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