Vtec?
Jeepjones85
07-21-2006, 07:47 PM
This maybe a dumb:screwy: ? But what is the purpose of the 'Vtec' and how does affect the motor?
Thanks Jeepjones85
Thanks Jeepjones85
hxgaser
07-21-2006, 08:07 PM
Welcome to the world of variable valve timing and lift and all the goodies. There are numerous websites, books an information out there, but here I try to layout a simple explaination. (Other folks are welcome to comment)
Although there are different types of VTEC, basically it changes lift of valves at different conditions. As an example, a typical vtec motor has 2 intake valves. It can be set up in such a way that only one of them opens up at lower rpm range. Or in a performance application, it can be setup so that 2 valves are opening at lower lift, and it opens more at higher rpm. Some stage 3 vtec motors such as new i-vtec, combines those 2 different conditions into a single engine.
There are other variables, such as changing intake runner route and cam timing change, and etc, but basically what vtec does is changing valve lift and/or change number of valves that are opening.
There are many sites out there explaning things in detail. Go google.
Although there are different types of VTEC, basically it changes lift of valves at different conditions. As an example, a typical vtec motor has 2 intake valves. It can be set up in such a way that only one of them opens up at lower rpm range. Or in a performance application, it can be setup so that 2 valves are opening at lower lift, and it opens more at higher rpm. Some stage 3 vtec motors such as new i-vtec, combines those 2 different conditions into a single engine.
There are other variables, such as changing intake runner route and cam timing change, and etc, but basically what vtec does is changing valve lift and/or change number of valves that are opening.
There are many sites out there explaning things in detail. Go google.
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