WHY VTEC IS WAY BETTER THAN VVTI

[Qwooootz]

im real interested in the techinical side of things can any1 help me out or lead me to a similar thread.. thankz

[XXpl0Sive]

The Toyota engines seem to run slightly more aggressive cams than the Honda's, and so at lower revs they seem to (anecdotal evidence here ...) be a bit more pleasant to drive and make a little more power. There's also less of a transition when the cam shifting systems operate, but this is obvious due to the Honda system swapping over to a much more 'racy' cam profile.

Pro's - Both systems allow you to have an engine that's quite a lot more powerful and yet still driveable than a 'conventional' engine would otherwise possibly be. The V-TEC is the obvious choice for outright power, and the Honda's certainly seem to rev a heck of a lot more than the Toyota's do. (The S2000 red lines at a stratospheric 9,000rpm - stock!)

Con's - You are pretty much stuck with limited modifications to the engine, eg, air filters, extractors, etc, to get more power. The reason for this is the very system that give the engine all that extra power - The cams & VVT/V-TEC. You can of course use larger cams to get more power, but this defeats the purpose of having the VVT/V-TEC in the first place. You'll most likely lose power at low revs, and not gain a great deal at high revs. (The VVT will gain proportionally more than the V-TEC, however, as the V-TEC head is optimised - well, compromised - for the 'big' cam & 'small' cam and so using a larger cam may not help much at all)

So, if you want an engine with power like a racing engine, then you're better off building a straight race engine right from the start. Or maybe a turbo engine ...

The other concern I have is the longevity of these sorts of engines. I believe that the VVT system would be largely trouble free for the life of the engine provided that you keep the oil clean and change it regularly. Even more so with the V-TEC, as with all it's little bits & pieces in close formation in the head I'd hate to think what would happen if some of those little locking pins didn't engage properly at 6000rpm+. All that being said though, I have it on reliable advice that Honda have never had a warrantee claim for any V-TEC engine in the area of the head and/or valve gear. Quite impressive.

I think that perhaps the best long term solution to getting large amounts of power from a relatively small engine is still by using a turbo, but if you like to hear the engine scream at high revs then one of these two systems is the way to go.

From http://www.billzilla.org/vvtvtec.htm

[SIKCVC]

uuuummmm last time I checked VVTi is Variable Valve Timing, not Varable Cam lobe possitioning.

I'm pretty sure I've read a few times, That VVTi meirly Shifts the Cam shafts into a different timing possition (ie advance the timing) so fuel is injected earlier in the revolution.

I mean the name says it all doesn't it... VVTi stands for Variable Valve Timing (intelgence? Injection? something along those lines) the key word there Timing not duration, not Lift.

But I'm only going on what I've read a few times on MCCR I'll try and find the link to the site that explains all the forms of change in Valve timing etc, I could be mistaking it for Vanos (BMW) or nissans version of VVT. But I will find out.

[XXpl0Sive]

Yeh see if you can find more information and post it up. Find out how Nissans' VVT works with the turbo. VVTi-L is the Lift version (simlar to VTEC) that Toyota devised.

[SIKCVC]

OOOHHHH thats what they have... see i must have been thinking of VVTi which I was sure was only timing adjustment on the fly, so they do have a VTec spin off... Kool.

[XXpl0Sive]

Yep it's in the newer Celica's :)

[SIKCVC]

heres the Link... [post edited after reading the page again :P]

http://www.billzilla.org/vvtvtec.htm

[SIKCVC]

and after reading i take it its the same link you quoted :P

[pornstar]

Xxplosive, where did u get all those misconceptions from man?

I dont see how having a more agressive cam is going to defeat the purpose of VTEC?

I dont see how having VTEC or not limits power either, if anything it helps make more driveaboility for big hp engines using high revs.

Overall man, what u just posted is so mis-informed man.

[SIKCVC]

those Neo Sr 1.6 VVL engines make the same power as a JDM B16a :P there was one for sale recently.

[crx2gen]

read this, should give you a pretty good idea.

http://autozine.kyul.net/technical_school/tech_index.htm#Engine

[wynode]

Overall man, what u just posted is so mis-informed man.

I agree.

Not only is VTEC spelt wrong but it overlooks the fact that VTEC/VVTL-i allow you to run a lumpy cam on the street without sacrificing a smooth idle and low RPM pulling power.

As for Nissan, the SR20VE is the only engine (AFAIK) which has variable valve lift and was found in the primeras in Japan. The SR20DETs found in the 180sx etc only have variable timing and I belive thats only on the intake (or was it exhaust) cam.

As for the title, you cannot compare VVT-i with VTEC. The proper comparison is VVTL-i with i-VTEC, where both allow continously variable valve timing.

I posted a link up in regards to the SR20VE someone around here so search for it if you wanna learn more!

Ok now lets discuss VVTL-i vs VTEC/i-VTEC!

[mo]

VTEC SUCKS!! :P

[[zeth]]

http://img28.photobucket.com/albums/v85/accord94dx/419/PEDROVTEC.jpg

[Jus-10]

OK, here are some basic specs of the engines. The first one is the Toyota engine found in both the Celica and Corolla Sportivo. From my understanding, this is the only engine offered out here with VVTL-i....all the rest are VVT-i.

