Question about VTEC

im sure you could do it in flashpro manager and i would check for you if i didnt have to boot into windows to do it :thumbsdown:

but that is a very good post webby i didnt realize the difference 10mph makes
 
I get right around 25 mpg at 180. When I go about 145 it is about 30 mpg.

Those drag coefficients are a car driving alone. Over here when you are driving at those speeds you are usually in a line of cars which cuts down on your drag. Think of it like nascar. Two cars can go faster than one.
 
webby said:
this 100%

Interesting Facts
If the national speed limit were reset to 55, it would save 1 billion barrels of oil per year.

The old national speed limit of 55 mph was created to address the energy crisis in the early 1970's - not safety purposes (although it did help safety).
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not knocking webby. he's stating fact.
I got my license right about when they lowered to 55mph . . . hated it. But now I realize that, if we lowered it to 45mph, we'd save even more oil. There's nowhere that I need to be that I can't take three or four days to get there. Let's hear it for a 45mph national speed limit! Besides, that way you get to see every leaf on every tree the whole way!:spinning:
 
M3kanic said:
I get right around 25 mpg at 180. When I go about 145 it is about 30 mpg.

Those drag coefficients are a car driving alone. Over here when you are driving at those speeds you are usually in a line of cars which cuts down on your drag. Think of it like nascar. Two cars can go faster than one.
Click to expand...

So, from your figures driving slower will net you 17% more fuel economy ~ if you have under inflated tires, that can cost you 10% on fuel economy, and alignment can also cause a loss of mileage. Tire choice can also impact fuel economy.
 
one car behind another at those speeds is called drafting isnt it ?

and not for nothing but driving at those speeds id rather my vtec be on all day and protect all my engine internals then gain a few miles on my gas meter ....:think:
speed / MPG ????? cant have one without sacrificing the other in my opinion lol

plus i cant even imagine the wear and tear on a car driving the autobahn frequently like that :bleh:
 
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plus at those speed you'd need a freakin plow attacted to the front of your car to even try to save you from 120 mph rock nicks lol .....it'll probably go right through your bumper lol
 
dont get me wrong tho i always wanted to drive the autobahn but i never thought about doing it in a civic lol ....
like renting a porcsh or lambo or even like an m5 beamer...
 
The speed limit on the autobahn is roughly 80 mph. I dont normally go over 100mph. It can be fun to drive on the Autobahn.

Renting cars like those are extremely expinsive. When I last looked into it I think it was going to cost about 2500 Euro for a GT-R and about 5000 Euro for an Aventador.

As long as you keep up with the maintenance there is not as much damage done to the newer engines of today as one would think.
 
I would think doing autobahn speeds you would lose gas mileage by turning off vtec. Even in 6th. The motor would make less power without it and have to work harder to sustain speed. Possibly causing you to be harder on the gas as well. Aside from aerodynamics at that speed you may see an increase in gas mileage with a tune and some performance mods.
 
Lol what is this infactuation with turning vtec off ?
Vtec is there to shoot more oil apon high rev / rpm to prevent premature engine breakdown so why take that chance ???
 
9thgizzyguy said:
Lol what is this infactuation with turning vtec off ?
Vtec is there to shoot more oil apon high rev / rpm to prevent premature engine breakdown so why take that chance ???
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That is not why vtec is there lol. It doesn't shoot more oil other than the oil it shoots through the camshaft to lock in the alternative lobes. Has nothing to do with keeping the engine from blowing. On a r18 vtec's alternative lobes are tuned to increase gas mileage and only engage when light on the throttle cruising. On a Si vtec's alternative lobe are high lift and duration to generate more power at high rpm's. So vtec on an Si kicks in at ~5200 rpm's. Having vtec in the Si allows honda to have a normal cam profile at low rpm that can generate torque and get decent gas mileage then switch to a "hot" cam profile designed for high rpm's to generate horsepower in that rpm range. This negates the need for a general performance camshaft robbing power at high rpm's when the engine needs to be able to breathe more to keep generating power.
 
my opolagies your right but i still cant figure why people wanna shut it off tho ????

this is what i got when i googled vtec

At the switch point a solenoid is actuated which allows (oil pressure) from a spool valve to operate a locking pin which binds the high RPM cam follower to the low RPM ones. From this point on, the valves open and close according to the high-lift profile, which opens the valve further and for a longer time. The switch-over point is variable, between a minimum and maximum point, and is determined by engine load
 
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Here that way no1 else makes the same mistake i did lol

i-VTEC
Honda i-VTEC (intelligent-VTEC)[3] has VTC continuously variable timing of camshaft phasing on the intake camshaft of DOHC VTEC engines. The technology first appeared on Honda's K-series four-cylinder engine family in 2001 (2002 in the U.S.). In the United States, the technology debuted on the 2002 Honda CR-V.
VTC controls of valve lift and valve duration are still limited to distinct low- and high-RPM profiles, but the intake camshaft is now capable of advancing between 25 and 50 degrees, depending upon engine configuration. Phasing is implemented by a computer-controlled, (oil-driven) adjustable cam sprocket. Both engine load and RPM affect VTEC. The intake phase varies from fully retarded at idle to somewhat advanced at full throttle and low RPM. The effect is further optimization of torque output, especially at low and midrange RPM. There are two types of i-VTEC K series engines which are explained in the next paragraph.
[edit] K-series

Main article: Honda K engine
The K-Series motors have two different types of i-VTEC systems implemented. The first is for the performance motors like in the RSX Type S or the Civic Si and the other is for economy motors found in the CR-V or Accord. The performance i-VTEC system is basically the same as the DOHC VTEC system of the B16A's; both intake and exhaust have 3 cam lobes per cylinder. However the valvetrain has the added benefit of roller rockers and continuously variable intake cam timing. Performance i-VTEC is a combination of conventional DOHC VTEC with VTC.
The economy i-VTEC is more like the SOHC VTEC-E in that the intake cam has only two lobes, one very small and one larger, as well as no VTEC on the exhaust cam. The two types of motor are easily distinguishable by the factory rated power output: the performance motors make around 200 hp (K20-k24z7) (150 kW) or more in stock form and the economy motors do not make much more than 160 hp (r18) (120 kW) from the factory.
 
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