Safe operating RPM's

[Weasel73240Z]

I have a 5-speed to go into my 73, but I don't have the free cash right now to have it rebuilt. I actually enjoy driving the car around the city with the 4-speed/4.11 combo, but it revs awfully high on the highway. I'm going to have the 5-speed rebuilt next Winter, but it's just not in the budget for this season, after a whole bunch of non-car expenses cropped up this year.

My question is, should I be concerned with driving the car at 3,500 - 4,000 RPMs for an hour or so on the highway? Of course, that's only 1/2 way to the redline, but I just feel like I'm pushing the car too hard when I drive it at 65 or 70 mph for long periods of time. Am I being overly protective of my beloved Z? Any input would be appreciated.

[Carl Beck]

If your L24 is in good shape to begin with - You won't hurt it a bit... but your gas milage won't be anything to write home about..

FWIW,

Carl B.

[d240zx2]

Ditto what Carl said. 4 grand is loafing to an L engine.

[Weasel73240Z]

The motor is tight as a drum, only 28,000 original miles, and it runs great. I guess it just sounds to me like I'm pushing it really hard at 4,000+ on the highway. Probably because I've always owned torquey, American V8's before the Z.

Gas mileage is no concern. I drive the car pretty hard, and usually have my right foot jammed pretty hard into the accelerator. I only drive the car in nice weather, once or twice a week, and nice weather in MA lasts about 4 months at best. I think last year I put 1,050 miles on it.

That's for the input guys. I'm gonna swap in my RT diff. mount and keep the 4-speed for 1 more season.