Legacy Speed Calculator

[Legacy777]

Put together a little spreadsheet that will calculate the theoretical top speed of the first gen Legacy.

http://main.experiencetherave.com/subar ... ulator.xls

From my own experience in my Legacy, I think these may be a little inflated. While I was AT & FWD, each gear would give about a 40 mph increase in speed. But you can use this to estimate a top speed. You can change the engine RPM and rev / mile numbers and that will update the spreadsheet.

enjoy

[evolutionmovement]

Not trying to be one of those one-up dicks, but I have a calculator that factors in the aerodynamic drag against horsepower for all kinds of stuff. Helps to have a dyno plot, but it's fun to play with horsepower changes, weight reductions, and possible aerodynamic changes (which are pretty fixed with the Legacy, but I'm using it for my prototype design) and how they affect top speed (the cells change shading if the horsepower required exceeds horsepower available) and mileage (which it also calculates using standard BSFC full-throttle and a lean-burn mode calculation using my own estimated lean-burn BSFC, but seems to test pretty accurately against known real-world cars).

Someone can plug in Josh's numbers for the gear ratios, measure their frontal area and go.

I also have a chart calculating acceleration per gear. There's an additional chart that calculates acceleration change/gear/rpm using a dyno plot, but if I transfer it to another sheet in the interest of readability (my original is filled with notes) it loses all its references, so I won't put that one up. How do I post an Excel sheet?

[Legacy777]

I've seen a couple like that too. I have calculated the frontal area and had drag numbers as well. I'll have to see if I can dig that up.

Email me the Excel file and I will host.

[evolutionmovement]

It started out with something I got from the internet, but I expanded it. I'm not quite sure about my mpg formula in what I sent since I was screwing around a little while ago, but I'm too lazy to check it out. MPG is kind of a tough thing to nail down on "paper" anyway.

[Legacy777]

Here's Steve's spreadsheet

http://www.main.experiencetherave.com/s ... ulator.xls

[SubaruNation]

you guys are awesome

[Legacy777]

Got some more info.

Drag coefficient for the sedans is 0.33.
I snagged drag coefficient from some literature, don't remember where though.

Frontal area is 21.96 ft^2
I calculated this back 2002 based on my Legacy and shining a light from behind on a paper and calculated out the area. So it's probably a reasonably close representation.


Also, snagged this spreadsheet from Nasioc a few years back. It's similar to Steve's.

http://main.experiencetherave.com/subar ... rf_WRX.xls

[magicmike]

lol, nice work guys!

[Legacy777]

I was looking through some old pictures and found the pictures of when I did the measuring and calcs

http://main.experiencetherave.com/subar ... lareacalc/

[SubaruNation]

GANGSTER!!!!

nice work josh