Comments on: Toyota reveals Valvematic technology

By: sahad

sahad — Sun, 10 May 2009 11:33:03 +0000

hi Im very like vvt-i but I need more information about valvematic

By: The Sabahan

The Sabahan — Tue, 28 Apr 2009 04:02:06 +0000

just too add, valve throttle engines do have any throttle butterfly or flaps to control air and instead uses the cam lift. bmw’s valvetronic and nissans vvel does the same.

By: The Sabahan

The Sabahan — Tue, 28 Apr 2009 03:56:09 +0000

the primary reason for such technology is to improve low end swirl which multivalve engine suffer that is why these engine tech is coming around. apparently the highest speed the intake air travel is through the throttle butterfly choke area(i am talking normal driving conditions) and valve opening time but the problem if you have the throttle body is that it created turbulance that hampers whatever potential the air going round the valve could muster. using the valve as throttle, on low throttle application, the highest speed of air would be generated around the valves into the combustion chamber resulting in quicker air velocities into the combustion chamber for both better atomization and swirl. swirl, determines the speed of explosion (combustion) so having a good swirl for better burning during low rpm is ciritical especially with these modern 4 valve 6500 redline engine. the turbulance too would be generated in a non-critical area which would be the combustion chamber where swirl is near turbulance itself. proton should look into this and mate it with direct injection on a very high compression ratio petrol engine if proton still fail to produce any high tech turbo diesels.

to cut it short, this technology draws high velocity air even when the engine is operating on low velocity. it bring the efficientcy of both advantages together.

By: bernauli

bernauli — Sun, 20 Jan 2008 12:42:39 +0000

there is no throttle valve, this is the importance of this engine, can you all imagine!! if you push your gas, because there is no throttle valve the cam would go deeper push the valve and regulate the air!!! it’s not about the vtec or vvti it is the combination of those……i just imagine, are this kind of engine still need an super engine cleaner!! because most of it, just function to clean the throttle valve

By: New Toyota Corolla Altis for Malaysians in 2008

New Toyota Corolla Altis for Malaysians in 2008 — Wed, 12 Sep 2007 12:26:34 +0000

[...] 2.0 liter 3ZR-FE Dual VVT-i engine making 143 PS, but if we’re really lucky we could get the Valvematic 3ZR-FAE which makes 158 PS at 6,200rpm – this would make the Toyota Corolla Altis 2.0 liter Valvematic the [...]

By: Toyota Noah with Valvematic engine!

Toyota Noah with Valvematic engine! — Sat, 30 Jun 2007 17:14:41 +0000

[...] of the first few cars to feature Toyota’s new Valvematic engine has been unveiled – the new generation Toyota Noah (and it’s more aggressively-styled cousin [...]

By: kanazai2001

kanazai2001 — Thu, 28 Jun 2007 06:10:43 +0000

ironically, first VALVEMATIC engine of toyota found in a VAN… NOAH and VOXY (both are the same but with different trims); it is the new 3ZR-FAE:
Total cubic displacement: 1.986 L
The highest output : 116kW (158PS) /6,200r.p.m.
Largest torque : 196N m (20.0kg m) /4,400r.p.m.

By: mystvearn

mystvearn — Sat, 16 Jun 2007 11:07:43 +0000

Does the honda A Vtec works the same way?

By: jamsbong

jamsbong — Fri, 15 Jun 2007 14:55:36 +0000

Hi guys,
The Miller cycle is design to be efficient. However, it is certainly not powerful on its own. Also, millar cycle does not have to be force-fed, ie. no turbo-charging necessary. Prius’ 1.3L engine is an example. non-turbo and saves fuel, but no great power.

The basic principle is that if you have less volume of compress, then u need less effort thus less energy loss from the compressing stroke. Which is why valves are closed late. At the same time, the expansion stroke will travelling fully to the bottom, salvaging as much energy as possible on the power stroke before the exhaust valves are open.

All automotive companies today are getting a lot of pressure from regulations so that less CO2 and other pollutants are produced. This is the main reason why smart valvetronic and other technology are coming up. There are other reasons, but this is the biggest reason.

