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I know this kind of thing has been covered may times before.....

When I am going down the highway at about 80 or so, the RPMs are real high. Higher than I want them to be anyhow, but Im usually in a hurry so I dont slow down to lower them. Is this wasting gas, or is it just kinda normal amount of gas usuage to be going at that speed for 20+min?

 
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You're better off doin 80 on the highway than being in constant stop n go traffic, especially for conserving gas...If you have a 5-speed then doin 80mph in 5th gear is good..If ur still in 4th doin 80mph then u got high rpms...If thats the case use that 5th gear. Thats why we have it.

 
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I get 32-33 mph going 80 all the time. I don't think I'm wasting any gas at all.

 
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going at 65 or 75 will definitely give u better mpg results than going at 80.

but a constant speed is better than stop and go, or frequent change of speed.

although there's a point where u're simply using a lot of gas. i believe 90+

or... when u''re constantly in vtec..

ie: I drove for like 15 min. at 110 mph +

needless to say it ate up quite a bit of gas. probably 2-5 gallons gone right there.

I noticed I've been using so much gas lately.. so even though I want to get home fast, I sometimes drive at 70 or so.. keeping the rpm below 3500 to save gas.

lol. sad.

 
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whenever i think that i am waisting gas i just think about how bad it must suck to be driving a escalade.12-16 mpg. haha

 
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think of theose H2's those things chuck the petro lol

 
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sometimes to save my gas I only do like 50-52 casue then in 5th the RPMs are only at 2.5 - then in town I try to keep it at 2 in 5th, wich is about 41-43

 
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to save gas i shift anywhere between 1.5k-2k... it takes forever and people behind me get mad sometimes but i don't care....

5th gear at 30mph

doing that i get 40+ mpg on my hx

 
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Aren't you always in Vtec over like 60 mph or so. I know thats when mine kicks in cause thats when I see a little blue light in my dash....

 
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also, i thought v-tec makes the engine more gas efficient? i dunno, i thought i heard that somewhere... could be wrong

 
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yes, someone answer those questions....

 
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vtec works like this: when the ECU hits a preset limit, it activates the vtec, which basically sticks a little pin in all your valves. This pin is connected to another valve, which is higher than your normal valves. On the SOHC vtec, this means that all your valves (intake and exhaust) are open longer in vtec. This is good at higher rpms, because you need them open for more power. At lower rpm's, however, the vtec deactivates, because you would have a very rought idle with that much valve overlap (intake valve open at the same time exhaust is). When people say the vtec saves gas, they mean that while the vtec isn't activated, you have very good gas mileage on your vtec 127-hp car as compared to someone who has a 127-non vtec car because the vtec gives you more HP on the high end. Hope that answered some of your questions. I have "the honda performance builder's handbook", and theres an entire chapter on vtec. In a word, the DOHC vtec, when vtec is activates, uses an entirely different cam lobe profile (given my the second camshaft). Therefore, it is better than SOHC. And i-vtec is even better. I don't know how it works, but ideally all engines should constantly be changing cam lobe profiles as they change RPMs. vtec is close, DOHC vtec is even closer, i-vtec closer still.

 
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sounds like you are on the virge of answering... now Im confused... you do seem to know about vtec tho....

 
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haha sorry. I found a website on it a while ago, I'll try to find that again. It had pictures and everything. Much more helpful than my gibberish

 
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got it : http://www.leecao.com/honda/vtec/whatsvtec.html

That site also has specifics on SOHC vtec, DOHC vtec, vtec-e and 3-stage v-tec (i-vtec?) Hope this helps.

 
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I thought that our year Vtec (7th gens are different I heard) it is just more gas being put into the engine......but I have no clue if that is correct...

 
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about the orgininal topic of the post..

if your in ur highest gear, driving at the lowest rpm then typically you loose the least with the highest speed..

so if you go 30mph in 3rd you use more gas then if you were in 5th...

on the highway tho... i dont like going slow so im in 5th going 90...so thats like 3,500rpm? i dont care... i get good milage

 
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as a general rule, cars get their best gas efficiency at around 35mph. So the faster you go above that, or the slower you go, the worse mpg's you get. That's just the ratio of time and your wind resistance. Anyway, Connie, did you go to the link i provided? Evidently not. It sort of lets more gas into the engine...but only because it lets more air too.

 
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so if I keep the RPMs real low when going 25 Im using more gas than i would when going 35??? that makes no sense. also, lets say for example going 35 in 3rd is 3.5 RPMs, so if Im in 5th and doing 50 at 2.5, then Im using more gas???

I want to understand what you are saying

 
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so, and when you say it most efficient to go 35mph, does that mean in 1st gear redlining? or in 3rd or 5th gear?--------just pointing that out because it didnt make complete sense.


-KG

ps: i dont mean to mention vtec now, but i do get the point that WHEN engaged causes a higher gas consumption, so there is no point in having it engaged and trying to get the best gas efficiency in your car.

 
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i think the relevancy of vtec is that while a 127-hp honda vtec has the same HP as some other car, that peak HP is used by the high-lobe profile. THerefore, at lower RPM's, a vtec car has better gas efficiency than that other car. And yes, I was addressing Connie, not you. Sorry for the confusion. And by 35mph, I think that it's just the generic limit...nothing specific. Any faster than that, and you're wasting gas fighting air...any slower than that, and the energy required to keep the engine running is a large ratio. I think that the lower the RMPs, at whatever speed, the better the gas mileage, so 5th.

 
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i think saying that it is simply a generic limit doesnt do it for me.

i am not arguing that, because i can be in 5th crusing at 35mph and get great milage...but then the gear should be stated in conjunction with the mph

 
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this is getting confusing