Author Topic: Finally on  (Read 7568 times)

Offline JohnnyPopper

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Re: Finally on
« Reply #30 on: May 22, 2021, 10:24:07 PM »
Wow, forgot the 55 mph mandate from the phony...

So VZ, the average speed today on freeways is 70-80, (unless you factor in complete idiots and motorcyle organ donors) What is the Best? RPM in that range regarding fuel efficiency?

I expect there are other factor I am not including... :(

Given the immediate future of the economy/ policy it would be good to know...as futile as it sounds.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: Finally on
« Reply #31 on: May 23, 2021, 06:47:37 AM »
If I'm not doing 85 MPH on the way to work, I'm being tailgated. The average morning commute speed around here is 80-100 MPH on the highway.

The best RPM would be the lowest possible with the ability to maintain the speed you desire in order to get the best fuel efficiency.

Take my 74 for example. Desired final drive ratio is 3.73:1 but on the highway at 80 MPH I'd be at over 3600RPM with a TH400. With a 4L80E I'd drop over 1000 RPM without sacrificing anything. Anyway, a bit of thread hi-jacking here  8)
,                           ___ 
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              ⌠ŻŻŻŻŻ'   [☼===☼]
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: Finally on
« Reply #32 on: May 23, 2021, 02:09:23 PM »
LOL it's amazing how things have changed from when I first started driving-LE everywhere, now nowhere to be seen...sad.

Engine a 350? That puts you in 2500-2700 RPM range, where max torque lives.

Always thought that was the sweet spot/desired range when it comes to changes in elevation.

Okay Shifty, it's all yours again! Thanks for the space! 
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction