how to lower rpm range Options

[eldrewado]

hello all, im new here. im looking to save more gas with my 99 gt. i was wondering if there is another differential i could use to lower my cruising rpm.
if i want more power ill leave it in 4th gear. 3000 revs at 60 mph or so seems a little high, granted its good for power.


anyone have any ideas?

[Special_Edy]

The easiest way would be to install wheels and tires that are a larger diameter. I went from 1800rpm to 2400 rpm @60mph on my 64 chevy truck just by switching from 265 75 r15s to 285 60 r15s. Realize that by making the rollout of the wheels larger you will also throw off your speedometer(it will show a lower speed than your actual speed) and there is no telling how it will affect your Anti-Lock Brake System if equipped(in theory it shouldnt because ABS monitors individual wheel speed but hey I'm no expert).
Also I find that smaller wheels/tires tend to make the brakes feel stronger so putting larger tires on may decrease the efficiency of your brakes somewhat.
But its sooo much easier to swap tires/wheels than transaxles and differential gears.

Another mod to consider would be moving your camshafts one notch retarded on the timing belt(you need to pull the passengerside motor mount, remove the timing belt cover and make sure the Camshaft sprocket for the timing belt is one notch behind or slower than the crankshaft.) Retarding the camshafts one notch(maybe 5 degrees) will significantly improve low end performance and torque while decreasing power output at higher RPMs