Quote:
Originally Posted by Christ
adding to that -
Vtec isn't actually a separate cam profile... the cam has an extra lobe between the standard lobes, that is always riding on a rocker arm.
When Vtec engages, the solenoid fires up and it moves a lever in the head which engages the rocker that is riding on the larger cam lobe.
The cam doesnt shift positions, nothing of the sort happens.
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well it IS a seperate cam profile, or there would be no point, its a different cam profile on a lobe between the two standard lobes, which as you say rides on a trailing arm that is seperate from the trailing arms which acuate the valves (which the standard cam lobes ride on). the vtec solinoid allows oil pressure to push a pin through the trailing arms to connect them all as one, riding on the big lobe.
the economy version does similar stuff but with only 2 cams per cyl, one arm and valve rides on the big lobe, one on the small lobe, then the vtec solinoid allows oil pressure to push a pin out and lock them together so they ride on the big cam. is that how I wrote it before? sorry if it got confusing.
though, this is for the Kseries, so the fits and Si's and all 4cyl acuras do this, as well as 4cyl accords and crv's and the element. the accords, base RSX, crv, element, 2002-2005 Si and I belive the fit all run off the "2lobe vtec" whereas the 06+Si, TSX, RSX-s, and some of the sportier accords run the "3lobe vtec" ("true vtec")
after reading about the "lean burn" civics this 2 lobe system looks to do the same thing, only I dont think we are seeing af ratios over 14:1 come stock. again, out comes the laptop and hook into your programmable ECU and lean that baby out a little, run a test and check for detonation, try a little more..... anyone wanna give me one of these units to test out the eco benefits of a fully tunable 2.0 engine?