This VTEC thing

[Redrook]

Ok, pretty noob question here. Did a search but didn't really help. So I understand the basics of what VTEC is though not entirely sure why it's useful. I do see that it enables the middle rocker arm automatically at a certain rpm (4500?).

My question is what does this mean for me? I have a 1.8i vtec s 6th gen. Does it just mean more power at a higher rpm?

I have read about some type Rs where you can manually set vtech kick in points and things like that but I don't think any of it applies to my car. I have noticed that when going at 70mph I am doing around 3500 rpm, which I think is a bit high but figured that's because it's an older car from when people didn't care about economy. Is this related? Can someone enlighten me about my vtech?

 

[Roylewaa]

http://www.youtube.com/watch?v=AcT_ZyY3F0k

It not massively noticible on the 1.8 and the 2.0 however stick a induction kit on and boy will you hear it
it sounds amazing



I have one of these fitted to mine and I recently fitted one to my mates 1.8, I found VTEC kicks in a little earlier on the 1.8 for some reason, just under 4k, on mine its 4500k

http://www.ebay.co.uk/itm/190601363115?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Cheap and fits in under 10 minutes

 

[BlueVTEC]

The camshaft in the F18/F20 SOHC VTEC has two lobe profiles instead of the usual one, and with each lobe there is a "rocker" shaft. Below 4500rpm (ish!) the car is on the economy mode, so is only using one rocker while the other one is doing nothing.

Above 4500rpm at W.O.T (wide open throttle), VTEC engages. The car knows to engage VTEC by reading the oil pressure, air intake volume and air intake pressure. It then sends a signal to the VTEC solenoid, which then engages the second rocker. When this happens, BOTH rockers are now moving in sync, however it has now switched to the VTEC cam. The VTEC cam has a much larger lobe, which in basic terms means the intake and exhaust valves are held open for longer, meaning the car can throw more air and fuel into the engine creating a bigger bang. The bigger the bang, the more power you get!...To an extent.

As for the kick....Well, SOHC VTECs are primarily an economy engine and aren't exactly performance orientated. Despite this, you should notice an increased eagerness for the car to rev, and it should pull harder the more you rev, especially in the 2.0 and 2.3 models. DOHCs however are totally different. Whereas SOHCS have good low range torque with a slight surge of power when engaging VTEC, DOHCs have nothing below VTEC but go mental above it! My H22A7 (Type-R engine) is fairly average in the bottom end, but hit 5800rpm and it just shifts!

Hope that helps anyway. There are lots of videos on YouTube covering it, with some using the American F22/3 SOHC VTEC as the demonstration, which primarily is the same engine as the english F18/20/23.



P.S I should clarify, while VTEC is engaged and both rockers are moving, the rocker for the economy lobe is NOT in contact with the cam despite moving with the VTEC rocker. It doesn't contact because the economy rocker is following the direction of the VTEC rocker, which as said above is working on a cam that has a much larger profile. I hope that makes sense!

 

[Redrook]

Thanks guys, all clear to me now. Don't often get it up to those revs (I try to drive economically usually) but this may change now haha.

 

[Roylewaa]

Thanks guys, all clear to me now. Don't often get it up to those revs (I try to drive economically usually) but this may change now haha.

It will if you fitted an induction kit :lol:
I never went past 4k before I fitted one

 

[BlueVTEC]

It will if you fitted an induction kit :lol:
I never went past 4k before I fitted one

Either that or he could remove the silencer from the OEM airbox. I've done that to all my Accords and it gives them a real throaty roar!

 

[mikem]

http://www.youtube.com/watch?v=AcT_ZyY3F0k

It not massively noticible on the 1.8 and the 2.0 however stick a induction kit on and boy will you hear it
it sounds amazing



I have one of these fitted to mine and I recently fitted one to my mates 1.8, I found VTEC kicks in a little earlier on the 1.8 for some reason, just under 4k, on mine its 4500k

http://www.ebay.co.uk/itm/190601363115?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Cheap and fits in under 10 minutes

Does it really do anything other than make a noise? :wacko:
Does it improve economy?
Should you tell your insurer? :blink:

 

[Roylewaa]

It's supposed to add 5-10 hp but that is debatable, so yes more for the noise

Economy is supposed to be the same, however like me you will notice you will be putting more fuel in as you might find you drive the car harder

Yes you should tell your insurer

 

[BlueVTEC]

It's supposed to add 5-10 hp but that is debatable, so yes more for the noise

Economy is supposed to be the same, however like me you will notice you will be putting more fuel in as you might find you drive the car harder

Yes you should tell your insurer

You could just take the silencer off. It's a free mod, and you wouldn't have to tell your insurer.

