completely random crap

I was always a motor head. Some of u might know that as well. According to some sources, I've been a motor head since i was a few years old. Those days, the Motor GP and Michael Schumacher's reign in F1 was at its peak. This is something i can't remember though. but heck who cares. i have Nitrous Oxide in my blood. hehe. Something i came across on the internet. Vtec VS VVTi VS iDSI. As usual read lor... see what's its about. I roughly know that vtec from honda and vvti from toyota(was co-developed with Yamaha if i remember correctly) involves the timing of the valves. You see, a normally aspirated engine are able to produce power easily at lower rpm. But when the engine is revved at higher rpms, the air going into the engine is not enough compared to lower speeds. Therefore they came out with valve timing lift and control(something like that). Its a tech which involves increasing the time of the intake valve's opening. By increasing the intake time... more air will be able to enter to the combustion chamber thus making more power.



This is a sample pic of the lobes on the camshaft. u see normal engines example is on the left while a vtec(or a similarly vvti) on the right. can u see the difference? a vtec has an extra lobe that create another cam profile that give it the extra lifting required to achieve higher power. VVTi runs on a similar concept as the Vtec. So i guess its not necessary to talk bout it. The new generation of Honda's are now using i-Vtec which is the lastest generation of Honda's Vtec. It doesn't have the distinctive sound when the higher profile is selected. Engine suchs as the Honda B16B are very famous among our local racers.

meanwhile. the iDSI are Honda's way of creating a more fuel efficient engine by placing 2 spark plugs in the combustion chamber(i am not really sure where it is situated but should be roughly there). The first plug will ignite first burning the fuel. Then the second plug will ignite to burn any excess fuel that are not burned properly earlier on in te first ignition. This create a higher efficiency engine though a slightly higher maintenance due to the 2 spark plugs per cylinder(8 plugs in total). Thats why the iDSI honda Jazz and City are very economical.



Well i guess thats it... hehe