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VVT-i VS. VTEC ?...

17128 Views 110 Replies 28 Participants Last post by  vinceprince
which engine is better VVT-i VS. VTEC?
also whats the difference between V6 and I6? IS300 I6 better?

thank you!
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At first your remark pissed me off because my parents are from Japan. But looking at this list,

it shows the CD was the only noteworthy Japanese invention in the 19th and 20th century. I think the Japanese are perfectionists and while the term "failure is not an option" has turned into a cheesy cliche in America, I think it still holds true in some parts of Japan. The Samurai sword is considered the best crafted sword in the world. Also the old saying "necesisty is the mother of invention" is only partly true.

Originally posted by HIBBoyScott:
That is very true. The Japs never invented nothing. They just take whatever exists and make it a lot better. Although I guess now they are starting to invent stuff, but when you look at so many things that you relate to the best coming from a Jap company...all of it was just an improvement on something that already existed. I think the Japs are super inventive because of their environment. They live on a hazardous piece of real estate and are over crowded like mad. So they invent stuff to improve their situation. Small stereos that play as good as huge, earthquake proof buildings, etc.
Why do I get a funny feeling that you don't know what you're talking about? Cites please.

Originally posted by IS300GTE:
Honda was neither the inventer, nor the first to experiment with variable valve timing.

VVTI is better than VTEC, because it's adjustment period is throughout the entire rpm band, instead of around 4500(approx), like when hondas VTEC will kick in. flexibility for optimum performance is the difference, toyota has it, honda does not.
I don't care if you are from Mars. What you said was wrong and I made a correction. No hard feelings.

Originally posted by HIBBoyScott:
Kota, you shouldn't be taking offense at any comment anyway.
HIB I'm talking about the your bs claim "the Japanese people don't invent". If you don't know what you're talking about, then don't act like you know. Go to a library for christ sake.

[This message has been edited by Chiphead (edited November 11, 2000).]

Under select Database, choose "all"
Under term 1 type in "jp"
Under Field 1 choose "Inventor Country"
Click on "Search"

[This message has been edited by Chiphead (edited November 11, 2000).]

It says Japanese scientists are encouraged to research marketable ideas. So yes they do a lot of improving, but there is no denying that they *do* invent.
Thanks for debating with me. You are right. I was wrong. Good night.
Insulting me will only harm your credibitly. Now about that cite. I'm still waiting.
VTEC does not "kick in" as you put it. It is constantly there. You are right about Toyota's infinately variable valve timing. Honda has 3 profiles.

On paper the VVTL-i is better, but real world when you compare the Acura GS-R to the Celica GTS, they perform about the same.

Celica GTS

Acura Integra GS-R

[This message has been edited by Chiphead (edited November 13, 2000).]
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When I say "VTEC is constantly there", I mean it's not something that can be turned off. It's built into the engine. The point at where it changes cam lobes has nothing to do with the fact that VTEC is "turned on". VTEC optimizes it's cam lobes according to the rpm of the engine. The word "variable" is pointing to the "variable" nature of the timing, not the on/off nature. Honda should use the word "bipolar" or some such word if what you said was the case. I quote from Honda: "VTEC optimizes the combustion chamber's breathing and efficiency at LOW and HIGH engine speeds."

Originally posted by IS300GTE:

it does "kick in", actually. the vtec becomes operational around 4500 rpm.
Brad are you always this annoying when someone questions your credibility? I must have struck a nerve
I still maintain that VTEC does not kick in. So you can feel a push at 4500rpm? And how does that makes you an expert on VTEC? Sorry to burst your inflated ego, but information culled from a reliable sources (eg manufacturer) has more crediblilty than you.

Originally posted by IS300GTE:
"It is better for people to think you are a fool, then for you to open your mouth and remove ALL doubt."
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My credibility is not in question here since I'm quoting Honda. Stop being a pompous azz and just read the cites I gave you.

"The VTEC system, first pioneered in the NSX, alters valve timing and lift to boost LOW END TORQUE and high end horsepower."

"With VTEC, the engine delivers ample LOW-RPM TORQUE and high-rpm power without sacrificing either. But best of all, no matter where you are on the rpm band, all Acura engines deliver the kind of smoothness normally associated with gyroscopes."

VTEC refers to the whole system, not just the higher rpm profile.

"Thus, normal street engines have little ower in the upper rpm's, and race cars with high rpm power have little low-end torque. The VTEC was invented in order to compliment both."

I know your attention span is limited, but please read the cites this time.
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