Vtec Problem...

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Originally Posted by Shraka

It is. You can hear it when you run it on the dyno. It sounds quite moderate up to 5800rpm, then you get the VTEC swap onto high cam, and it suddenly gets a deep voice.

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Incorrect

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Originally Posted by VTec1987

Been covered so many tym with integra vtir motors with dual stage IM
Vtec comes first then secondary butterflies, u can hear it better at 5800 doesnt mean its vtec.

Y dun you hook up a light bulb to ur vtec switch and see when vtec kicks in

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Correct
Big cam @4400rpm
Secondary Butterflies@5800 (shorter inlet hence more noise)

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Originally Posted by Webby_roller

Hey, i will have to do some searching at a mates house, but he has a h22a vtir, and the dyno sheet looks similair to yours.

The vtec comes on first, then secondaries come on second, the reason there is a greater increase at the point of the second switching point is that there is more air getting into the intake manifold, more air, more power....

more open area in the intake manifold, the less resistance for the air to flow through, the more power it will make....

Plus there are alot of respectable websites that show stats for honda motors and the vtec in a vtir is 4500, and secondaries at 5800....

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Could you link some of them up please so I can take a look?

As I said, Toyota has TVIS, which operates in exactly the same way as VVIS. In the 4A-GEs I've driven, it is totally progressive, and doesn't give the aggressive change in torque seen at 5800rpm in my VTiRs dyno graph. It feels much more like the slight improvement in breathing my car gets at around 4000rpm, which is so much most subtle than the change at 5800.

I really think that VTEC is coming on at ~5800 in my VTiR. The change in engine note and torque profile is just too aggressive to be VVIS in my opinion.

If you listen very carefully you can hear a change in note at 4400, it's just well muffled by the long primary inlet.

http://i17.photobucket.com/albums/b5...ec_diagram.jpg

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Originally Posted by T-onedc2

If you listen very carefully you can hear a change in note at 4400, it's just well muffled by the long primary inlet.

http://i17.photobucket.com/albums/b5...ec_diagram.jpg

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Well blow me down. I could have sworn I've read 1,000 times that it comes on at 6800. I guess I must be mad or something.

hey got another problem, i bought the intake pipe for my vtir, when i put it on i cant hear the vtec kicking in, when i put the stock intake pipe, then i can hear it...does anyone know y???

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Originally Posted by Shraka

Well blow me down. I could have sworn I've read 1,000 times that it comes on at 6800. I guess I must be mad or something.

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gag, gag, gag

;););)

what the hell is an intake pipe?

if you're more specific, maybe we can explain for you.

usually, the shorter and more direct the intake duct from where the filter sucks in fresh air to the intake manifold, themore noise you will hear.

maybe with your new intake piep, you're making the flow of air, less direct and therefore would make the noise more muffled.

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Originally Posted by Rehaan Khan

hey got another problem, i bought the intake pipe for my vtir, when i put it on i cant hear the vtec kicking in, when i put the stock intake pipe, then i can hear it...does anyone know y???

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Another common problem is the thermostat gets stuck and the engine never warms up, which in turn won't allow vtec engagement. Is your car always running cool?

nah my engines runs cool

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Originally Posted by Rehaan Khan

nah my engines runs cool

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Not necessarily a good thing, look here:
http://www.ozhonda.com/forum/showthread.php?t=8692

yeh i read that b4...but mine is normal....the temperature doesnt drop once u go faster...

take ur noise resonator off, if u have stock exhaust u should be able to hear it. VTi-R has more smooth transition due to the intake manifold unlike b16 or ITR. If your gaining more power after 5k then you have vtec, if you are not gaining or losing then ur vtec fell off