rpm at 70 mph

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02-05-2014, 08:47 AM

jydavis

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rpm at 70 mph

building transam it has a 9 inch with a 3600 yank with 373 gears an 26 inch tall tires what rpm at 70 mph should I see. thanks

jydavis

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02-05-2014, 09:15 AM

guppymech

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Plug your numbers in here:
http://f-body.org/gears/

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02-05-2014, 04:55 PM

Z28SteveA4

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I believe I am at 2500rpms at 70mph and at 80mph im at 3000ish same setup as you are saying too

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02-06-2014, 01:54 PM

01ssreda4

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2400 per the stock tach

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02-19-2014, 10:14 PM

joecar

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RPM = MPH * 336 * GR / TD

GR = (trans gear ratio) * (axle gear ratio)
TD = tire diameter inches

RPM = 70 * 336 * (0.696 * 3.73) / 26 = 2348 --> rounds to 2400

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02-25-2014, 08:59 PM

Streetlegal?

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I'm around 2200 at 70 with 4.56s. Granted I have a 6spd but still. That chart says 2100 at 70 for me.

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02-25-2014, 10:01 PM

01ssreda4

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Stock tach isn't 100% accurate.

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rpm at 70 mph

rpm at 70 mph

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