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Originally Posted by NBoxster
@BruceLee,
I agree with you on points 2 & 3, but these are consequential, not Mechanical, issues to hitting the Rev Limiter, and I took the lister's queery to mean the Mechanical issues.
I disagree with you on item 1. There is no problem running the Engine at these speeds. The engine was designed to operate at this speed. The Performance numbers are derived from this. Peak HP is usually at or near Red Line. It does not increase the wear on the Engine, assuming, as I previously stated, that the overall condition of the Engine is good and that the fluid levels are proper. According to your reasoning, it would be better to operate the car at idle than any other RPM and we know this isn't the case. Engine Cooling and Lubrication are Crank Speed dependent (the Waterpump and Oil Pump are powered off the Crankshaft), so running at higher RPMs insures that these systems are operating at 100%. This is the primary reason why idling your car excessively will induce greater wear.
Plus, the manufacturer most always adds a Fudge Factor when determining a Rev Limit to minimize warranty claims and the like. I once spoke with a Lotus Engineer about my Esprit which hits the limiter at 7,200RPM. He stated that the engine was good for about 9,000RPM before there were any problems. And, that at 9,000 RPM, it was the Ancillaries (Alternator, Waterpump, AC Compressor), not the Engine, which were the limiting factor. He further said that only at about 11,000RPM were there any Engine problems, and this from the valvetrain, not the Reciprocating gear.
@LexusPilot,
I agree with you re. Upshift vs. Downshift. But want to point out that upon downshifting improperly, it is possible to exceed Red Line RPMs, there is no Mechanical safeguard in place to prevent this from happening.
Happy Motoring!...Jim'99
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