As you can see, it is all pretty similar from a pure numbers game....


2ZZ-GE
1796cc (1.8 )
DOHC with VVT & Lift
141kW @ 7800rpm
180Nm

K20A2
1998cc (2.0 )
DOHC with VVT & Lift
147kW @ 7400rpm
192Nm

B18C7
1797cc (1.8 )
DOHC with VVT
141kW @ 7900rpm
172Nm


*edit* these figures were taken from www.redbook.com.au

[[[d a n n y]]]

OK, here are some basic specs of the engines. The first one is the Toyota engine found in both the Celica and Corolla Sportivo. From my understanding, this is the only engine offered out here with VVTL-i....all the rest are VVT-i.

As you can see, it is all pretty similar from a pure numbers game....


2ZZ-GE
1796cc (1.8 )
DOHC with VVT & Lift
141kW @ 7800rpm
180Nm

K20A2
1998cc (2.0 )
DOHC with VVT & Lift
147kW @ 7400rpm
192Nm

B18C7
1797cc (1.8 )
DOHC with VVT
141kW @ 7900rpm
172Nm


*edit* these figures were taken from www.redbook.com.au

b18c7?

k20?

toyota?

aint that ITR engines?

[XXpl0Sive]

Overall man, what u just posted is so mis-informed man.
The SR20DETs found in the 180sx etc only have variable timing and I belive thats only on the intake (or was it exhaust) cam.

180sx don't have VVT, only S14a and S15s :?
SIKCVC, yep same site!

[Jus-10]

What are you on about Danny?

2ZZ = Toyota Celica/Corolla Sportivo

B18C7 = DC2R

K20A2 = DC5R

I simply posted these Honda figures as they are the closest match to the Toyota unit in terms of specs.

[pornstar]

yeah but those power figures are VVTI-L, both variable cam and cam timing is used.

The VTEC is simply Variable Cams.

[Jus-10]

So compare the 2ZZ with the K20

[A'PEXi]

ek9 beats a 2000 celica down the quarter... hint hint :D

[Javed]

Wow it looks like Toyota have done well, I was lookign at a corolla sportivo couple of weeks ago, oddnt drive 1 tho :P :( It seems the 1.8 pulls near the power of the K20. Wonder what they could achieve with the .2L more displacement? On a side note what weight does the corolla carry? Might be able to keep up with a DC5R ;)?

[tofu R]

BIG "WTF" ...

I'm full lost as to why 90% of the stuff thats been posted in this thread has been posted..

hugely wrong info here ...
hmm i have no doubt in my mind the corolla would be slower than the celica, which is slower than a VTiR integra,

if u want to compare spec sheet for spec sheet..

the celica's power/figures are VERY similar to that of a DC2R..
but if u actually go and drive instead of reading quoted figures .. u will find
that the only thing similiar is they have 4 wheels and a steeringwheel (ok a bit exaggerated)..

no way a stock celica can keep up with a DC5R

[mo]

Corolla Sportivo = 1224kg
DC5R = 1160kg

[Javed]

I would have thought the 2ZZ would beat a VTiR...

[SiR]

On a side note what weight does the corolla carry? Might be able to keep up with a DC5R ;)?

Doubt it - the Sportivo is quite porky at 1224kg

I heard the Sportivo has a knack for dropping out of the powerband in between gears so that would also go against it.

[stocky]

Just useless info

but my B16A got beat by a 1zzfe (ascent corolla) with intake and 2" exhaust

[mo]

Just useless info

but my B16A got beat by a 1zzfe (ascent corolla) with intake and 2" exhaust

ascent rolla...aren't those 100kw ones? crap driver? :P :twisted:

[Weq]

Look at adyno graph of a sportivo colrroa/celica. the power is not useable.. comes on and peaks ina very small period of time.

[SiR]

Just useless info

but my B16A got beat by a 1zzfe (ascent corolla) with intake and 2" exhaust

ascent rolla...aren't those 100kw ones? crap driver? :P :twisted:

LOL~

[wynode]

Overall man, what u just posted is so mis-informed man.
The SR20DETs found in the 180sx etc only have variable timing and I belive thats only on the intake (or was it exhaust) cam.

180sx don't have VVT, only S14a and S15s :?
SIKCVC, yep same site!

The Black top (or was it the red) has variable timing. Have a look at the end of the cam shaft near the timing belt.

[madgrk]

Yeah its the black top that has it.. mmm the power of the almighty SR20

Red top is off the S13 series, and the S14. As XXpl0Sive said the S14a got a blacktop

[XXpl0Sive]

Overall man, what u just posted is so mis-informed man.
The SR20DETs found in the 180sx etc only have variable timing and I belive thats only on the intake (or was it exhaust) cam.

180sx don't have VVT, only S14a and S15s :?
SIKCVC, yep same site!

The Black top (or was it the red) has variable timing. Have a look at the end of the cam shaft near the timing belt.
No they don't. There's red tops, and then there's black tops, and then there's black tops WITH VVT, you can tell a black top has VVT because the rocker cover is sloped at the back ;) The black tops that are sloped are evident in later model SR20's.

