codrus (Forum Supporter) said:Keith Tanner said:One note on this based on my experience with the LS motors. They basically work on a gallon per hour basis. So woofling along the interstate at 75 mph means great economy (within 10% of a turbo Miata, based on a 2000 mile road trip a couple of years ago), but they're pretty tragic in stop and go traffic. The variation is far more than I've found in any other vehicle.
My Audi is like that. Twin turbo 4L V8, gets 28-ish mpg with the cruise set at 70 and less than half of that in stop and go traffic.
As for the whole "zero/infinite" thing, to be pedantic, "infinity" is not a number. N divided by 0, is not "infinity", it is "undefined". :)
Yeah, the S60R gets like 2mpg city on a cold start, 16-22 mixed, but can sail along at 30mpg all highway if I keep my foot out of it and don't use the A/C. Which is not stellar, but it is also AWD and fairly low tech: port injection, no air pump to get the cats lit off, compression ratio only slightly higher than your average flathead engine...
I did do a trip average of 24mpg cruising at 80mph... over the Appalachians and back... in 5th gear much of the way because I was towing a trailer and didn't feel good about bolting the throttle at 10 pounds of boost for minutes at a time.
The RX-7 can pretty much be relied on to need 17-20% injector duty cycle no matter if driving at 30 or 80mph. Weird efficiency island/power requirements confluence.