10-04-2011, 07:53 AM
|
#11 (permalink)
|
|
A True Z Fanatic
Join Date: Mar 2009
Location: Houston, TX
Posts: 4,024
Drives: too slow
Rep Power: 3595
|
Quote:
Originally Posted by WhiskeyHotel
Interesting stuff. Doesn't the VVEL vary the valve lift and duration to control power and the throttle butterfly stays wide open nearly all the time? If so, then the power varies more by VVEL rather than butterfly position.
|
I've heard that myth often, but I'm pretty sure that's not the case. VVEL very likely does vary the valve lift over different operating conditions, but that's no real substitute for actual throttle plates (which is why you still need ITBs even on the most advanced engines).
The easy way to tell is to log the throttle position over OBD-II, which is what I do on Torque while playing with this stuff. The basic Throttle Position PID comes back as angle data, and it ranges from around 1.0 to 89.6 in my testing so far. Generally speaking, if anything the throttle position has a tendency to stay more closed than you'd expect on stock-ish maps, and only opens up fully when you're at full throttle combined with high RPM.
|
|
|
Similar Threads
60Likes
Threaded Mode