[SPEEDCORE]

CORRECT XXplosive!!

[pornstar]

yeah but ur long post at the start is still misinformed.

Unless u care to answer, why VTEC is not good for having killer cams, etc etc

[TODA AU]

LOL....
This is some funny shit....
Sorry...
Keep going...

[McChook]

Look at adyno graph of a sportivo colrroa/celica. the power is not useable.. comes on and peaks ina very small period of time.

There's the truth...
Took a long time for that to come out, but finally, someone sais it.

The Celicas are slow, the sportivos are slower - however, the sportivo corolla is the biggest bargain small car on the road under $33000.

Niether Toyota is any fun to drive - in fact they are dull and fireless....

[SIKCVC]

hahaha

[Javed]

Yeah corolla sportivo brand new driveaway for $29, 990 is what I was after the other week. I reckon its look like good value for money, but I decided to stay true to Honda after Toyota's dealers insulted me with a trade in price for my beloved integra. Like I said to them "for me, buying a toyota is a downgrade" haha.

[stocky]

Just useless info

but my B16A got beat by a 1zzfe (ascent corolla) with intake and 2" exhaust

ascent rolla...aren't those 100kw ones? crap driver? :P :twisted:

LOL~

yeah, the 100kw ones, but he had an intake, exhaust
oh well, im a crap driver then but line me up and we'll see who's crappier :twisted:

[mo]

Intake and exhaust gives next to no gain...lol
Or do you want to be liks this guy
http://forums.clubrsx.com/showthread.php?t=161934
Who believes his exhaust system will give 15% more torque and a 15-20kw gain in power LOL!!!

I'm not saying your a crap driver...if you noticed my "?" But obviously you are trying to imply that you are some king of the road since you are trying to tell me that I am a shit driver (well I am)

But hey...B16A losing to a crappy grocery car...lol...

[Javed]

OOOOOOO... bring out the NOS!!! :D hahhaha

[SIKCVC]

Like I said to them "for me, buying a toyota is a downgrade" haha.

HAHAHAHA love it LOVE IT!!!

[stocky]

I'm not saying your a crap driver...if you noticed my "?" But obviously you are trying to imply that you are some king of the road since you are trying to tell me that I am a shit driver (well I am)

But hey...B16A losing to a crappy grocery car...lol...

haha, no worries, but yeah.....just trying to say that those rolla's aint that slow and a b16a aint all that.

[Javed]

Hehehe yeah. I also gave the Toyota dealer the hardest time cause he thought just because I was younger he could give me the learning curve style. I put him in his place, basically saying at the end of the day to fu*k off. No way can they expect me to part with my honda that cheaply, bastards! Same with all dealers though, scum, scum, scum! But yeah in the end Honda>Toyota :D

[mo]

I never said rolla's are slow...but maybe my experience was totally different from yours ;)

and yes a b16a ain't all that...Is yours stock may I ask?

[SPEEDCORE]

G/F smashed a Sportivo going around brisbane in her EK4, looser flybyed her. :roll:

TOFU from these forums also had a run in with the same guy and from what I heard blasted him with his Auto DC5. LOL.

[SIKCVC]

uuuummmm no offence but I'd be depressed if a 100kwt rolla beet me with my 96 or 100kwt ZC (i have NO idea which one it is :P it has an OBd1 Ecu though with Vtec plugs and everything WHERES THE VTEC!!!) Maybe something went wrong when you raced coz even the good ol ZC would have held them down no worries.

[ECU-MAN]

I have it on reliable advice that Honda have never had a warrantee claim for any V-TEC engine in the area of the head and/or valve gear. Quite impressive.

I 2nd that

[Qwooootz]

hahaha this thread has become very entertaining..

[wynode]

I will give this a few more posts to come back on topic.

[Qwooootz]

well nones really answered the question yet hehe.. i can only see biased opinions, :roll: lol but from experience VTEC is a far more complex and >ADVANCED< than any other copies :P

[ECU-MAN]

well nones really answered the question yet hehe.. i can only see biased opinions, :roll: lol but from experience VTEC is a far more complex and >ADVANCED< than any other copies :P

na man I disagree (and Agree)
Advanced yes
complex no.

Varable valve timing has been round for years. I might be wrong here but Volvo ( I think ) tried it in the 70's but couldnt make it to production, as useual the Japs copy the Idea and perfect it and put a Paitent on it. Im thinking Honda developed it during the late 80's got it right and put it in production in the early 90's. the way Honda did it was simple. coz of the paitent no one can copy this Idea of a 3rd cam lobe concept so other manufactures are the ones with the complex varable valve timing systems.

I dont know how toyota do it so I cant comment on the original question

[SIKCVC]

Didn't honda implement into their F1 car first? in like 86 or something? I dunno i mix figures up in my head all the time.

[bizee_1]

maybe the rolla had a 20V under the bonnet ? [those 20V had vari-valve timing too]

read this, should give you a pretty good idea.
http://autozine.kyul.net/technical_school/tech_index.htm#Engine
hey thankx for that site ! lost it, now i've got it again.

im real interested in the techinical side of things can any1 help me out or lead me to a similar thread.. thankz
Here are some other sites to read :
http://www.motioncars.com/archive/tidbits_feature19/main.htm
http://www.edmunds.com/news/innovations/articles/43849/article.html

IMO, VTEC is better than VVT-i, because there are more aftermarket parts, our gearboxes are well matched & performance overall is better. [otherwise we'd all be drivin' Toyota's right ?!?]

