Vtec & VVTi

[teatuu]

Guys,

Can any one help me in explaining me what is the difference between Vtec & VVti.

The reason for my asking is a discussion between me and my friend. According to him VVti is derived from Vtec. Now since Vtec is owned by honda and VVTI is owned by toyota, therefore toyota pays homage(some amount in dollars) to honda for every VVTi enabled engine sold.

Is this crazy idea correct???

[s90]

This type of concept was first made by Honda thn everyone followed

[BHAILOGE]

well
Fiat was the first auto manufacturer to patent a functional variable valve timing system which included variable lift. Developed by Giovanni Torazza in the late 1960s, the system used hydraulic pressure to vary the fulcrum of the cam followers (US Patent 3,641,988). The hydraulic pressure changed according to engine speed and intake pressure. The typical opening variation was 37%.

In September 1975, General Motors patented a system intended to vary valve lift. GM was interested in throttling the intake valves in order to reduce emissions. This was done by minimizing the amount of lift at low load to keep the intake velocity higher, thereby atomizing the intake charge. GM encountered problems running at very low lift, and abandoned the project

http://en.wikipedia.org/wiki/VVT

[129]

yaar simple
honda uses VTEC
toyota uses VVTI
nissan uses CVT

( All are same )
if i ave mistaken correct me and let the professionals give there commands

[saadisb]

^^^whats CVT.

isn't it continously variable transmision

[24spins]

@129...what does CVT have to do with VTEC and VVTI??...CVT is a whole different realm...here he is asking about engines, not transmissions

[s90]

@129

yaar i think all do same work bt have different name and maybe some of them are ahead in technology frm eachother

[129]

@24spins
may be u are right but once i visited nissan lahore and the sale staff told me that Nissan Cifero is equipted with
CVT . i do asked CVT Transmission ?
His answer was " no sir CVT is Countinuous Valve Timing" that was where i was confused coz till the extent i know CVT is continuous variable transmission

May be he was wrong

[ahmadbila]

@123
no sir.it is generally taken as continous variable transmission.might b they r using it as what u hav told us.

@ALL
vtec was invented in early 1900ss...in 1910 or 1920 i dnt remember exactly.it is not invented hy honda,fiat or toyota.nd it was used to pull out water frm underground.

[aref]

Thats CVVT.
Continuous variable valve timing.

[Haceeb]

VTEC
was first system capable of changing valve timing and lift on intake and exhaust sides at the same time

[teatuu]

Guys thank you all for your feedback.... so im guessing toyota pays no homage to honda????

[teatuu]

Helllooooo?????

[bilal_khan]

vvti bolay tou
very very tharkee intellegence