Engine: Red Line

[JohnM15]

What is the red line of the stock standard Champion 170 CI engine? What would the top continuous cruising RPM be?

[PackardV8]

The Champion 170" develops maximum horsepower at 4,000 RPMs. There's no benefit to winding past that. It will withstand higher RPMs for occasional use, albiet more wear and tear. During my teenaged years, I shifted a still-longer stroke 185" at 4,500 RPMs in always futile efforts to make that too-small engine move the too-heavy Flight Hawk.

A highway cruise in the 3,000 - 3,500 range will get tiring on the ears, but won't damage the engine, if everything is in good nick, as they say in the Commonwealth.

jack vines

[JohnM15]

Cool, so with a 5.83 Timken in the rear and 33" Goodyears, I can drive 55 - 60 MPH...

http://studem15a-20.blogspot.com/201...pm-vs-mph.html

[jclary]

I don't have the numbers in my head like some of you guys, but...I can say with confidence (because I have done it for years) that a 185 powered C-cab truck, three speed overdrive, with the non-overdrive rear-end, will click along on flat ground at 70 mph all day long and run like it enjoys it. However, steep hills will require a well-adjusted "kickdown" switch.

[DEEPNHOCK]

You could (I wouldn't), but 45 would feel more comfortable....

Cool, so with a 5.83 Timken in the rear and 33" Goodyears, I can drive 55 - 60 MPH...

[PackardV8]

Cool, so with a 5.83 Timken in the rear and 33" Goodyears, I can drive 55 - 60 MPH..

According to the graph John attached, the RPMs would be 3,300 - 3,600 at 55 - 60 MPH. An engine in good condition will take it, but it's hard on the ears.

For years, when going on a long highway trip in my Stude truck, I would remove the engine driven cooling fan. That would lower the high RPM noise level by an amazing amount. Just don't get caught in stop-and-go traffic anywhere along the way.

jack vines