VTEC question

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22-Aug-2002, 02:36 PM

VJ79

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VTEC question

Is a VTEC a kind of fuel management system or is it something to do i with the way the valves are programmed to function? Im not too familiar with this whole VTEC..cuz i just got into the import scene so please help anybody. What is vtec is my question. Is it a fuel management system or something different.

22-Aug-2002, 02:43 PM

ryuujin

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This belongs in the performance section

There'll be tons of people who'll give you super in depth answers to this, welcome to the board and imports

22-Aug-2002, 02:45 PM

imported_1sicsol

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Read this:
What is VTEC???

22-Aug-2002, 02:54 PM

BOND007

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Nice and too the point

22-Aug-2002, 04:26 PM

VJ79

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ok..so let me get this straight, it is a valve control system that regulates the intake stroke and exhaust stroke to give a car better performance. Optimum cam grind over the RPM range...or am i still confused here.

so could it be viewed as a fuel management system? cuz it manages the air fuel mix into the cyclinder barrel over a range or rpms

please bear with me here..im a slow learner.

22-Aug-2002, 04:53 PM

SiR-Racer

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It's not just a fuel management system. When VTEC engages the car switches to a second set of more aggressive lobes on the cams.

22-Aug-2002, 05:01 PM

VJ79

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oh..ok...so it hydraulically switches cam profiles during high revs there fore letting faster inlet of air/fuel into the compression chamber. But heres another one, it uses 2 valves for the intake stroke and two valves for the exhaust stroke. So basically it has two profiles for different rpm ranges for the two intake valves??

-am i right or just absolutely out of hope here.

22-Aug-2002, 06:05 PM

sam

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Quote:

Originally posted by VJ79
oh..ok...so it hydraulically switches cam profiles during high revs there fore letting faster inlet of air/fuel into the compression chamber. But heres another one, it uses 2 valves for the intake stroke and two valves for the exhaust stroke. So basically it has two profiles for different rpm ranges for the two intake valves??

-am i right or just absolutely out of hope here.

that's just right! on SOHC VTEC (Si), the VTEC system only controls the intake runner's timing. On DOHC VTEC (SiR), both the intake and exhaust runner timing is controlled.

someone correct me if i'm wrong

22-Aug-2002, 07:53 PM

punkindrublic

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ya thats right..... bmw made a new variable valvetrain that apparently can infinitely alter the valves within two specs.... i think they call it valvetronic....

i heard that the new k series in the integra type r in japan has cam phasing on the intake valves.... is that true??