What RPM's Do you normally shift at?
03-31-2004, 03:13 PM
#16
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04-01-2004, 11:46 AM
#18
Some interesting comments on my post. I agree that Porsche engines are well made and are designed for reasonable high rpm use.
But we also have to face facts. High rpms shorten engine life.
1. Friction is a function of distance travelled. When you use sandpaper you rub faster to sand more. At high rpms pistons, etc. travel a greater total distance and there is more wear.
2. Heat is greater at higher rpms. Material strength decreases with higher temperatures and this leads to failures.
3. Material stress is a function of acceleration. Higher rpms mean higher peak stresses. You don't break connecting rods at idle.
I enjoy my Porsche and don't advocate shifting at 2,000 rpm, but make no mistake about the fact that the harder you work it, the shorter it's life. An engine that never starts will last forever and any engine can be instantly destroyed at a high enough rpm.
But we also have to face facts. High rpms shorten engine life.
1. Friction is a function of distance travelled. When you use sandpaper you rub faster to sand more. At high rpms pistons, etc. travel a greater total distance and there is more wear.
2. Heat is greater at higher rpms. Material strength decreases with higher temperatures and this leads to failures.
3. Material stress is a function of acceleration. Higher rpms mean higher peak stresses. You don't break connecting rods at idle.
I enjoy my Porsche and don't advocate shifting at 2,000 rpm, but make no mistake about the fact that the harder you work it, the shorter it's life. An engine that never starts will last forever and any engine can be instantly destroyed at a high enough rpm.
