@65mph, 31s/4.38s will turn 2622RPM in 5th gear, while 35s/4.88s will have the engine at 2588. less than 100RPM difference, however with my engine set up the way it is, i use 4th gear a lot more than with a 22R head as my engine's powerband comes in slightly higher and goes up farther. engine's actually quieter and gets better mileage when i drop a gear.