In the end, they are just higher-tech, more efficient & powerful engines despite what marketing strategies they use.

[TODA AU]

Toyota VVTLi is pretty damn good to tune...
I'd put it on par with Honda DOHC VTEC...
I've tuned both & though a little different the end results are both really good...
That is a well tuned Celica is line ball with a well tuned DC2R.
Infact, bang for your bucks, the Celica actually responds better...
(Using Power FC)
The Toyota 2ZZ engine btw is an exellent engine, closer to the F20C in construction than B or K series engines...

[Setanta]

VTEC SUCKS!! :P

From performanceforums:
k3nnis: Can you explain how VTEC feels like when it kicks in? Does it pin you back to the seat a little bit like a turbo?
sejanus: Imagine a incredibly tiny small turbo that for some bizarre reason takes 5500-6000rpm to make boost, and so small that it makes bugger all power, just an increase in noise.

:D :D :D

[Setanta]

well nones really answered the question yet hehe.. i can only see biased opinions, :roll: lol but from experience VTEC is a far more complex and >ADVANCED< than any other copies :P

Incorrect. All are a means to an end, utilising the same principle if we are comparing VTEC and VVTi-L, not the VVTi that your original post uses as a poor man's argument. Comparing VVTi to VTEC is like comparing a B16A to a SOHC VTEC motor. They are nothing alike in principle.

Toda AU covers it nicely.

[SPEEDCORE]

Doesn't the i-VTEC have variable timing also??

If so shouldn't the VVTL-i be compared to the i-VTEC?

[Qwooootz]

well nones really answered the question yet hehe.. i can only see biased opinions, :roll: lol but from experience VTEC is a far more complex and >ADVANCED< than any other copies :P

Incorrect. All are a means to an end, utilising the same principle if we are comparing VTEC and VVTi-L, not the VVTi that your original post uses as a poor man's argument. Comparing VVTi to VTEC is like comparing a B16A to a SOHC VTEC motor. They are nothing alike in principle.

Toda AU covers it nicely.


okie doki my bad... VTEC VS VVTL-i


Bizze_1 thanks for the links dood gonna read up on em'!

[**Ghost**]

In brief

VTEC is better than VVTI-L (woteva)

because.............


its made by honda, its in a honda..

[TODA AU]

Doesn't the i-VTEC have variable timing also??

If so shouldn't the VVTL-i be compared to the i-VTEC?

Not exactly...
Toyota VVTL-i offers variable lift & timing...
But not varable duration as Vtec does...
Still not apples & apples...
DOHC Vtec & VVTL-i though different are relativly comparable...
i-VTEC goes one better...
With both variable lift, duration & timing....
Next will probably be varable timing on the exhaust side also... :?:
If you do comapare the two systems...
IMO the Honda system is superior...
That is to say, the VVTL-i can be made to match the output of DOHC Vtec... (same capacity etc, similar mods etc)
The problem with the Toyota system is the lack of aftermarket support...
Moreover the lack of demand for these parts & therfore the lack of availablity due to no market...
At the end of the day... To different approches to the same/similar end...
Myself, I like them both...
Cheers

[pgclee]

must remember...whois the real Valve Timing master...honda...they are the one who develop it..so...i think that is why...do you think a copy is better than a real stuff?

[Setanta]

Stupid response number #88 from pgclee. Honda didn't develop variable valve timing, they refined it and put it into mass production. This was already mentioned in another post.

[mo]

Lay the smack down Pete :D

[VTEC16]

Stupid response number #88 from pgclee

LOL you harsh kunt!

[wynode]

Toyota VVTL-i offers variable lift & timing...
But not varable duration as Vtec does...


I was under the impression that VTEC only provides variable lif and timing. Wouldn't you have to change the lobe profile to have variable duration? I belive Porche's variocam is capable of this.



i-VTEC goes one better...
With both variable lift, duration & timing....
Next will probably be varable timing on the exhaust side also... :?:


I thought the main difference b/w VTEC and i-VTEC was continuosly varliable timing in the latter ?
Also.......i-VTEC has continuosly variable timing on both cam shafts I'm pretty sure.

[TODA AU]

I was under the impression that VTEC only provides variable lif and timing. Wouldn't you have to change the lobe profile to have variable duration? I belive Porche's variocam is capable of this.

I thought the main difference b/w VTEC and i-VTEC was continuosly varliable timing in the latter ?
Also.......i-VTEC has continuosly variable timing on both cam shafts I'm pretty sure.

Normal DOHC VTEC provides variable lift & duration.
(Not actual timing as such)
Timing remains constant except for the change in lobe centres fixed within the manufacture of the camshaft, when cam profiles are swapped.
Such as would be offered by a low cam of 190deg @ 7mm lift (116 LCA)
& high cam of 240deg @ 10.2mm lift (107 LCA)
The i-VTEC adds + or - 25deg to the lobe centre angle of the intake camshaft only.
For the sake of example, the same cam as above...
With an intake LCA of 90deg~140deg
This is a change in timing.

