11-08-2005, 01:43 PM
Evan Wrote:gearing and drag. cruising on the highway you are over 4k rpm.
the engines are also relatively low compression, so they arent as efficient, and use a pretty agressive cam to get power
30mpg isnt horrible anyway. Better than my 240
ok, the 4k could be much of it. Although I bet the '06 doesn't turn that much. And the drag coefficient is pretty high at .38 on the earlier Miatas (which is actually higher than what I've found for E30's-- that's disgusting). Maybe that's all it takes to explain the earlier Miata's poor economy. But from what I can find out, the first gens were about 9:1 (pretty normal for early 90's), up to 9.5:1 later, and now 10.8:1 in the '06. And the drag coefficient has dropped slightly to .37 from what I can find. With no improvement in economy.
So on the '06, we've got variable valve timing, slightly lower drag, lower hwy RPMs, much higher compression ratio. Why didn't economy go up. :?: