transmission or gears for better highway driving

[vipergtrdj]

This past weekend I drove in a friends NBS chevy, and noticed he could do around 75-80mph on the highway and still be around 1500-2000rpms in overdrive. It rode a ton nicer then mine as well, I was just curious if it was just a matter of gears, or a better transmission to get mine to drive better on the highway. (My gears are 3.73 and 4L60E vette servo).

Right now, at around 2000-2500 my truck struggles to be at 75-80, and doesn't really stay there unless my foots is constantly on the gas. I don't have the specs on my friends NBS. I know its a V8, 1/2ton, 4x4.

 

[Blue95]

I have the same setup in my '95 with 285's though, it's just that your pushing alot of weight, with a lot of wind resistance with about 30HP less and less torque as well.

 

[vipergtrdj]

well that kinda sucks.... I got pretty comparable mods to yours - cept you have the E-fans. Did you notice a difference when you switch to e-fans by any chance? I have been undecided on doing that mod for about 3-4months now.

I wonder if the power difference really makes that big of a difference..... Altho if you wanted to cruise on the highway thats why cars were invented haha (my 00 passat does good on the highway, but its not my truck )

 

[Blue95]

Meh its an ok difference, It wasn't really worth the hassle but if you want every HP you can get then its a good mod.
Well you are pushing alot of air at 75-80, 2200-2500 is the best cruising RPM for a TBI engine, it is just how it is.

 

[vipergtrdj]

hmmmm ok. I will have to sit on it until after winter I guess. As for the highway and gearing, I guess I will just stick with what I have. Kinda sucks the newer trucks are better for cruising on the highway tho.

 

[Blue95]

Well you can always regear to 4.10's, 4.30's or 4.56's

 

[vipergtrdj]

hmmmm I will have to read on the gearing some more. I think I will stick with 3.73's for now. Maybe once I fix my fuel pressure issue it will do a lot better on the highway hehe (just installed the gauge today so time to find the solution for it).

 

[Blue95]

Mine is set at 14 with all my mods, and it needs to be turned down

 

[dirtyhick42]

My nbs has 3.42s with 315/70/17s and when I am at 80 mph I am just a hair under 2000 rpm's. GPS speed not speed-o speed. I haven't noticed a huge difference compared to my two past obs's though. But I did also drive an 06 gmc nbs on a daily basis when I had those trucks so it wasn't a huge change for me.

 

[woody80z28]

You should both have 4L60Es, so the difference in RPM must be from tires and/or gears only. I would think that your truck should run better at more than 4psi though. haha

Going with steeper gears will help with the torque, but raise your cruise RPM, so that's not what you want to do. Your friend must have much taller gears than your 3.73s...maybe 3.08s?

FWIW, I think 3.73 is a good all-around gear. That's what's in my truck and they're staying.