Just a quick question
Prowlin' with a Purpose
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Re: Just a quick question
umm depends on the engine.. honda has like 4 or so variants of vtec and i-vtec
vtec-sohc usually intake only 3 cam lobe profiles 2 low rpm lobes and 1 high rpm lobes, just for efficiency
vtec-e - sohc, intake only, 2 cam lobes, 1 idle valve, 1 open valve, til the vtec engages, then both valves open
dohc vtec, 3 cam lobes just like above, but expanded to the exhaust cam, usually higher output engines
dohc i-vtec-e, vtec-e with a dedicated exhaust camshaft.. added intake advance/retard feature which can create a good powerband
dohc i-vtec, same as dohc vtec, with advance/retard intake cam, power at any rpm...
i-vtec vcm, variable cylinder managment, only found on hybrids and v6 models, the v6 shuts off the front cylinders and runs on the rear 3 cylinders, this is done by deactivating the valves on the front head
i-vtec vcm II, same as above but adds 6 4 and 3 cylinder operation, improves gas mileage and power slightly, some variants of this have a variable runner intake manifold, but again, it depends on the model
vtec-sohc usually intake only 3 cam lobe profiles 2 low rpm lobes and 1 high rpm lobes, just for efficiency
vtec-e - sohc, intake only, 2 cam lobes, 1 idle valve, 1 open valve, til the vtec engages, then both valves open
dohc vtec, 3 cam lobes just like above, but expanded to the exhaust cam, usually higher output engines
dohc i-vtec-e, vtec-e with a dedicated exhaust camshaft.. added intake advance/retard feature which can create a good powerband
dohc i-vtec, same as dohc vtec, with advance/retard intake cam, power at any rpm...
i-vtec vcm, variable cylinder managment, only found on hybrids and v6 models, the v6 shuts off the front cylinders and runs on the rear 3 cylinders, this is done by deactivating the valves on the front head
i-vtec vcm II, same as above but adds 6 4 and 3 cylinder operation, improves gas mileage and power slightly, some variants of this have a variable runner intake manifold, but again, it depends on the model
Last edited by WannaBFast; Nov 11, 2008 at 12:23 AM.
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