Thread: Is there any documentation showing when VVL was invented?

yep vtec came out on the b16a in 1989.
Nissan and many other manufacturers no doubt copied the design

Edited for correctness.

cheered for correcting

When I think of VVT I think of electronic control of "timing" of the valves. When I think of VVL I think of manual variation of valve lift due to engagement of larger cams.
Would that not be different? Or maybe I am stupid and don't understand VVT?

97 VVL

88 CRX Si-R came VTEC 1.6 an yes the suspension on the 88 is similar to type R

Only newer honda motors have VVT as well and variable lift. To me, variable timing is something that can change over many different ranges of the rpm band. simply changing one static timing event due to "changover" doesn't really cut it to me.

Take Toyota's VVTLi system. Variable lift, and variable timing events. Just like the new VVEL system on the Vq37 and the iVtec system on Honda's K20.

To have variable timing, there should be some sort of hydraulic cam gear. Though some advertise "timing" even though it is a change in the cam profile, not really the timing.

Does this make any sense?

Although I believe the VVL system is better than the ole Vtec, it certainly cannot keep up with the new iVtec system.

this is just my opinion to clarify on things...i'm not singling anyone out...



^^^

= equals

performance iVTEC (which IS continuously variable valve and intake cam timing over many different ranges of the rpm band)




the fact that there are 2 cam lobe profiles on a VVL/VTEC, when the changeover occurs, this directly varies/changes only the valve timing, lift and duration.




this is true. this is in reference again to the performance iVTEC, which has continuous variable intake cam timing and (variable valve timing, lift and duration). the intake camshaft is capable of advancing between 25 and 50 degrees during operation. cam timing changes are implemented by a computer controlled, oil driven adjustable cam gear. cam timing is determined by a combination of engine load and rpm, ranging from fully retarded at idle to maximum advance at full throttle and low rpm.




Toyota's Dual VVT-i system is more closely related to VVL/VTEC. the other comparison is Nissan VVEL/BMW Valvetronic/Honda A-VTEC/Toyota Valvematic.




vvt started out at mechanically back in the steam engine days. the 1987 nissan Z31 300ZX was the first production car to use electronically controlled VVT using NVCS (Nissan Valve-Timing Control System). VTEC/VVL uses ecu controlled solenoids to initiate the cam switching.




thor's first post was dead on. honda first invented the system that gives an engine the ability to operate on two completely different cam profiles, thus VTEC. then nissan improved on it with VVL, and soon after, honda perfected it with the performance iVTEC.



now all things aside, back to the main topic. we don't know exactly when nissan developed vvl, but like HKS P10 said, nissan started using it in 1997.

I would relate the real VVTLi to more of the performance iVtec. It has a hydraulic intake with variable intake cam timing, along with lift. It just doesn't have it on the exhaust side like the Honda's and Nissan's new systems.

But that's just me.

i'm sorry i was wrong. i corrected my above post to this:



dual vvt-i has both intake and exhaust valve timing...