VARIABLE VALVE TIMING
- Thread starter NYCZMP3
- Start date
D
<DooMer_Work>
I'm not sure I understand your post. The MP3s we bought in North America do NOT have variable valve timing systems (similar to Celicas, Honda's VTEC etc). A variable valve timing system will ADD power to an engine.
I do believe (correct me if I'm wrong) we have a Variable Inertial Charging System (VICS) which has two different sized intake runners to allow more air through at higher RPMS. You can notice a small boost in power around 5000 RPMs from this. I believe Variable Valve timing is still better than VICS though...
Anybody else have any ideas?
Chris
I do believe (correct me if I'm wrong) we have a Variable Inertial Charging System (VICS) which has two different sized intake runners to allow more air through at higher RPMS. You can notice a small boost in power around 5000 RPMs from this. I believe Variable Valve timing is still better than VICS though...
Anybody else have any ideas?
Chris
Honda started it, at least they released it first in the early 90's, on the NSX first, then the Integra GSR. They're the only ones I have any experience with so I'll give you what I know:
Two separate lobes on the cam, one for low RPM cruising, lower valve lift, better gas milage. Hit past 5500 RPM, switches to the other lobes, opening valves all the way, maximum output. Helps engine efficiency and gas milage if your not always hammering it, and can put more juice into it when you do. I think it adjusts timing, too, but not 100% sure on that. Seen those VTEC controllers? just allows adjustment of when the second lobes kick in, overriding factory setting of 5500 RPM.
Engines without it can do just as much HP if not more. I know plenty of Hondrossa racers around here that specifically search for non-VTEC engines to race.
Manufacturers use it mostly to keep their engines at ULEV standards and still show high peak HP numbers.
Two separate lobes on the cam, one for low RPM cruising, lower valve lift, better gas milage. Hit past 5500 RPM, switches to the other lobes, opening valves all the way, maximum output. Helps engine efficiency and gas milage if your not always hammering it, and can put more juice into it when you do. I think it adjusts timing, too, but not 100% sure on that. Seen those VTEC controllers? just allows adjustment of when the second lobes kick in, overriding factory setting of 5500 RPM.
Engines without it can do just as much HP if not more. I know plenty of Hondrossa racers around here that specifically search for non-VTEC engines to race.
Manufacturers use it mostly to keep their engines at ULEV standards and still show high peak HP numbers.
Yeah what sttl013 said. If you drive a Civic or a ITR (Integra Type R), you'll definately notice the VTEC. ITR's really come alive when they hit VTEC. The Sentra Spec V felt a bit different from the Honda VTEC. It felt like the Spec V switched to the higher lobe at WOT (wide open throttle).
