kinda a sorta. 8 per side for the initial 16 valves and then the 4 vtec rollers that lock in when the solenoid releases oil into the vtec passage. There is a small metal pin that slides when it receives oil pressure, this is what locks in the vtec part of the cam. Its complicated to think about yet very simple once you look at it and understand what is going on.

 

That is correct. Twelve roller rockers and 12 lobes. One solenoid.

 

Thanks everybody for being so helpful.

 

x4

Also:


1 & 2 are the non vtec rockers.
3 is the vtec rocker.
Note: the vtec rocker isn't a real rocker as it's not in direct contact with the valves
Only when the pins locks the 3 together it operates the valves via the other 2 rockers but it is driven by the vtec cam lobe.
There is a spring behind the pins pushing them into non-vtec position unlocking the individual rockers unless the oil pushes them the other way, locking it all into 1 big rocker.
The non vtec cam lobes are not the same btw.

So in non vtec mode the valves don't open the same hight, maybe also not the same time but that's not specified in this drawing.

 

So a solenoid located on the block, opens via oil pressure at "x" rpms. And allows oil to flow over the rockers and push the pins? I guess that is my real question. I get the pins locking onto the vtec rocker. Just don't understand how oil makes the pins engage. Sorry if I'm not being open minded enough.

 

Oil feed goes through the rocker shaft - its hollow.
Look at the cut-away of the rocker shaft of the intake valves.
(right above the spark plug)
You'll see a hole.
That is where the oil comes out and pushes the pins into the vtec position.
On all 8 rockers, 4 intake, 4 exhaust (or 8x3 = 24) at the same time.

You could - in theory - operate vtec on the intake seperately from the exhaust but you'll need 2 solenoids and a seperate oil system per rocker shaft.
IOW a totally different head design.

It would be a nice project though.
IF I had millions in the bank and a workshop to my disposal 24/7

 

Ah ok. Now it is clear. Thanks for your input. And if we all had workshops and millions in bank I wouldn't be asking that question. I'd just pay somebody to do the work for me. Lol.

 

Then you'd have 3 fuel maps and 3 timing maps lol. Might be a little tricky to tune. Especially if you add i-vtec to the mix.

 

So in this picture help how can you tell which way the pin slides? I don't have a pin infront of me but I thought they were symmetrical?

 

ChefJ Posted on Aug 11 2010, 11:34 PM
In the picture they slide from the left (non-vtec) to the right (vtec).
If you stand next to your front left wheel and look at the intake, the intake pins slide form the left to the right.
Btw.. in the blue/white cut-through picture they are in vtec mode.
The pins have the same lenght as the width of the rockers they are in.
(I hope that makes sense)
Dark blue pin is shorter than the light blue pin.
Same diameter though.



P.S.
Part #A is symmetrical (a circle).
Part #B is symmetrical (a square).
This does not mean (IMO) part #A and part #B are the same.