PeteyBoy3K
Member
- :
- '04 Mazda3 5d, Titanium Gray
http://www.mazda6tech.com/index.php?option=content&task=view&id=14&Itemid=33
That's a link posted here earlier that describes all of the induction technologies employed on the 2.3 liter mazda engine in the mazda 6
It seems that in my 3s wagon I have VVT (variable valve timing), VTCS(variable tumble control system), and VLIM/VIS (variable length intake manifold/Variable Intake System (as mazda calls it)). It seems the 3 doesn't have a VAD (variable intake duct) which basically is a switched, loud, second intake that clicks on at a certain RPM.... those are only on the mazda 6... instead, I have an intake muffler in the wheel well combined with the VLIM that lots of people like to take off in favor of a Cold air intake.
but yea, as far as I can tell, I have a power/time line
as I rev:
at 3750, VTCS (variable tumble control system) clicks off, meaning that the small butterfly valve right before the intake chamber stops restricting airflow to make the air more turbulent and mix with fuel better. Mazda says this is for emissions and not torque.
at 4500 RPM, the VLIM (variable length intake manifold) adjusts a valve inside the manifold to maintain hemholtz resonance, and the VVT (variable valve timing) adjusts adjusts oil pressure in the intake camshaft cog... advancing the timing. Thus the timing and intake manifold length are now optimized for the higher RPM.
Thus, my general gleaning... is that this is a system that involves more parts, but not as effective (or expensive) as honda's VTEC ... which instead of using a VVT actuator on the intake cam to increase or decrease the timing... just has a camshaft that can be shifted left or right by a servo to change the cam profile (thus, actually adjusting the valve lifts in addition to timing timing). Toyota's VVT-i also uses seems special camshaft but I don't know as much about how it works.
Mazda opted to use the more sane VVT actuator in combination with VTCS to have the same effect that the variable valve lift of VTEC gives.. but the torque band is really only shifted and not as broadened as they are in VTEC engines.
But yea, finally found something describing mazda's system, squee!
Is this pretty accurate? one of the things I'm not sure about are the differences between the 6 and the 3. It seems like in the 3, there is some "box" in the wheel well that acts as the VLIM and an intake muffler (which most people talk about removing for more horsepower). It also seems like the 3 doesn't have the VAD on the airbox.
That's a link posted here earlier that describes all of the induction technologies employed on the 2.3 liter mazda engine in the mazda 6
It seems that in my 3s wagon I have VVT (variable valve timing), VTCS(variable tumble control system), and VLIM/VIS (variable length intake manifold/Variable Intake System (as mazda calls it)). It seems the 3 doesn't have a VAD (variable intake duct) which basically is a switched, loud, second intake that clicks on at a certain RPM.... those are only on the mazda 6... instead, I have an intake muffler in the wheel well combined with the VLIM that lots of people like to take off in favor of a Cold air intake.
but yea, as far as I can tell, I have a power/time line
as I rev:
at 3750, VTCS (variable tumble control system) clicks off, meaning that the small butterfly valve right before the intake chamber stops restricting airflow to make the air more turbulent and mix with fuel better. Mazda says this is for emissions and not torque.
at 4500 RPM, the VLIM (variable length intake manifold) adjusts a valve inside the manifold to maintain hemholtz resonance, and the VVT (variable valve timing) adjusts adjusts oil pressure in the intake camshaft cog... advancing the timing. Thus the timing and intake manifold length are now optimized for the higher RPM.
Thus, my general gleaning... is that this is a system that involves more parts, but not as effective (or expensive) as honda's VTEC ... which instead of using a VVT actuator on the intake cam to increase or decrease the timing... just has a camshaft that can be shifted left or right by a servo to change the cam profile (thus, actually adjusting the valve lifts in addition to timing timing). Toyota's VVT-i also uses seems special camshaft but I don't know as much about how it works.
Mazda opted to use the more sane VVT actuator in combination with VTCS to have the same effect that the variable valve lift of VTEC gives.. but the torque band is really only shifted and not as broadened as they are in VTEC engines.
But yea, finally found something describing mazda's system, squee!
Is this pretty accurate? one of the things I'm not sure about are the differences between the 6 and the 3. It seems like in the 3, there is some "box" in the wheel well that acts as the VLIM and an intake muffler (which most people talk about removing for more horsepower). It also seems like the 3 doesn't have the VAD on the airbox.