VTEC? Why?
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From: santa barbara
VTEC? Why?
Okay, call me a granny driver all you want. I want to learn and understand. I want what is best for my baby and I want to have fun.What exactly, in plain english, is VTEC?(ing?) Why do I want to do this (now that I'm passed the 600 miles). Is it bad for the car if I don't?
Just how much past 5000 rpm do I really need to go? why?
Okay...thanks for the help.
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From: Montgomery
You should probably do a search for VTEC and you will see a ton of good answers...but put simply, VTEC is the mechanism by which Honda achieves maximum power while retaining good fuel economy. In normal driving, the pistons only lift to about half of the distance they could travel, thus burning less fuel and therefore producing less acceleration. Under hard driving conditions (i.e. high RPMs) the pistons lift much higher, thereby letting more fuel into the chamber to be burned, and thus producing much more acceleration. In reality under normal driving conditions the S2k does not produce much more power than a Civic...it is only while in VTEC mode that the engine really comes to life.
Hope this helps,
Bryan
Hope this helps,
Bryan
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From: Miami, Florida
VTEC is where this car shines. I wouldn't understand why u wouldn't want to venture into VTEC land, its an amazing adrenaline rush. Not to flame, but if you don't want to venture into VTEC, then the S2000 was not the right choice. By shifting at 5000 or anywhere below VTEC, I will admit, the car is slow. However, I'm sure after a few passes into VTEC, you would constantly find yourself there. Have fun driving and enjoyt hat first time experience at VTEC, I'm sure everybody here remembers their forst time across that 6.
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From: Hayward
I didn't think VTEC had anything to do with piston travel, rather Ive read VTEC utilizes a second more aggressive cam that slips into place around 5.5-6K creating greater intake/exhaust valve lift allowing more air/fuel to enter the combustion chamber. Under 5K the engines using a cam with less aggressive lobes, effectively reducing the valve lift and air/fuel consumption.
smak
smak
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From: Toronto & FnF ssauga
Please read this, http://www.howstuffworks.com/question229.htm and don't shift from 1st to 2nd in the normal 3500RPM range.. The car is simply not made for that..
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From: Hayward
more details about general VTEC technology
http://auto.howstuffworks.com/question229.htm
S2K's use Honda's most advance VTEC engine the F20C
http://auto.howstuffworks.com/question229.htm
S2K's use Honda's most advance VTEC engine the F20C
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From: Central Massachusetts
Originally posted by smakbiam
I didn't think VTEC had anything to do with piston travel, rather Ive read VTEC utilizes a second more aggressive cam that slips into place around 5.5-6K creating greater intake/exhaust valve lift allowing more air/fuel to enter the combustion chamber. Under 5K the engines using a cam with less aggressive lobes, effectively reducing the valve lift and air/fuel consumption.
smak
I didn't think VTEC had anything to do with piston travel, rather Ive read VTEC utilizes a second more aggressive cam that slips into place around 5.5-6K creating greater intake/exhaust valve lift allowing more air/fuel to enter the combustion chamber. Under 5K the engines using a cam with less aggressive lobes, effectively reducing the valve lift and air/fuel consumption.
smak
Funny,
Your ventures into VTEC-land are your own business. Just be confident that Honda designed the engine to withstand the stresses of higher RPM operation than you'd be used to in most other engines. The engine screams when you push it to redline, and it's a blast. Don't be afraid of it.
Keep your eye on your oil level very religiously once you start VTECing... The engine isn't fully broken-in (usually) until nearly 10K miles, so expect to add a little oil frequently. As you hit higher engine RPM, the piston rings wear properly and oil is burned for a while. That tapers off (usually) in most of our engines.
Best wishes! Enjoy your car. Once you've put your foot into it, I'll be you won't want to stop!
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From: santa barbara
Originally posted by s2ksimon
and don't shift from 1st to 2nd in the normal 3500RPM range.. The car is simply not made for that..
and don't shift from 1st to 2nd in the normal 3500RPM range.. The car is simply not made for that..
I have to see when I'm shifting from 1st to 2nd. I don't really remember paying attention, I'm sure it's below the 4,000 RPM range.
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From: San Diego
there needs to be a distinction between the piston/rod and the valve/combustion chamber. The piston and rod is the large mass which reciprocates inside the block and converts the heat and compression of the combustion into useable power by pushing down on the crankshaft. the valves are mounted atop the combustion chamber in the F20C, and open to let in(intake) or expel(exhaust) the air/fuel charge. the valves are operated by camshafts, which are long rods with lobes mounted on them. the cams spin, and the lobes operate rocker arms which in turn push the valves down. the larger the lobe, the farther down the valve is pushed.
Now....
The VTEC system works by having different sets of cam profiles which are optimized for different RPM ranges. The low lift cam is good for low rpm, because it maximises torque characteristics at low revs. however, this is not a good cam profile for high RPM, where the piston is pumping far more air through it. think of the engine as a giant air pump; the more air it can pass through it, the more fuel it can burn, and the more power it can make. at the VTEC switchover point, the VTEC solenoid, which is a little electronic mechanism that controls the system, will issue the command to switch cam profiles and you will very tangibly feel and hear the difference between the low and high lift cams.