By: The Unicons

The Unicons — Fri, 15 Jun 2007 02:44:59 +0000

Having new technologies especially with cleaner emission is good for our environment and to our earth. However if fuel efficiency is concern, I don’t think it is 100% true. It’s all depends on how you drive. Usually calculations have been done on 90KM/h or 100KM/h either urban or city driving constaintly in speed. If you drive the car like turtle having this 2 litre valvematic VVT-i engine, it will cost you even more plus, you actually might spoil your engine and transmission as it always keep in low gear and engine doesn’t really working up…

I’ve been looking many people driving like turtle even on right line.

By: bmpower

bmpower — Thu, 14 Jun 2007 01:29:18 +0000

typically toyota , alway said “fuel efficiency”.
but does it really do?. prtffffff..

By: king

king — Wed, 13 Jun 2007 17:23:26 +0000

no big deal…..other european marques already using this tech long time ago…toyota is playing it safe by letting others bcome guinea pig. then they use the same tech and make a big hoo-haa out of it. their engines have always been outdated especially the diesels in the “new” hilux ( underpowered plus high consumption)…they save the best only for lexus( but you have to pay dearly for it) while toyotas get cheap ancient motors with cekap name only.

By: shooter

shooter — Wed, 13 Jun 2007 13:26:03 +0000

if its running on a modified miller cycle, shouldnt it be forced fed?

By: shooter

shooter — Wed, 13 Jun 2007 12:50:04 +0000

anyone seen the dyno graph for this new engine? i want to see those curves, it puts the the paper output into perspective….

By: azolkipl

azolkipl — Wed, 13 Jun 2007 12:29:05 +0000

miller cycle power gains can only be accomplished if you can provide more volume of air during the intake stroke, as you leave the intake valve open longer into the compression stroke (meaning air will leave the chamber thru the intake vavle). And most write-ups about it always suggest turbos or superchargers.

By: adlanar

adlanar — Wed, 13 Jun 2007 12:16:28 +0000

sorry, that should read atkinson cycle. miller cycle is when the intake stroke is compressed. the old xedos used a combination atkinson-miller hence the confusion between the two. been a long time since my engine final year project.

By: adlanar

adlanar — Wed, 13 Jun 2007 12:12:53 +0000

its just running the engine in miller cycle as opposed to normal otto cycle.
mazda have been experimenting with this for a long time. the old 626 xedos had miller cycle engines in japan and some euro market. now they’re doin it on small engines starting with the new mazda2. running on miller cycle does give better fuel economy as the combustion gases are allowed to fully expand throughout the exhaust stroke. slight performance increase are usually gained as well.

By: LittleFire85

LittleFire85 — Wed, 13 Jun 2007 11:31:59 +0000

Well if we are the engineers of the P1/P2 i think the car industry will be even better.. but sometime is not the engineers fault, but is the management.. Louzy management..If the head is useless the rest will be useless also… Is like having good strong body but with a brain of a prawn… Haiz…

By: torishimeyakuin

torishimeyakuin — Wed, 13 Jun 2007 11:23:17 +0000

Or is there any possibility that, most of you guys above are the engineers who are already working at Proton or Perodua ? Hehehe…No offence please just kidding.

By: torishimeyakuin

torishimeyakuin — Wed, 13 Jun 2007 11:16:50 +0000

Woww you guys here above are really somebody !! Seems that most of you are very good and having such profound knowledges pertaining car’s engines. Impressive !!

I think Proton or Perodua should hire some of you guys….really, i really mean that.

By: jamsbong

jamsbong — Wed, 13 Jun 2007 09:51:10 +0000

Looking at the design patent, this system looks really brilliant. it is much like honda’s system. from the patent design, there looks like there are 3 different variation.

Toyota has elected to have a separate space away from the camshaft to do these tricks. This is much like the VVT-iL system. Honda’s system looked more compact.

In terms of power output from the 2L engine. I would say the engine is tuned for efficiency and good response. With a different setup, the potential is there to make the engine go wild.

The difference between a non-vvt engine would be the response. Yes, non-vtec engine probably has about the same output or oven higher, but it will be horrible at the low end. Just have a look at some OLD porsche’s engines and you’ll be surprise that big HP in a small engine had been around for a long time.

By: BanyakMasukWorkshop

BanyakMasukWorkshop — Wed, 13 Jun 2007 09:07:51 +0000

toyota always had sound, reliable engineering. whatever the technology behind it, they will definitely make it available everywhere, and at an affordable cost. now if only they could make some cars with soul like they used to.

