Cruising speed?
 

So mine is a 1972 C20 converted to dually (flatbed).
4.10 rear end
1997 nv4500
225/70/19.5 all around
5.3L fully rebuilt (stock internals)
Pontiac GTO intake and maf

My cruising speed is around 75mph and it got as high as 83 mph. What is yours? I am not looking for 140 mph responses, lol, but just kinda what speed ya'll comfortable in your LS powered truck.

Re: Cruising speed?
 

Aruba I've got about the same setup you have except with a stock 6.0 , I've got the nv4500, 4.10, 235/85s and my cruise is same as yours..75-80

Re: Cruising speed?
 

Awesome!

Re: Cruising speed?
 

6.0 with 4l80E and 4:10 gears 29" tall tires.

60MPH @ 1800RPM's

70MPH @ 2200RPM's

80MPH @ 2600RPM's

Give are take a few depending on road conditions.:chevy:

Re: Cruising speed?
 

-
'67 Panel Truck, Camaro LS1 5.7L/4l60e/3.73 posi/30" tires. I cruise the speed limit which in Iowa is 55mph on secondary roads, 65mph on most 4 lanes, and 70mph on Interstates

LockDoc

Re: Cruising speed?
 

My truck likes 32, and 50 around local roads the best. With the somewhat aggressive way my shifts are setup, those are the sweet-spots. It doesn't like 25 or 45.

On the highway, it'll be fairly happy anywhere from 60-80, with 68 being its favorite spot.

Re: Cruising speed?
 

What kind of #s may I get with an 4.8 4l60e
and 4:56 with 265 75r16 ?

Also what would I be looking at with that setup
Acceleration
1/4 mile
top speed
Give real #s or a 1- 10 rating (1 worst 10 best)

Re: Cruising speed?
 

I have no idea the numbers you would get. The numbers I posted are what I have recorded in my 71 while driving it. The 4.8 may get better are worse who knows.
My 6.0 motor is all stock with headers and a dyno tune in it. The guy said it had 80,000 miles on it when I installed it. I haven't touched it except for plugs and wires and a water pump.
I travel a lot and the truck runs the interstate a lot. I did the power tour the first year I had the motor in it and put 3800 miles on it in 7 days. I drove back from Dells Wisconsin to home in less than 16 hrs which is about 900 miles and we ran 80 MPH are more all day long! That including stopping for gas and eating lunch. :chevy:

Re: Cruising speed?
 

Dukkie, I ran an excel program I have (I will try to attach but don't know that I can so e-mail me if you want).
The numbers for your setup would be in 3rd (1:1) at 70 it would be 3390 rpm, in 4th (.70:1) it drops to 2370
As far as acceleration the first gear in the 4l60s are low so according to my chart if you shift at 6000 rpm you would be running 40 in first and about 80 when you shift from 2nd to 3rd.
Your top speed will be limited to the aerodynamics (and your @alls) and of course how much power to overcome that big front end (still aerodynamics)
Good luck
David

Re: Cruising speed?
 

So I cant take credit for this file I just found it so use it for what it is worth.
I cheated the upload and changed it to a .pdf just remove that and it is an excel file so after you save it and rename it you should be able to run it.

Re: Cruising speed?
 

got it saved, converted, and opened. ill check it out thanks,
I also hacked the protection and unlocked the sheets as well