I'm in a disagreement with a buddy of mine here. He drives a C5 vette with a 6 speed and cruises at an RPM between 2300-2600 (let's say 50-55 or so mph in 4th gear). Isn't it ideal motor speed of these ls1s, for fuel economy and such, to cruise at RPMs of 1200-1900? I do that and the car reacts just fine with plenty of low end torque to pull me along. Who is right here?

 

actually i cruise at speeds from 1900-2500 rpms, i shift at 2500+

 

he'll more then likely start getting blowby. rpm without load sucks oil thru the piston rings

 

un needed high rpms = bad gas milage and more wear and tear. Its the laws of physics.

On a side note, it would be nice to know what speed it is in 6th gear that you get the best gas milage at.