The Toyota system on the other hand doesn't change profiles so the total duration remains the same, but the lobe centres & lift are affected.

[wynode]

The i-VTEC adds + or - 25deg to the lobe centre angle of the intake camshaft only.

Oh I could have sworn it was both intake and exhaust......thanks for clearing that up.

[crx2gen]

Regarding the 1ZZFE Corolla's...15.8 stock apart from 205/40/17's and a big arse stereo :). Not blindingly quick by any means, but respectable for a shopping cart. Why buy a Sportivo when it would be so much easier to simply burn the cash?

[Grimlock]

My friend owns that corolla that beat the b16a on numerous occassions.
Though VTEC is amazing it lacks the initial Torque.
I was there the night it happen.
Both cars had a passengers one so it was a far race.
To determine outright speed, from start to finish, they did a sprint to the end of fourth gear. The rolla was ahead all the way by half a car length. Approx speed not more than 100kms over set road limit.

[TODA AU]

Though VTEC is amazing it lacks the initial Torque.

This is more an issue with emission based differential lift low cams rather than the engine itself...
Spec B's solves the lack of initial torque quite smartly.

[pgclee]

Stupid response number #88 from pgclee. Honda didn't develop variable valve timing, they refined it and put it into mass production. This was already mentioned in another post.


hopefully you're driving one quicker than me...

[aaronng]

Oooh.. interesting and entertaining discussion. I was bouncing between buying a Sportivo and Accord Euro, so I did quite a read up and research on the different variable valve systems. Here's my take. Flame me if you wish. :)

First off, there is no point in comparing K20's, B18's and 2ZZ's against each other to DETERMINE whether (i-)VTEC or VVTL-i is better. Because the engines are in different state of tunes. The B18C in the ITR has lightened and matched conrods, lightned and molybdenum-coated pistons, oval springs, lightened valves and crankshaft, optimised intake system and much more, all done by hand at the factory. Obviously it is well tuned, makes more power and will let the engine rev much quicker (i.e. faster response) and this is not necessarily reflected in the peak power which are the only figures that have been quoted.

Toyota's 2ZZ-GE doesn't have any lightened components, just a balanced crankshaft and the MMC liner. It is a mass production engine. And in it are very aggressive cams and the VVTL-i system to compensate for drivablility at low revs.

If you put the B18C and 2ZZ-GE in the same body/chassis, it is obvious that the B18C will be faster to accelerate because of the higher torque below the VTEC point courtesy of the lightened components.

It is not the peak power that shows you how fast your car is (unless you stay at that particular RPM all the time. CVT anyone?) but the total area under the power curve of the dyno chart. The larger the area, the faster your car will be at a given point.

Traditionally, if you put in aggressive cams, your drivability is shot to pieces because the car won't move at low rpms. So imagine 4000rpm take offs from a traffic light or when turning at a stop sign. Not a pretty sound at stand still and bad on your fuel consumption. VTEC, i-VTEC (DOHC VTEC style) and VVTL-i systems that give you variable cam profiles lets you put in aggressive cams and yet have a 2nd set of cams for low end drivability. Look at your (i-)VTEC and VVTL-i as a way to regain drivability and not to make extra power. It is this misconception that cause many people to think VTEC/VVTL-i means extra sound.

No point arguing which variable valve system is better. Because you can say now that VVTL-i gives you more power for such a small capacity! Just swap the VTEC camshafts for ones with more aggressive cam profiles (so many brands offer this in Japan) and suddenly, your Honda engine is making a humongous difference in power at the VTEC zone. But was this increase in power provided by VTEC/VVTL-i? Or was it the cams that provided the power?

In the end, VTEC, i-VTEC and VVTL-i is just a means to putting in multiple cam profiles so that you can have both power and drivability. Like the saying, you can have your cake and eat it. (i-)VTEC/VVTL-i is NOT the cake. It is the ABILITY to let you have the cake and eat it.

just my $2.02

Aaron

[wynode]

In the end, VTEC, i-VTEC and VVTL-i is just a means to putting in multiple cam profiles so that you can have both power and drivability.

Thats pretty much what your whole post said. Good explanation for a noob, but doesn't really compare VVTL-i and VTEC/i-VTEC.

-Win

[aaronng]

Thats pretty much what your whole post said. Good explanation for a noob, but doesn't really compare VVTL-i and VTEC/i-VTEC.

-Win

Thanks, Win. I still find it pointless to compare VVTL-i and (i-)VTEC. Because you can't compare it based on the power it makes like what everyone has been doing. All you can compare is the reliability, the time it takes for it to switch cams and the smoothness when it switches. Power is not produced by the VVTL-i/(i-)VTEC systems, it is produced by the aggressive cams and altered air/fuel ratio by the ECU.

Based on this, in my opinion, i-VTEC should be the most refined of the three.

Aaron

[wynode]

Yes they both do the same thing.............what the topic title is asking is 'which one does it better' "Better" being the hard word to decipher.