"Whats a silencer?"

 

[Stevearcade]

Take off the resonator on the air inlet and if you want to make more noise, add some cold air feeds into your stock air box with some wide, flexible piping if you want more cold air. Getting cold air into the engine can be done effectively and for very little. I went the Cold Air Intake with the filter down behind the bumper as I bought into the idea of the open element filter giving more power. Does it, I don't know, I think there's a placebo effect from the noise. If it does increase power, it's not enough to really notice I don't think. But it does change the characteristic of the car, in terms of throttle feel and noise, which together make for a much more engaging driving experience. I would recommend some sort of modification on air intake if you enjoy your driving.

 

[BlueVTEC]

Take off the resonator on the air inlet and if you want to make more noise, add some cold air feeds into your stock air box with some wide, flexible piping if you want more cold air. Getting cold air into the engine can be done effectively and for very little. I went the Cold Air Intake with the filter down behind the bumper as I bought into the idea of the open element filter giving more power. Does it, I don't know, I think there's a placebo effect from the noise. If it does increase power, it's not enough to really notice I don't think. But it does change the characteristic of the car, in terms of throttle feel and noise, which together make for a much more engaging driving experience. I would recommend some sort of modification on air intake if you enjoy your driving.

All good tips!

One thing I would just add. The silencer has a fail-safe inside which stops the engine sucking up water. When water is sucked in via the inlet pipe, it fills the silencer chamber with water causing a large rubber flap to lift, blocking the inlet and cutting out the engine, thus stopping any water from being sucked in.

Naturally you will be making this redundant as you will be removing the whole system....Worth bearing that in mind before splashing through puddles.

 

[Stevearcade]

Totally. I'm very conscious of puddles, but having driven a year with a CAI all's well. It wasn't an issue on my MOT today (in fact none of my modifications were - just some old normal parts ).

 

[BlueVTEC]

Totally. I'm very conscious of puddles, but having driven a year with a CAI all's well. It wasn't an issue on my MOT today (in fact none of my modifications were - just some old normal parts ).

One thing I hate about 6th gens (both F & H-seriesmodels) is the crank pulley location. Not only is it very close to the nearside wheel, there is nothing protecting it from debris or water! Even when avoiding puddles (which I always do ), it still causes the auxillary belt to squeal if the rain is heavy enough!

I really should get around to making a guard or some sort of cover for it...

 

[Yadash]

How might one go about removing this silencer?

 

[accord2001]

Thanks guys, all clear to me now. Don't often get it up to those revs (I try to drive economically usually) but this may change now haha.

Welcome to the forum mate! you will be amazed how knowledgeable the members are!!!!!!

Hope u enjoy ur CG8 which i did!

In simple terms for me to get more out of the Vtec engine, Just drop one gear and she goessss!!!!!!!

 

[jjmartin349571]

How might one go about removing this silencer?

Take the front bumper off, and the resonator is a big black plastic box below the wing on the offside. It just unbolts from the body of the car from memory. I removed mine after I fitted my induction kit as it was just uneccasary weight, and once it was removed there was space for a cold air feed to the front grille

 

[Asim]

^ Thank you very much haha been looking at that big heavy plastic piece of $#1t for days wondering what to do lol

 

[KyleF18Martin]

http://www.youtube.com/watch?v=AcT_ZyY3F0k

It not massively noticible on the 1.8 and the 2.0 however stick a induction kit on and boy will you hear it
it sounds amazing




I have one of these fitted to mine and I recently fitted one to my mates 1.8, I found VTEC kicks in a little earlier on the 1.8 for some reason, just under 4k, on mine its 4500k

http://www.ebay.co.uk/itm/190601363115?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Cheap and fits in under 10 minutes

Ive been looking for a proper induction kit for weeks now! and all i have been able to find are kits for the H22 engine, many thanks!