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.
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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.
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
6 speed gearboxes are nice tho.
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
you didn't bother reading the other 6 pages did you. :|
try to put it simple as alot of people dont know what they are talking about
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.
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?Quote:
Originally Posted by Limbo
Also I believe Vario cam only changes cam timing whereas variocam+ chagnes valve lift.
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
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..
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)
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!!!!!
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? :DQuote:
Originally Posted by barefootbonzai
lolz.. you just signed up to post bash the poor bugger??Quote:
Originally Posted by vvtl-i
lolz.
i am having fun. keep at it guys..
Ken
hahahahaQuote:
Originally Posted by Spoon-Accord
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
The gear ratio is not good in the rolla spotivo and celica.Quote:
Originally Posted by barefootbonzai
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.
what he said:confused:Quote:
Originally Posted by Savant
What are you confused about in regards to VTEC?Quote:
Originally Posted by Savant
You can read this about VTEC (more reading in the links) if you want to know the basics. If you want more detail, simply reply to that thread.
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
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
Quote:
Originally Posted by barefootbonzai
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: :)Quote:
Originally Posted by Peekay34
i feel yah dawg!!
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
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.
what about vanos or variocam?
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.
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
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!!!!