[Alex V.]

Firstly, these trucks were designed for *all* purposes when they were new. Some combo's aren't as ideal as others, but they didn't get to be the icon they are by being mediocre in stock form.

For a truck that isn't going to pull a whole lot, sitting on a close to stock size tire for a C10, 3.07's are good. On my Suburban with 30.5" tires that ratio is on the fast side if you want any oompf down low or much towing prowess, but with 3.07's and a 29" tire your 60 MPH RPM is only about 2,200. That puts 75 MPH up to about 2,700 which is right in a stock SBC's power curve. Many people think that speed sounds like the engine's about to come apart but it's the nature of the beast and is where these engines were designed to work best. My '82 Mercedes 5 cyl. turbodiesel turns about 2,700 @ 60 and those engines last half a million miles - most people have just gotten used to engines of more recent times that have the tech to develop a lot of low-end power so they can push vehicles along at freeway speeds at <2,000 RPM while still being able to pull hard past 4,000 RPM when the driver asks for it.

I'm used to my 1/2 ton Suburban (3.73's on 30.5 tires, 4-speed manual) and 1-ton GMC (TH400 with 4.10's and 32's), both of which turn right around 2,600-2,700 at 60, so your truck would probably feel pretty sluggish to me, but then again I don't usually sustain more than 65 MPH in mine while yours would feel a lot better up over 70.