First, Toyota has VVTI...yes many other manufacturers now have their forms.
Second...VTEC doesn't reduce power...it saves gas mileage and increases the low end powerband (low rpm torque) by providing a low lift cam lobe...once the rpm raises and the map sensor detects the proper pressure and amount of fuel VTEC kicks in AKA...the cam lobe changes to a high-lift profile allowing more air to flow pass the valves and to the combustion chamber and provide better top end (high-rpm hp). Since the engines are small and efficient they are already great on mpg, but VTEC basically cahnges the powerband according to the factors that the ECU measures to activate VTEC. It's a take to make a small engine build more torque when it's best and more hp when it's best. Horsepower doesn't get you off the line...torque does.

 

Well said. [sm=usa.gif]
Essentially I shared the same thought in my post above but not as eloquently as you put it.

 

is vtec then essentially synonomous with a double overhead cam?

ie. do vtecs only come with DOHC? Or can it work witha complex single cam system?

 

VTEC actually only operates the intake valves...I'd say most of us with a USDM F-series or J-series engines has a SOHC...and most have VTEC also. So you don't need DOHC to have VTEC. The cam lobes you can think of as the rocker arms locking together to raise the lift. With DOHC it will lift the intake camshaft only. With SOHC cam the system is designed so that (yes their is only one camshaft that operates the intake and exhaust valves, but can use variable valve timing on the intake side.

I love good engineering, I need to GRADUATE! It's simpler than it can be explained, but more complex to understand if you are unaware of the design and how the design works.

I'd advise anyone interested in understand things check out howstuffworks.com (the automotive section) and read some books free at Barnes and Nobles. You'd be surprised at what you can teach yourself to do. Take notes to understand exactly what your engine does and when it does it. Even buy a Haynes manual from Autozone and read it. You'll learn things are easier than they appear.

 

my '05 goes 140+, and I have 300+ miles to drive today...

/drooling at work, waiting...

 

I'd take alot of tuning, parts, and labor to get my 02 (F23) to over 140+. It'd be easier to do w/ boost and proper management that'd allow the rev limiter to increase. I don't plan on going that fast...yet and if and when I do it won't be often...I like to speed through the mountains, because I can use the whole road and I can stay away from traffic.

 

I like the one way system near my university, its very twisty with starights and a variety of corners. three lanes wide!

There are also some nice hillly roads that are pretty intense- so i can understand wher 6th gen is coming from

 

Vtec is why I fell in love with hondas. If you have a vtec take your car out when it is jsut cold enough not to kick in and floor it. then floor it once vtec will engage and you will notice a HUGE difference. And I am the one that calls my accord a stock sedan beast.

 

you agree with me for a change??? well thats a start..... and soon you'll agree to anything I say : even that the Earth is a flat discus and the sun is revolvin around the earth

 

Co'Mon I knew that about the earth already...your not gonna pull a fast one on me Buddy[sm=yeahsmile.gif] WheelBrokerAng