctant to test the top speed accuracy ;-)

You can find it at http://home.earthlink.net/~patglenn/ct.html

Remember it's shareware so do pay up if you're going to use it properly. The only problems I remember with it were that it did over play wheelspin - but then it was based on US cars not really used to active torque split etc

cheers

Iain

PS anyone used one of those Race Technology meters ? Looks like a good low cost toy?
 

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Discussion Starter #5
Thanks for the replies!

Had a go with that program...pretty damn cool! The thing is that I only have the 4 parameters I listed on my first message...and the prog requires a lot more.

Still searching...
 

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It would be good if somoene stuck this on their laptop and brought it along to the next Dyno day. Just a matter of putting the figures in as we go.

Unfortunately I don't have a laptop. Any volunteers?

John
 

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Discussion Starter #9
Hi Hugh...the actual calculations I'm doing are for a scale model my brother has built for his dissertation in aerodynamics. Looks like we sorted it out:)

Cheers guys
 

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Top speeds @ Dyno Day

Mike is bringing a lap-top to the next Dyno Day so we can do theoretical top speeds as well.

Still missing a few bits of information if anyone can help;
Frontal area for R32, R33 and R34
CD for R34

Thanks
John
 

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Discussion Starter #11
John,

If you click the link that Hugh posted in this thread you will see a post I made with all the R34 Cd values(with the different spoiler settings).
 

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I'm almost contemplating taking a picture of my car, front on, and overlaying a matrix. Counting up the squares and working out from there. Oh joy!:(
 

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Discussion Starter #15
If you downloaded the program wsurfa posted the link for, there is all the data you could ever need for an R33 GTR in the database. Unfortunately nothing for the R34....better start counting:( ;)
 
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