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What's the formula for determining piston speed given stroke, compression ratio and RPMs?

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Old 04-21-2004, 06:23 PM
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What's the formula for determining piston speed given stroke, compression ratio and RPMs?
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Old 04-21-2004, 07:38 PM
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Default iirc 1.8T at 6000 rpm is...
17.28 m/sec! compression ratio has no effect! this is an average not top speed.
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Old 04-22-2004, 06:18 AM
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Default Mean piston speed.....
MPS = (stroke * RPM)/6

where,
MPS is in feet per minute
stroke is in inches

On an S4 (and most Audi engines):
Stroke = 3.40 in

At 7000RPM:
MPS = 3966.7 ft/min = 66.1 ft/sec = 20.2 m/sec
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Old 04-23-2004, 05:15 PM
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(rpm * stroke) will give you total distance back and forth over 1 minute
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Old 04-26-2004, 11:59 AM
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Default MAX piston speed.....
for rod lgth about 2x stroke is 1.6X the mean speed, or 106 ft/sec for your case.

based on formula for piston height vs crank angle.
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