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how to calculate the speed of a car?

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how to calculate the speed of a car?

Old 11-07-2008, 04:23 AM
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Phil.Tran
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Default how to calculate the speed of a car?

Does anyone know how to calculate the speed of a car?

i have got a calculate math and tried to get speed of FG 1/5 F1 car and the result: @ 19.93537 MPH.

while FG F1 known can reach at 100KPH !!? what's wrong?


FG gear: clutch pulley 17T / main pulley 48T; layshaft pulley 18T / diff pulley 42T; engine @8000rpm?!



Thanks
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Old 11-07-2008, 04:31 AM
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zip1385
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Default RE: how to calculate the speed of a car?

Why only 8k rpm? That is really low on these types of motors...
Old 11-07-2008, 06:05 AM
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total3d
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Default RE: how to calculate the speed of a car?

yeah 8k is extremely low, might as well idle across a track...
measure out a track, say 100m, or yards. and time you car over that distance. speed= distane/time. simple... its an approximation though.
Old 11-07-2008, 07:07 AM
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Default RE: how to calculate the speed of a car?

here is a speed calculator from Team AE..

http://www.teamassociated.com/racerh.../gearform.html
Old 11-07-2008, 10:53 AM
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mooman007uk
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Default RE: how to calculate the speed of a car?

my clutch is only just engaging at 8000rpm, try doubling it at least.
Old 11-07-2008, 11:02 AM
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slawhammer
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Default RE: how to calculate the speed of a car?

I have seen guys take a small inexpensive GPS hand held and attach it to there RC cars and trucks or buggy....Under 100 Bux like people use for hiking
or hunting to track distance along with miles...It will give current speed read out as well...Also seen attached to bicycle handle bars..
Do a google search for a GPS unit...Just a another thought...AKA Slawhammer
Old 11-07-2008, 11:33 AM
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bsrman14
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Default RE: how to calculate the speed of a car?

Don't use RPM to figure our speed.[:@] The best way is to buy a cheap radar gun.
Old 11-07-2008, 11:35 AM
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Default RE: how to calculate the speed of a car?

Stick a Garmin Forerunner 101 gps unit in it. That will show you max speed
Old 11-07-2008, 12:28 PM
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OLD_SLOW and in the WAY
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Default RE: how to calculate the speed of a car?

layout 88 ft between a couple markers, have your buddy stand back and time the run with a stop watch. if you travel the 88 ft in one second, your doing 60 mph.

or a shorter course is... 44 ft then its 1/2 sec per 60mph

i tie wrapped my garmin Etrex to the cage
Old 11-07-2008, 03:39 PM
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Default RE: how to calculate the speed of a car?

ORIGINAL: OLD_SLOW and in the WAY

layout 88 ft between a couple markers, have your buddy stand back and time the run with a stop watch. if you travel the 88 ft in one second, your doing 60 mph.

or a shorter course is... 44 ft then its 1/2 sec per 60mph

i tie wrapped my garmin Etrex to the cage

you can buy an Etrex super cheap on e-pay for around 60 buck now
Old 11-07-2008, 07:04 PM
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total3d
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Default RE: how to calculate the speed of a car?

you can buy the hotwheels radar gun for around $20aud(convert it...), i bought one and its accurate to +- 2km/h. it works well with full size cars, and bikes, so 1/5 scale shouldnt be a problem.
it is difficult to trap 1/10 scales though...
Old 11-08-2008, 04:41 AM
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Phil.Tran
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Default RE: how to calculate the speed of a car?

If it was G230RC, how many RPM (outer clutch)?

Old 11-09-2008, 12:35 AM
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splcrazy
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Default RE: how to calculate the speed of a car?

you can buy a venom speed meter it works spot on , the hard part is finding a location for the little magnet and sensor pickup , i put one on my jato3.3 and got a max speed of 77kmh , the way it works is you put a ruler on the ground next to the car starting from the rear wheel then move the car forward until the tire has made one complete revolution , then you look on the ruler how long was the distance for that tire to make its revolution , then get the measurment and multiply it with a special number thats on the instructions then get that final number and put it into the meter , after that it gives you accurate speeds of how fast your going .

but thats alot of stuffing around id just buy that hotwheels radar gun and that sounds like a good idea

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