What is the rpm sweet spot for highway driving

MOPEkidD-3 said

Me too i was ranting couldn't help myself...

Back on topic, concerning higher cruising rpms (i'd consider that 3000+) the level of internal friction goes up roughly exponentially with rpm. So at 3000 rpm there's 2-3 times as much power being wasted on friction as at 2000 rpm.

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You need to really re-think this.
He has a low compression 318 with a small cam.
The motor is going to need around 2500+ rpms to keep the torque at cruise speed, no matter if it is 55 or 85 he has to gear accordingly.

As for the OP you already have 3.23 put them in, sounds like you need highway speed.
If you want power stick the 3.91 in.
Why did you make two threads on this?