Mean Piston Speed
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From: Palm Harbor, FL
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From: Land of Cincinnati Chili
Originally Posted by Gigdy' timestamp='1310564658' post='20774412
How much extra torque does having the highest mean piston speed give the s2000? Oh right, none.
Torque is a function of displacement. The S2000 has a low displacement. What's so difficult to understand?
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From: Palm Harbor, FL
The AP2 has equivalent AP1 piston speeds at ~8330 RPM.
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From: Houston, TX
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From: Palm Harbor, FL
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From: Maggie Valley, NC
Originally Posted by G' timestamp='1310514406' post='20772903
[quote name='overst33r' timestamp='1310504424' post='20772366']
Actually Audi's V10 for the R8/Gallardo has the higest piston speed of any current engine at 26.91 m/s. It has a fuel cut at 8700RPM.
Actually Audi's V10 for the R8/Gallardo has the higest piston speed of any current engine at 26.91 m/s. It has a fuel cut at 8700RPM.
[/quote]
Really? I think we need to fact check that on the F20. I belive the fuel cut off is at 9200rpm.
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From: Charleston, SC. \>
Originally Posted by takeshi' timestamp='1310589423' post='20776174
[quote name='Gigdy' timestamp='1310564658' post='20774412']
How much extra torque does having the highest mean piston speed give the s2000? Oh right, none.
How much extra torque does having the highest mean piston speed give the s2000? Oh right, none.
[/quote]
Everyone acts like because the pistons move fast this engine is the love child of Jesus and Bernie Ecclestone.
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From: Palm Harbor, FL
Originally Posted by overst33r' timestamp='1310589867' post='20776210
[quote name='takeshi' timestamp='1310589423' post='20776174']
[quote name='Gigdy' timestamp='1310564658' post='20774412']
How much extra torque does having the highest mean piston speed give the s2000? Oh right, none.
[quote name='Gigdy' timestamp='1310564658' post='20774412']
How much extra torque does having the highest mean piston speed give the s2000? Oh right, none.
[/quote]
Everyone acts like because the pistons move fast this engine is the love child of Jesus and Bernie Ecclestone.
[/quote]
I see where you are coming from. It's as useless a measure as HP/L, yet people will continue to quote it. Didn't mean to be so snappy, friend.
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From: Queen City, NC
Afaik, and I've been around here a while,
F20 - redline at 8.8k, fuel cut at 9.0k
F22 - redline at 8.0, fuel cut at 8.3k
If you take a close look at an AP1/F20 tachometer, you'll see it goes red just before the 9k mark, showing the actual redline at 8.8k:
or
The F22's IP is the same way, with redline shifted just to the right of the 8k mark.
Regardless, dynos show how the two engines behave. As others stated, Honda set the rpm to max based on piston speed, and since the AP2 engine's pistons move faster at relative rpm, it has the lower rpm limit.