[BlitZ]

what is continous variable valve timiing if u dont mind me asking? how many cam lobs can there be? Serious dont know whats goin on here- not trying to be sarcastic....

And jsut a matter of stopping argument sake...
What do u mean by vtec? twin 16v? or single stick.

[wynode]

We're referring to DOHC VTEC (twin 16v?)

Might have to check out howstuff works if you're not sure about what variable valve timing is :)

[muli]

so SOHC VTEC is basically same as VVTI and DOHC VTEC is same as VVTL-I

[wynode]

Not really.

There is no 'equivalent' as such.

SOHC VTEC provides no variable valve timing but provides variable intake valve lift

VVT-i provides variable valve timing, but no variable valve lift.

[Creative]

The missus drives a 2001 ZR celica with vvt-i and I ust admit it goes pretty hard....not as hard as my lude, but still, you have to give it credit :)

The thing just screams when it hits high rpm...but the speed doesnt match the sound imo....but yer....im biased :D

[pornstar]

6 speed gearboxes are nice tho.

[daboss]

most modern fuel injected cars vary the timing regardless of the vvt / vtec or likes... even old fuel injected xf fords varied the timing...

vvt / vtec is an extra system which will increase the duration of the intake, exhaust cams, or both.. etc... this can be done by turning the cam - ie nissan engines or having another set of lobes on the cam as per vtec on hondas

[SIKCVC]

you didn't bother reading the other 6 pages did you. :|

[daboss]

try to put it simple as alot of people dont know what they are talking about

[Limbo]

hey guys try this site it explains all the different types.

http://www.mr2sc.com/websites/articles/vvt.htm

from toyota to honda to porche to fords.

Nearly every manufacturer has some version of it. But i think that Honda's been playing with it more and have spent more R&D on mass producing it and increasing its profile, though toyota is catching up. At the moment i believe i read an article somewhere that the DC5R produces the most ltr to power ratio for a VVT engine.


The first VVT type engine sucessfully made was in 1970 by Fiat., so its been round for a while. http://en.wikipedia.org/wiki/VVT

O another thing Corolla Sportivo weights in closer to 1,400kg. That's why its slow.
MRS & Celica & Corolla sportivo have the same engine. Just a difference in body dynamics and gboxes.

[Limbo]

The different types of VVT i know it still misses some cos i know the Renault & Audi also has VVT

BMW VANOS - Varies intake and exhaust timing and lift by moving the fulcrum of the camshaft
Ford Variable Cam Timing - Varies valve timing by rotating the camshaft
GM Variable Valve Timing - Varies timing (phase) with hydraulic pressure
Honda VTEC - Varies intake, duration, and lift by using two different sets of cam lobes
Honda i-VTEC - Adds cam phasing (timing) to traditional VTEC
Mazda S-VT - Varies timing by rotating the camshaft
Mitsubishi MIVEC - Varies valve timing and lift
Nissan VVL - Varies intake, duration, and lift by using two different sets of cam lobes
Porsche VarioCam - Varies intake timing by adjusting tension of a cam chain
Porsche VarioCam Plus - Varies intake timing by adjusting tension of a cam chain
Rover VVC - Varies timing and lift with an eccentric disc
Subaru AVCS - Varies timing (phase) with hydraulic pressure
Toyota VVT-i - Varies intake timing by advancing the cam chain
Toyota VVTL-i - Varies timing by advancing the cam chain and switching between two sets of cam lobes

[wynode]

The different types of VVT i know it still misses some cos i know the Renault & Audi also has VVT

BMW VANOS - Varies intake and exhaust timing and lift by moving the fulcrum of the camshaft
Ford Variable Cam Timing - Varies valve timing by rotating the camshaft
GM Variable Valve Timing - Varies timing (phase) with hydraulic pressure
Honda VTEC - Varies intake, duration, and lift by using two different sets of cam lobes
Honda i-VTEC - Adds cam phasing (timing) to traditional VTEC
Mazda S-VT - Varies timing by rotating the camshaft
Mitsubishi MIVEC - Varies valve timing and lift
Nissan VVL - Varies intake, duration, and lift by using two different sets of cam lobes
Porsche VarioCam - Varies intake timing by adjusting tension of a cam chain
Porsche VarioCam Plus - Varies intake timing by adjusting tension of a cam chain
Rover VVC - Varies timing and lift with an eccentric disc
Subaru AVCS - Varies timing (phase) with hydraulic pressure
Toyota VVT-i - Varies intake timing by advancing the cam chain
Toyota VVTL-i - Varies timing by advancing the cam chain and switching between two sets of cam lobes
Can you confirm that VANOS changes valve lift?

Also I believe Vario cam only changes cam timing whereas variocam+ chagnes valve lift.

[Northy]

Limbo, the lift component of the VVTL-I is not like V-TEC and so on as the cam profile does not change, its the valve stem that is given an extension to become more aggressive, on another note the MR-S does not share the same motor (2zz-ge) with the sportivo corolla and the celica. The MR-S shares the same engine as the standard corollas a 1zz-fe that runs only VVT-I

[Dnation]

Northy: You're right. The new MR-S only has the 1zz-fe. FE being the lesser DOHC with only variable timing and no lift.