By: proton GL

proton GL — Wed, 13 Jun 2007 08:40:19 +0000

anyway it means to optimised the engine breathing through out the rev range in what ever mean to control the amount of gases, and gives best swirl effect for low rpm combustion, any acceptable design then pattened,

about the cps of proton it is said to be developed from vario cam, which is by adjusting the timing chain to alter the cam timing, but the engine design doesnt likely to fit the existing engine,
the possible machenism they might use is the one from vario plus, which is vvt with 2 stage lift, which might be as good as vvti-L

and the tunable intake could further improve lower end as is if lower valve lift in effect though not instantinously like valvetronic.

——
anyway what i recon now is the engine become more complex but of course for good,
anyway still admire the simplicity of TSI for more gain.

By: Paul Tan

Paul Tan — Wed, 13 Jun 2007 07:04:17 +0000

VVTL-i is not continuous (stepless), it just switches between 2 lift stages.

By: LittleFire85

LittleFire85 — Wed, 13 Jun 2007 06:54:15 +0000

I tot i read it somewhere that the new toyota valvematic is a replacement of Toyota VVTL-i engine… Valvematic*, a variable valve lift mechanism created through combining VVT-i (Variable Valve Timing-intelligent), which continuously controls intake valve opening/closing timing, with a new mechanism that continuously controls the intake valve lift volume.

You can see the toyota VVTL-i rocker arm in below.. almost the same with Valvematic..

http://www.autozine.org/technical_school/engine/vvt_31.htm

VVTL-i animation:

http://fr.toyota.be/innovation/technology/glossary/gloss_vvtl_i.aspx#

By: azolkipl

azolkipl — Wed, 13 Jun 2007 05:44:09 +0000

Dynamic Lift and Cam phasing in ANY engine is definitely a benefit, as it allows the engine to adjust to different kinds of driving ’styles’. If you press on the pedal hard to get more power, the valve lift and cam phasing could be adjusted to allow more air and fuel in longer to give better power performance. If you are driving in ‘economy’ mode, the lift and phasing can be adjusted to allow optimal (minimal) amounts of fuel and air to not waste energy. Normally, a normal driving behaviour would always include overtaking maneuvers, stop-and-go driving and long set-speed drives (highway). Now, with dynamic lift and phasing engines, you can get benefits of better fuel consumption, better power delivery, better torque, AND better emissions in a single engine. That’s what AVTEC, valvetronic, bi-vanos, and valvematic is all about.

By: fandango

fandango — Wed, 13 Jun 2007 04:30:56 +0000

I think the main benefit of having continous valve lift and timing is the shape of the powerband, especially the torque curve. no doubt the PEAK hp and torque figures may seem ordinary, but the technology enables far better throttle response and drivability by raising the torque curve early on and keeping it there over a longer part of the rpm range. all this is coupled with better emissions and economy.

so far bmw has it (valvetronic+vanos), honda (avtec) and now toyota. not sure who else has it. as for proton’s campro, i think it’s just an intake cam implementation of a variable valve timing mechanism. something that toyota first served up in 1992.

By: floyd

floyd — Wed, 13 Jun 2007 03:45:03 +0000

is this something new from toyota? i doubt it. They always do it later than the other giant car makers…hmmm…. but they do it right most of the time.

toyota’s common rail for diesel engines are behind the others in term of tuning and power output, or did toyota make their diesel cars less powerful for reasons known only to them? Toyotas still using older common rail when others are already on 2nd generation.

By: kanazai2001

kanazai2001 — Wed, 13 Jun 2007 03:18:54 +0000

comparison between BMW, Honda and Toyota:
(A) continuous variable valve lifting – BMW valvetronic
(B) cam profile switching – Honda VTEC
(C) continuous variable cam phasing – Toyota VVT-i

(B) + (C) = Honda iVTEC, Toyota VVTL-i
(A) + (C) = BMW VANOS, Honda AVTEC, Toyota Valvematic

correct me if im wrong. argument?!

latest trend is (A) + (C) because it reduces throttle loss, CO2 and toxic gas emission.
(B) – out dated. that is why toyota and honda are going for AVTEC and Valvematic.

no offend to all VTEC admirers.

By: ganz

ganz — Wed, 13 Jun 2007 03:12:27 +0000

good info…
BTW.. i still waiting our OWN valve technolgy from PROTON… the much awaited.. CAMPRO