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Dyno curve needed - have a physics class analyze your car



You're welcome to use mine if you like. I've got some extra credit ideas. :)

1977 Scirocco, Twin Screw supercharger, built for SCCA autocross

http://im1.shutterfly.com/procserv/47b4d924b3127cceb1dbfb7cdb6b0000001610

(more info, incl. an A/F curve)
http://forums.vwvortex.com/zerothread?id=1476793

Car weighed 1965 lbs at the time this was done on a near-empty tank of gas. Now
weighs 1940 with a full tank of gas. No engine or transmission changes have
been made.

Tire diameter while on the dyno was 22.7". Tire diameter while racing is
actually 20.6". If predictions can be made about what effect that might have
had on the dyno curve, that would be interesting to see...

Gear ratios are currently using an FF
3.89FD 	3.45 	1.94 	1.29 	0.91 	0.71

If you're looking to make interesting comparisons, I'm planning on switching
to:
3.67 	3.45 	1.94 	1.44 	0.91

(Most autocrosses I encounter have top-speeds in the 50-70mph range, so keeping
2nd and 3rd as usable as possible are key.)

Have fun in class! No matter which dyno you use, take notes and post the
results for us to see!

Neal


--- GGehrke <ggehrke@gmail.com> wrote:

> I'm in a "Physics of Cars" class (a 1 credit elective)
> Our homework is to bring in a Dyno curve for a car we're interested in
> analyzing.  I also need weight, gear ratios (inc final drive), and
> tire diameter.
> 
> If you have a curve from your car and you'd be interested in finding
> out where your ideal shift points are (I'm pretty sure that's the
> point of the exercise, I'm actually not sure, I had laser eye surgery
> like 6 hours before class last week and though I was hardcore and
> went, it was a terrible idea and I was in no condition to pay any sort
> of attention, but I digress) and other fancy scientific numbers for
> your car, send me a copy of the curve.  I don't really feel like using
> a generic R&T published graph for some new car that I really don't
> care about.
> 
> I'd like to find an 8V Mk1 (like mine) but any rocc will do.  If you
> don't have the weights and such I'll find close numbers online.
> 
> If it really seems helpful, I'll post a synopsis and step by step of
> what we did to the list when I'm done.  I think it's going to be basic
> area under the curve type stuff.
> 
> Due thursday afternoon.
> 
> -Grant-
> 
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