Despite being a toyota fan, I would have to agree that the ITR DC2 is much better than the Celica VVti-L. Sure the Celica has a cool 6spd, but Toyota bodged up the gearing. When u change from 1-2, or 2-3rd, you have to exceed redline IF you want to stay in the aggressive cam phase in the next gear.. But thats the gearbox.. Engine wise, they're very similar. The ITR would probably be better than the VVTiL because of the higher quality internals, but the normal VTiR Integra VTEC will have nothing on the celica..

A good comparison to the new DC5 2.0 VTEC is the Altezza's VVTi-L engine in japan. Thats pretty mean a55 but i dont know much about.. As its made by the flagship toyota brand 'Lexus', they *may* use much higher tolerance levels in building the engine.

On the note of VTEC's though, Im not impressed with the B16A and I'm not surprised that the 100kw Accent corolla beat it. Sure they're fun as hell to wind up to ungodly revs, but they dont go anywhere. They lack bottom end and I think Honda forgot how to make torque. I know this comment will sh1t ppl up the creek but if I were to compare the B16A to other engines near its class, I would put it as a lesser engine than a SSS SR20DE (Torque rocks), on par with the old school TwinCam Corolla's (B16A is slightly smoother), and *just* above the ZC honda engine... Only reason why I bought the B16A for my project civic is for future resale value and I get to rev something over 8000rpm again... Ohh how i miss the revs..

[viperx]

FE actually refers to the angle between the intake and exhaust valves, not to do with variable timing or lift at all. most toyota fe engines run a valve angle of 22.5 degrees whereas the ge engines run a higher angle (hence youll see that most ge engines have a larger cyl head)

[Savant]

i thought i knew a bit about vtec until reading this. I have learnt nothing, but instead become more confused about the matter.

Everyone thinks they know what they are talking about while everyone else says they don't. The ones who look like they know something have written it down so bad that it's just as confusing as a wrong statement.

I feel i have just wasted 15 or so mins reading this thread.

Can someone write a summary post taking into regard all the PROVEN facts (that means no opinions and no "yeah it's right, i just know it is" type stuff) so that no one has to waste as much time as i did reading this crap!!!!!

[barefootbonzai]

Has anyone raced a Corolla Sportivo rated at 140kw? Cuz my cuzin said he did in his Jap Spec B16 EG and beat it easy. I've also race a 20 valve silver top corolla and beat that too. What ever it is that honda is doin, keep up the good work.

[vvtl-i]

Has anyone raced a Corolla Sportivo rated at 140kw? Cuz my cuzin said he did in his Jap Spec B16 EG and beat it easy. I've also race a 20 valve silver top corolla and beat that too. What ever it is that honda is doin, keep up the good work.

wat 1/4mile time do u run, biatch? :D

[Spoon-Accord]

wat 1/4mile time do u run, biatch? :D

lolz.. you just signed up to post bash the poor bugger??
lolz.
i am having fun. keep at it guys..


Ken

[vvtl-i]

lolz.. you just signed up to post bash the poor bugger??
lolz.
i am having fun. keep at it guys..


Ken
hahahaha
barefootbonzai has a very nice car although i reckon the 18s are WAY too big :p
just wondering what kind of 1/4mile would the b16 coupe run.
most if not all the corolla sportivos that i've watched at willowbank run mid to low 15s

[civiceg9]

Has anyone raced a Corolla Sportivo rated at 140kw? Cuz my cuzin said he did in his Jap Spec B16 EG and beat it easy. I've also race a 20 valve silver top corolla and beat that too. What ever it is that honda is doin, keep up the good work.

The gear ratio is not good in the rolla spotivo and celica.
20 value AE111 6 speed will give civics a run for the money
but not alot of ppl in Asia like to race it as it seems to be abit fragile.

Honda built Type R are built like a race car, so most cars in the same category are no match for it. Is even faster then the RX8 around the tracks.

[panda[cRx]]

i thought i knew a bit about vtec until reading this. I have learnt nothing, but instead become more confused about the matter.

Everyone thinks they know what they are talking about while everyone else says they don't. The ones who look like they know something have written it down so bad that it's just as confusing as a wrong statement.

I feel i have just wasted 15 or so mins reading this thread.

Can someone write a summary post taking into regard all the PROVEN facts (that means no opinions and no "yeah it's right, i just know it is" type stuff) so that no one has to waste as much time as i did reading this crap!!!!!

what he said:confused:

[wynode]

i thought i knew a bit about vtec until reading this. I have learnt nothing, but instead become more confused about the matter.

Everyone thinks they know what they are talking about while everyone else says they don't. The ones who look like they know something have written it down so bad that it's just as confusing as a wrong statement.

I feel i have just wasted 15 or so mins reading this thread.

Can someone write a summary post taking into regard all the PROVEN facts (that means no opinions and no "yeah it's right, i just know it is" type stuff) so that no one has to waste as much time as i did reading this crap!!!!!
What are you confused about in regards to VTEC?

You can read this (http://www.ozhonda.com/forum/showthread.php?t=13&highlight=vtec)about VTEC (more reading in the links) if you want to know the basics. If you want more detail, simply reply to that thread.

