Folks:
So I go away for a bit and you knuckle heads start up again about transmissions..
Have you not read Terry Nuckles 10 million best selling book, "Trans-Mission, aint like fish'n", captivating guide book on how to set up a proper transmission for your driving needs.
Let me throw in my $100,000 opinion.. (that would be $3 million in Canadian)
all of these parts work in concert:
Rims and Tire size (which nobody mentioned), engine, transmission.
Once you know the exact engine size and specs and the exact size rims and tire size your going to use and never deviate, THEN decide on the gearing and what you want form the transmission, and your driving preferences..
You can go to the weddle gear site and play with the gear ratio calculator
https://weddleindustries.com/gear-calculator
I know you don't want a 5 speed. This will be a big help not only to understand the gear selection and RP but to fine tune your gears to fit your driving needs and get the best from a 4 speed.. It will show you the RPM's for each gear and the gaps.... Its a great tool and was a huge help when I had Scott Sebastian Build my transmission.. Which works well with my tire size, engine and my personal driving needs.
Sorry I went a little Stan G here
Tebs
damn!! my finger hurts from all this typing