VTEC = I can't remember exactly what it stands for...

but basically it is a Variable Valve Timing which is Electronically Controlled.


When running in low RPM's and midrange you will run a basic camshaft, however, when VTEC kicks in (when the computer decides to) the Valve Train basically rotates to allow better intake/exhuast flow at High RPM's.

Nissan also has their own VTEC called VVTi. Variable Valve Timing.

 

your right about variable valve timing but your also wrong. on Dohc engines they have a 3rd lobe in between both lobes for the intake valves. when you raise your RPM's you raise oil pressure which moves a solenoid up by building pressure. the third lobe is a little bit longer than the other two which when pushes down keeps the intake valves open a little longer than usual allowing more air into the air/fuel mix. thus v tec is happening

 

all you wanted to know about VTEC

if the link works anyway.

 

i thought it was toyota that had vvti? well dont let any one tell you vtec dosent really do anything. alot of my friends are into hondas and when the cars (not stock) cross over into vtec you can feel it i mean it is a noticeable differenc and its gets louder and sounds like fart cannon. the only way a honda sounds good is with a stock muffler so you cant hear it

 

It will cause problems when trying to get more power out of the motor. You have to really know what you are doing when you start adding extreme amounts of boost. I learned this the hard way with my 1996 Civic.

 

"On Nissans Varable Valve Timing retards the exhuast cam."

This is how it was explained to me. Honda Vtec does the same thing a different way.

Ray

 

Nissans is called "NEO VVL", but its not variable valve timming it's variable valve lift. Nissans variable valve timming comes on several Nissan models including the 350Z and 300ZX, they just dont advertise or hype it like another company I wont mention

I dont think Nissan has any Neo VVL in the US, in Japan they have a 1.6L SR engine with VVL in a special eddtion pulsar(N-1 I think) the engine is called an SR16VE and it made 200hp NA. Thats equal to the S2000's hp/l that ricers seem to drool over for some reason.

 

WRONG!

SR16VR: Nissan's high winding 1.6 liter, 175-hp four cylinder, essentially a destroked sr20 with Nissan's version of VTEC called VVL. Found in overseas Pulsars.

Defination provided by Sport Compact Car, you can visit them on online at www.sportcompactcarweb.com

 

vvti is toyota

 

i read the howstuffworks site about VTEC, and I now understand how it works, but I can't help but wonder...

When these cars are driving around with 200,000+ miles on them, are they going to suffer from stuck pins and have some cylinders stuck with the high or low RPM cam profile while the other cylinders are still functioning normally? Will repetitive stresses ever lead to pin breakage? Is wear of the pins significant enough to cause looseness in the valvetrain?

Does anyone have a link to a site telling the exact workings of Nissans, system, Toyotas VVTi and VVTLi, and BMWs VANOS, Fords and Chevys, etc?

 

Ztec or the VCT motor is fords version of variable valve timing or variable cam timing in this case... all motor companies have some form of it.. Honda has it down pretty good though.. I drove a prelude with the Vtec in it and at about 5 grand you get a "boost" of power allmost like a turbo but no build up to it... it's wierd

 

Yeh you guys are right...

My mistake.. it was too early for me to organize my thoughts..


Honda has VTEC
Nissan has VVL
Toyota has VVTi

I should know about the VVL though since I almost bought an SR20VET for my Nissan Sentra last year. Yeh, the 278 bhp engine found in the X-Trail available over seas. Optional variable valve timing and lift
(Neo VVL)

---------------------
Quote : SR16VR: Nissan's high winding 1.6 liter, 175-hp four cylinder
---------------------

I'm sorry but all VVL engines that I know of are in the SR series end with an VE.

Also the Nissan Z32 had an option of Variable Valve Timing, as well as the VQ35DE found in pathfinders, maximas and altimas, and the VK45DE in Infinit Q45's and the VE30 engine in Maxima SE's and the QR25DE in Sentra SE-R's in 2001 but it's continous variable valve timing control.
Also the QG18DE in 2000+ Sentra's and the GA16DE in Sentra's 91-96?

 

Nissan's webpage about NEO VVL SR16VE and SR20VE, note that it has specs for each engine and that it I was right....

http://www.nissan.co.jp/COMPASS/TECH/VVL/vvl.html

If your going to tell someone they are wrong make sure they are wrong.


Oh yeah and those SR20VETs are crazy engines, all that power in a small SUV. Nissan should have put into a car and made an EVO/STi killer with it, but then again it probably would have given the Skyline GT-R a run for it's money....

 

um.. ur not emphazing i'm wrong right? LoL

 

I have the VVTi in my Corolla, it sucks, or rather doesn't do anything noticeable. I have the auto so when I just stomp on the gas a little, the VVTi seems to increase the RPM by around 3-500 RPM without downshifting, so you get a little more kick than you normally would. To get any useable power you have to stomp the gas and get the tranny to downshift, but you feel no difference between it and a standard engine.

 

that was uncalled for



Post Edited (Apr 8, 9:26pm)

 

what was???

 

check out the threaded view

 

i'm confused

 

you guys are going off topic

 

toyota has 2 dif. 'vtec' type engines. the vvti, and the vvtl-i. the vvti is their basic variable timing engine. the vvtl-i is the one in the celica gt-s. Wich is one bad ass car, take it for a drive if you ever get the chance. 1.6 litre enginge...runs a stock 15.5 in the quarter and tops out around 160 or so all stock. from 5-7 grand the variable timing and lift kicks in and the power it generates in just insane.