How often do you redline your Z? Is it bad for the car?

Jordo!

You can't beat entropy... all mechanical systems will fail...

An engine's "redline" is essentially the maximum RPM in a given gear where peak torque and power have been surpassed, and now the engine is producing less useful work and and more heat, further contributing to (eventual) mechanical failure.

Running any engine at or beyond redline for long periods of time can kill it in short order -- consider the planned teardowns for dedicated racecars than run the car to its limits all the time.

But, you are not running the car for sustained periods into the red -- you are shifting at or below the (more or less empirically established) redline.

Pick any gear and drive all the time past the line, well into the red for sustained periods, and you will kill the engine; on a related note, run the RPM's high enough (well beyond redline), and you'll break the oil pump.

On that note, if you shift the car at redline frequently, while it will put more wear and tear than never running it hard at all, it would also be a lot less fun if you never ran it up to its limitl. In other words, stop at the limit, don't hang at it for a while or go beyond it.

Will a "babied" car last longer? Sure. Likewise, a machine that never runs also won't break, but it won't produce any any useful work either.

On a well maintained modern engine, you might see well over 250K miles on it; on one that is run hard, but not beyond the established boundaries, maybe 150K.

You'll probably buy a new car before that anyway.

So, in short, beat on the car as you like (within the limits with which it can be logically beaten), do the regular maintenance, and you should be fine.

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