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Old 12-30-2007, 08:55 PM   #8 (permalink)
Join Date: Dec 2007
Location: Bay Area
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The Miata - '01 Mazda MX-5 Miata
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Originally Posted by DonEaston View Post
So, not "underpowered" in the sense of "my vehicle is more powerful than yours", simply in the sense of "is it really economical to try to push a (relatively) heavy vehicle with the smallest engine possible? Would not make more sense to give a very light vehicle an engine that could essentially 'idle' down the road?"
Well, I was going to chime in before reading the entire thread... But I just checked and someone else mentioned it Higher load is the way to go for a gasser

I don't have too much experience with sub-compacts, but my father in law is an enthusiast of Geo and Kia, and when I drove them, I felt like I really had to push the things to get them to do what I wanted.
Here's a nugget to think about... Given a car's shape etc. lets say it takes 20hp to stay at speed on the highway. Weather or not your engine can make 30 or 300hp - you can only make 20hp to maintain a steady speed. So on an engine that makes less power, yes, you do need to push on the pedal a little further... But you're still going to make the same amount of power

Now think about this - the largest source of restriction in your intake is your throttle plate. If you have to keep your throttle open 30% in the smaller car versus 10% in the larger car - which one has more restriction (and therefore more pumping losses to overcome)? <-- this is a bit of an oversimplification, but a quick/easy thing to think about

For my last bit... I wouldn't call any of the modern fuel sipper ecoboxes underpowered by any means. For what they are - they're grossly overpowered (my 20hp example above really isn't too far off for cruising at highway speeds ).
Cars have not created a new problem. They merely made more urgent the necessity to solve existing ones.
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