4.56 gears?

[Mike97ZJ]

Thanks for the info.

2K rpm at 70mph, that's pretty low. That's pretty good highway gearing, though. Any lower than that, and the engine would start to bog and the tranny would be kicking down all the time.

That's a good idea, about running with the OD off to see if higher gears will be tollerable. I think they have a 30% OD, so if the gears you were looking at were 30% lower, it would give an exact idea of how it would be. I'm lowsy at math, so I can't figure out what gear ratio running with the OD off would be equal to.

And I hear you about gas mileage dropping as speed increases. I have an instant economy readout in my Jeep, and I notice the same thing.

At 60-65mph, I can get about 18-20mpg, depending on how flat the road is. If I step it up to 70mph, I get about 15-16. Needless to say, I drive alot slower now, and usually set the cruise to just under 65.

BTW, I turn around 2300 RPM at 70mph.

My old 98 Firebird with the six speed turned 2k rpm at 80mph in sixth gear. That car would get about 28mpg on the highway. Of course at much under 80, that sixth gear was useless, because the motor would just bog and the car would not accelerate at all.