help with my noob questions

WS6isKing · 08-26-2006

I have 2 pretty basic questions that have beeen bugging me all day at work (yeah my mind has plenty of time to stray.)

Ok, I know I'm lost when it comes to VVT- so bear with my stupid questions. First I was jsut wondering what rpms the VVT engages at.

But the stupid question is - is the third valve per cylinder an intake or exhaust valve? I was thinking exhaust- but then I wondered if the second intake valve was for VVT. please help me understand this.

twgonder · 08-26-2006

Both good questions! I have lots more like that when it comes to all the computer stuff. If Ford has published information on these things, it sure would be nice to read. The sales brochure and owner's manual are pretty weak. Anyone got ideas on where (and if) Ford shares this stuff with their customers?

In the old days, we just took it apart to see how it worked. Not so easy these days. I can't believe Ford has any real trade secrets that Japan and Germany don't already know.

mustanghelper · 08-26-2006

2 smaller valves will flow more air than 1 valve .

MD07GT · 08-26-2006

The third valve is an intake valve.

**stlwagon** · 08-26-2006

Quote:

Originally Posted by MD07GT

The third valve is an intake valve.

Edit: correct. 2 intake and 1 exhaust valve per cylinder..

WS6isKing · 08-26-2006

is it always opening and closing or just opening during VVT? Sorry, I don't really understand a whole lot abou this.

And I just thought of another question- Is the S197 still a SOHC? I saw the sales brochure too, my friend was thinking of getting one. Those things are always meant for the layman, and the layman really doesn't care how many valves it has or what VVT is.

Hell, many Mustang drivers don't even know what their car can do in the 1/4. But I'm not bashing- it's the same way with almost every car- including mine.

**stlwagon** · 08-26-2006

Quote:

Originally Posted by WS6isKing

is it always opening and closing or just opening during VVT? Sorry, I don't really understand a whole lot abou this.

And I just thought of another question- Is the S197 still a SOHC? I saw the sales brochure too, my friend was thinking of getting one. Those things are always meant for the layman, and the layman really doesn't care how many valves it has or what VVT is.

Hell, many Mustang drivers don't even know what their car can do in the 1/4. But I'm not bashing- it's the same way with almost every car- including mine.

It is a SOHC. With VVT, a sensor is used to detect the engine's speed. An electronic system then uses the information to adjust the valve opening and closing timings accordingly. This allows for maximum torque at all engine speeds.

WS6isKing · 08-26-2006

Quote:

Originally Posted by stlwagon

It is a SOHC. With VVT, a sensor is used to detect the engine's speed. An electronic system then uses the information to adjust the valve opening and closing timings accordingly. This allows for maximum torque at all engine speeds.

Ok, so theres still only one cam for the intake valves and exhasut valves for each straight 4. So it's not quite like VTEC for Hondas then, I think with VTEC there is a completely different cam that is only used above a certain rpm range.

Sorry if my questions are bothering anyone, but I jsut love to understand how things work. Future engineer.

BatFink · 08-26-2006

Quote:

Originally Posted by stlwagon

Edit: correct. 2 intake and 1 exhaust valve per cylinder..

So it's a 3V per cyl 24V whole engine?

**stlwagon** · 08-26-2006

Quote:

Originally Posted by BatFink

So it's a 3V per cyl 24V whole engine?

That is correct... vs the 2v (16) on the older 4.6 and the 4v (32) on the last generation Cobra.

WS6isKing · 08-27-2006

Quote:

Originally Posted by stlwagon

That is correct... vs the 2v (16) on the older 4.6 and the 4v (32) on the last generation Cobra.

Don't forget the Mach 1

99vert · 08-28-2006

Don't forget the Charge Motion Runner Controls. They control airflow to the second intake valve on each cylinder.

pfiandra · 08-28-2006

Correct if I'm wrong but VVT really isn't changing the actual timing of the intake valves but it is changing intake valves lift. From what understand there is a hydraulically operated pin or pusher on the top of the lifter that is triggered at around 3000 RPM that causes the valve to open further at the high end of the cam lobe. This enables much better low end torque performance at low RPM's and better high end torque performance at high RPM's. It's the best of both worlds. I think I got that right. By the way, from what I have read, Mercedes invented that three valve system and use it in all their high performance cars.