Stay below 6000 rpm before 600 miles, because the piston rings which seal the combustion chamber and prevent the expanding gas from entering the block (a condition called blow-by....=very bad.) need time to properly seat themselves in their grooves(which circumscribe the piston). given a proper break in, the rings will be properly seated and pushing against the cylinder wall to hold combustion pressure(which is dramatically increased when the VTEC system engages.) so, you want to wait to engage vtec because you dont want to put large stresses and pressures on the rings before they are properly seated; it may improperly seat them, which could have long term reliability concerns.
The reason you want to know this is that VTEC defines the very character of the car. You bought it for the shifter, the looks, the handlng, the open top; whatever. You'll love it for VTEC. make sure that you're headed in a straight line the first time you pass 6,000 in first gear...
another tip: look at a Dyno graph of a stock engine. you will be able to se the cam switch, and it's rather drastic. this will give you an idea of how the system affects the engine's output.
No it's not bad if you don't. it is bad for fuel economy, but it's such a blast that it's intoxicating and addictive; you wont mind the higher gas bills. like all cars, carbon buildup from part-throttle use is bad; equally bad is blowing to all out at once with sudden full throttle after many thousands of miles without seeing Wide open throttle. since your car is new, you wont have problems with this.
Quick2K
Now....
The VTEC system works by having different sets of cam profiles which are optimized for different RPM ranges. The low lift cam is good for low rpm, because it maximises torque characteristics at low revs. however, this is not a good cam profile for high RPM, where the piston is pumping far more air through it. think of the engine as a giant air pump; the more air it can pass through it, the more fuel it can burn, and the more power it can make. at the VTEC switchover point, the VTEC solenoid, which is a little electronic mechanism that controls the system, will issue the command to switch cam profiles and you will very tangibly feel and hear the difference between the low and high lift cams.
Stay below 6000 rpm before 600 miles, because the piston rings which seal the combustion chamber and prevent the expanding gas from entering the block (a condition called blow-by....=very bad.) need time to properly seat themselves in their grooves(which circumscribe the piston). given a proper break in, the rings will be properly seated and pushing against the cylinder wall to hold combustion pressure(which is dramatically increased when the VTEC system engages.) so, you want to wait to engage vtec because you dont want to put large stresses and pressures on the rings before they are properly seated; it may improperly seat them, which could have long term reliability concerns.
The reason you want to know this is that VTEC defines the very character of the car. You bought it for the shifter, the looks, the handlng, the open top; whatever. You'll love it for VTEC. make sure that you're headed in a straight line the first time you pass 6,000 in first gear...
another tip: look at a Dyno graph of a stock engine. you will be able to se the cam switch, and it's rather drastic. this will give you an idea of how the system affects the engine's output.
No it's not bad if you don't. it is bad for fuel economy, but it's such a blast that it's intoxicating and addictive; you wont mind the higher gas bills. like all cars, carbon buildup from part-throttle use is bad; equally bad is blowing to all out at once with sudden full throttle after many thousands of miles without seeing Wide open throttle. since your car is new, you wont have problems with this.
Quick2K
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From: VA is for hustlaz
[QUOTE]Originally posted by Quick2K
[B]there needs to be a distinction between the piston/rod and the valve/combustion chamber. The piston and rod is the large mass which reciprocates inside the block and converts the heat and compression of the combustion into useable power by pushing down on the crankshaft. the valves are mounted atop the combustion chamber in the F20C, and open to let in(intake) or expel(exhaust) the air/fuel charge. the valves are operated by camshafts, which are long rods with lobes mounted on them. the cams spin, and the lobes operate rocker arms which in turn push the valves down. the larger the lobe, the farther down the valve is pushed.
Now....
The VTEC system works by having different sets of cam profiles which are optimized for different RPM ranges. The low lift cam is good for low rpm, because it maximises torque characteristics at low revs. however, this is not a good cam profile for high RPM, where the piston is pumping far more air through it. think of the engine as a giant air pump; the more air it can pass through it, the more fuel it can burn, and the more power it can make. at the VTEC switchover point, the VTEC solenoid, which is a little electronic mechanism that controls the system, will issue the command to switch cam profiles and you will very tangibly feel and hear the difference between the low and high lift cams.
[B]there needs to be a distinction between the piston/rod and the valve/combustion chamber. The piston and rod is the large mass which reciprocates inside the block and converts the heat and compression of the combustion into useable power by pushing down on the crankshaft. the valves are mounted atop the combustion chamber in the F20C, and open to let in(intake) or expel(exhaust) the air/fuel charge. the valves are operated by camshafts, which are long rods with lobes mounted on them. the cams spin, and the lobes operate rocker arms which in turn push the valves down. the larger the lobe, the farther down the valve is pushed.
Now....
The VTEC system works by having different sets of cam profiles which are optimized for different RPM ranges. The low lift cam is good for low rpm, because it maximises torque characteristics at low revs. however, this is not a good cam profile for high RPM, where the piston is pumping far more air through it. think of the engine as a giant air pump; the more air it can pass through it, the more fuel it can burn, and the more power it can make. at the VTEC switchover point, the VTEC solenoid, which is a little electronic mechanism that controls the system, will issue the command to switch cam profiles and you will very tangibly feel and hear the difference between the low and high lift cams.