Elistan

Hmm. Actually, Blake got my point spot on. Perhaps I didn't express myself well enough?

wicky

I could be mistaken.... this is what I was refering to :

elistan - Take the S2000's 6th gear and make it super tall and our car's highway rating will shoot up.

cdelena - I don't think we have enough torque to allow a tall highway gear. Let the revs drop up against the heavy drag and it would not be enjoyable and the load would be tough on the engine. You just don't get the same gear choices when you have less than half the displacement.

I think chris was saying "if you gear an s2000 that tall it'll crap out" which I think is a valid point in clarifying why the s2000 isn't geared as tall as the corvette..... Maybe blake assumes this to be understood by everyone, I can't really tell.....

Elistan

I was throwing out a 100% hypothetical situation. Nobody has upped the gear ratio of 6th on an S2000, and I doubt that anybody ever will. So I'm not so much interested in why the S2000 has the 6th gear it does, what concerns me is the inescapable fact that it does have it, and what that means for our gas mileage.

So Blake is exactly correct - my point is that various other cars (like the C5) have top gears designed strictly for economy, not performance. The S2000's 6th is a performance orieted gear, however. That's all I'm saying.

wicky

I agree he got *your* point.

I think cdelena was actually explaining his take on "why". You and blake may not be interested in "why" but others such as myself and cdelena are. There is no need to be rude (blake IMO, not you) just because somebody points out "why" something is happening. The actual question at the beginning of this post is why the fuel economy is better or worse, not why do cars have 5 or 6 gears... nor why does the s2000 spin higher than other cars (to be anal )

The fact that the s2000 is performance oriented may have as much to do with the fact that it also makes very little power turning 1500. Low power isn't good for performance, and it's also not good if you can't keep the car moving. I think those are both valid points. The s2000 is geared ( i believe ) for performance. But it remains true that the engine really can't push this car at 75 mph at 1800 rpm like the corvette engine can, even if it was geared to do so.

ReDevil

I get 25mpg and theres no way I shift by 3000 every gear... more like right before 5-6 in normal driving, but each trip has to have some vtec

infinitebass

Wicky, how the hell was I rude? I merely told cdelena that he focused on the wrong thing in EListan's post.

Which, btw, is actually valid and practical. I don't see how that load would be much different than the load that is put on the engine when you are trying to redline 6th now.

Its pretty hard to redline 6th. So say you can't redline 6th currently, and say it stops at 8500 RPM's due to lack of power, and you hold steady there. You'd have to keep the throttle wide open to hold it there.

Well, with a higher gear, you'd just reach that point at a lower RPM. Still have to have the throttle wide open, except now it would be at a lower RPM. So I could be wrong, but that would mean it would be doing less work, and probably putting less stress on the engine.

But a higher 6th gear would be fine anywhere from 4k+ rpms. It might accelerate slower, but if you were to redline 5th, shift into 6th, you might fall a little below VTEC, but honestly, that would be around 130-140 MPH, and very few people cares about acceleration after that.

So I don't see how its not practical. I don't think that torque or hp would really matter. If you had a taller 6th gear, you could cruise at say, 4k rpms instead of 5k. Save gas mileage, and if you REALLY need that power then you can upshift.

So not seeing any downsides to it.

Blake

infinitebass

[QUOTE]Originally posted by wicky
[B]Wow, blake.

CoralDoc

Since EPA numbers don't always reflect reality, here is some real-world information. Before the S2000, I drove a '96 Mustang GT Convertible. I track each tank and have a lot of mileage data for both cars, 12k miles on the Ford and 43k miles on the Honda. On average, the Mustang delivered 18.8 mpg and the S2000 has delivered 24.1 mpg. On road trips (primarily highway driving at 70-75 mph) the Mustang achieved 21-22 mpg and the S2000 returned 25-26 mpg. Thats a pretty big difference in my opinion. Also, since the Honda is the faster car, I'm pretty impressed.

BTW, I agree with cdelena. We must run lower gearing to compensate for our relatively low torque F20Cs. The Mustang turned about 2500 RPM at 75 compared to around 4000 in the Honda. Power is basically torque X RPM, so each engine has to be making enough of each to keep the car moving. Adjusting the RPM by gearing so that it is closer to the torque peak allows each car to maintain velocity without a larger throttle opening that would reduce mileage. You can't cheat the laws of physics, you must get enough power to overcome wind resistance and mechanical drag and the Honda does it with lower gearing and higher RPM. Like cdelena stated, if you increase gearing to reduce RPM you will need to compensate with a larger throttle opening that may actually reduce mileage.

cdelena

[QUOTE]Originally posted by infinitebass
[B]Chris, thats not the point.

KeithD

You need to remember a Vettes MPG rating is achieved with Skip Shift, which forced a 1-4 shift unless your at WOT.