[JDM.Power]

hey whooaaa that is alot of reading to do..!!
im just saying something so v-tec is much better than a vvt-i an better technology?? right

[Spoon-Accord]

your right there JDM.Power..
Honda spent more time researching into the engines..
especially they made their first VTEC engine like 10-15 years ago..
toyota only started making their version of "VTEC" like 4-5 years ago(just estimating)
think cause they got round selling alot more camrys.. and invested on making their engines diffrent for a change..

anywho's

my 2 cents

Ken

[Peekay34]

Has anyone raced a Corolla Sportivo rated at 140kw? Cuz my cuzin said he did in his Jap Spec B16 EG and beat it easy. I've also race a 20 valve silver top corolla and beat that too. What ever it is that honda is doin, keep up the good work.


I had a Corolla Sportivo before I got the Honda. Mine had 10K spent on it ..Unichipped, Lightened Flywheel, CAI amongst many other things. They are very quick little car for what they are. But they need modding to really perform. They had a ECU recall last year cos they were running under powered, after the recall was much better. Don't under estimate them I have blown some very modified looking Honda Civics and also Integras. only trouble is they don't really start to perform before 6200 Rpm then they go pretty hard. But also there is a lot of Hondas that would blow them away as well..I know so don't start hammering me... I know alot about these cars and what they are capable of . When I had it I totally enjoyed it. Remember they are only a 29K Car + on roads for what they cost I think they are not bad value for a Low price performance car.

The Guy who was driving his Sportivo in your comment above probably did not know how to drive his car. They do have issues with the Gearbox they have shitty Gear Change and it is difficult to change at times. And it takes some skill to keep it in lift whilst changing gears.

But overall now I have the Honda ..quality is far superior.

[Spoon-Accord]

I had a Corolla Sportivo before I got the Honda. Mine had 10K spent on it ..Unichipped, Lightened Flywheel, CAI amongst many other things. They are very quick little car for what they are. But they need modding to really perform. They had a ECU recall last year cos they were running under powered, after the recall was much better. Don't under estimate them I have blown some very modified looking Honda Civics and also Integras. only trouble is they don't really start to perform before 6200 Rpm then they go pretty hard. But also there is a lot of Hondas that would blow them away as well..I know so don't start hammering me... I know alot about these cars and what they are capable of . When I had it I totally enjoyed it. Remember they are only a 29K Car + on roads for what they cost I think they are not bad value for a Low price performance car.

The Guy who was driving his Sportivo in your comment above probably did not know how to drive his car. They do have issues with the Gearbox they have shitty Gear Change and it is difficult to change at times. And it takes some skill to keep it in lift whilst changing gears.

But overall now I have the Honda ..quality is far superior.

:thumbsup: :)

i feel yah dawg!!

[Limbo]

yeah have to admit the Honda's gbox is alot closer and easier to shift compared to the corollas. Yeah the "Blacktop 20v" would give most type rs a run for its money. BUt it only comes with optional LSD and optional 6 speed so they are rare to come by, especially when they are only released in Japan and are usually kept as track cars over there. I've only known of 2 in Aus. You do know they have a Forumla 1 atlantic which races the Spoon engines in the US.

Wynde - Don't know about the lift in the BMW i got those specs from a website. Not all that informed with BMs. But i do know the Toyota system has a lift as well. Similar to the vtec design.

One thing i noted though the Toyotas don't seem to take as much fuel while high revving

[sirvtec]

Vtec kicks ass and would beat the corolla
the best thing to do is get the two cars together and give it a run
and record it and then post it up. so every1 can see.
around the track the civic would kill it as the civics chassis would built good.

[muli]

what about vanos or variocam?

[aaronng]

It's not a matter of whether VTEC or VVTi or VVTLi or (Double) VANOS or Variocam (Plus) is better. Each of them allow you to tune the engine to produce torque at a higher peak while still producing torque at the lower revs, or a wider spread of torque, while maintaining a sufficient amount at high revs.

They are just a means to an end. And in the end, which is more powerful depends on how aggressive the cams are in the engine, the compression ratio and whether it has been lightened, balanced and polished from the factory.

I think the only way to determine which system is better is based on its reliability and how quick and seamless the system can switch between cam profiles and/or timings.

[muli]

having been in a porsche it did have quite alot of grunt at low revs but this might be due to the bigger engine capacity, hows the nsx for low end grunt even though it is a smaller engine than the porsche

[aznsiko]

i definetly would choose VTEC over VVTi not because im a Honda lover but from seeing the performance i beleive that VTEC is better.. about 3 months ago i took on a current model corolla with VVTi.. i drive a teggy LS no VTEC.. its stock with air filter and my cams and timing were tuned by Hannys Performance.. anyways i took on this corolla down parramatta road.. i was amazed as i had him 4 out of 6 times.. take off would be even 2nd i would pull a bit and 3rd pull off.. i found it amazing as i was running a stock clutch that was slipping at the time.. im not sure if it was the driver or the corolla's performance that lacked.. and then i took my mates teggy dc2 VTiR.. and he took me.. 3 out of 4 times.. so you can see.. both 1.8L engines one VVTi and one VTEC.. the VTEC showed better perfomance.. but also got the driver to consider...

GO VTEC!!!!