TECH: Future of VTEC?
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TECH: Future of VTEC?
I found this a nice read from another post recently.
Ive read this article a few time over the last year, and I just keep forgetting this stuff.
The Future
From now onwards, there will no doubt be countless attempts to second-guess at what Honda will do to i-VTEC. There is all likelihood that Honda will implement i-VTEC on its performance engines. The most probable benefiaries will be the Integra and the Civic, the two models which have always been at the forefront to carry Honda's high-performance flag.
At this point, it is important to highlight again that the basic DOHC VTEC system is more than capable of delivering extremely high specific power outputs. i-VTEC is not needed. Witness the 125ps/litre power delivery of the F20C used on the S2000. Again what i-VTEC do allow is for Honda to go for the sky in terms of specific power output but yet still maintaining a good level of mid-range power. Already extremely authoritative reviewers like BEST MOTORing have complained about the lack of a broad mid-range power from for eg the F20C engine. In a tight windy circuit like Tsukuba and Ebisu, the S2000 finds it extremely tough going to overtake the Integra Type-R in 5-lap battles despite having 50ps or 25% more power. Watching the 'battle' brings one point painfully clear. There is a dire need of power from the F20C below 6000rpm. Every time the S2000 sneaks up behind the ITR, it fails to engage in a good overtaking move because the power from the F20C is surprisingly insufficient. The reason for this is because DOHC VTEC makes do with merging two distinct power curves. To get the extreme power levels of the F20C, the wild cams' power curve are so narrow that there is effectively a big hole in the composite power curve below 6000rpm. What i-VTEC can do to this situation is to allow fine-tuning of the power curve, to broaden it, by varying valve opening overlap. Thus this will restore a lot of mid-range power to super-high-output DOHC VTEC engines allowing Honda, if they so desire, to go for even higher specific outputs without too much of a sacrifice to mid-range power.
For the moment the 2.0l DOHC i-VTEC engine on the STREAM delivers 154ps and revs to around 6500rpm. This is relatively low-tech as far as Honda's DOHC VTEC engines go. There must be a lot of scary DOHC i-VTEC engines on Honda's design boards at the moment. TOVA readers who are interested to look at what's in the rumour mills are encouraged to visit TOVA's main-site, the Temple of VTEC for one of the best source of future Honda models information on the net.
However, readers who prefers to only read about solid facts can rest assured that once the expected super-high-powered DOHC i-VTEC engine comes out, TOVA will be the first to highlight it, just as we are now the first to explain to you what i-VTEC is all about.
WongKN
November 2000
© Temple of VTEC Asia
Source: http://asia.vtec.net/article/ivtec/
Ive read this article a few time over the last year, and I just keep forgetting this stuff.
The Future
From now onwards, there will no doubt be countless attempts to second-guess at what Honda will do to i-VTEC. There is all likelihood that Honda will implement i-VTEC on its performance engines. The most probable benefiaries will be the Integra and the Civic, the two models which have always been at the forefront to carry Honda's high-performance flag.
At this point, it is important to highlight again that the basic DOHC VTEC system is more than capable of delivering extremely high specific power outputs. i-VTEC is not needed. Witness the 125ps/litre power delivery of the F20C used on the S2000. Again what i-VTEC do allow is for Honda to go for the sky in terms of specific power output but yet still maintaining a good level of mid-range power. Already extremely authoritative reviewers like BEST MOTORing have complained about the lack of a broad mid-range power from for eg the F20C engine. In a tight windy circuit like Tsukuba and Ebisu, the S2000 finds it extremely tough going to overtake the Integra Type-R in 5-lap battles despite having 50ps or 25% more power. Watching the 'battle' brings one point painfully clear. There is a dire need of power from the F20C below 6000rpm. Every time the S2000 sneaks up behind the ITR, it fails to engage in a good overtaking move because the power from the F20C is surprisingly insufficient. The reason for this is because DOHC VTEC makes do with merging two distinct power curves. To get the extreme power levels of the F20C, the wild cams' power curve are so narrow that there is effectively a big hole in the composite power curve below 6000rpm. What i-VTEC can do to this situation is to allow fine-tuning of the power curve, to broaden it, by varying valve opening overlap. Thus this will restore a lot of mid-range power to super-high-output DOHC VTEC engines allowing Honda, if they so desire, to go for even higher specific outputs without too much of a sacrifice to mid-range power.
For the moment the 2.0l DOHC i-VTEC engine on the STREAM delivers 154ps and revs to around 6500rpm. This is relatively low-tech as far as Honda's DOHC VTEC engines go. There must be a lot of scary DOHC i-VTEC engines on Honda's design boards at the moment. TOVA readers who are interested to look at what's in the rumour mills are encouraged to visit TOVA's main-site, the Temple of VTEC for one of the best source of future Honda models information on the net.
However, readers who prefers to only read about solid facts can rest assured that once the expected super-high-powered DOHC i-VTEC engine comes out, TOVA will be the first to highlight it, just as we are now the first to explain to you what i-VTEC is all about.
WongKN
November 2000
© Temple of VTEC Asia
Source: http://asia.vtec.net/article/ivtec/
i can't wait to see someone come out with some aggressive i-VTEC cams dropped in a Type-S. that'll be sick. The addition of VTC is the only difference between VTEC and i-VTEC. But it's this difference that allows for more midrange power.
I like those stickers that say "Vtec sucks" anyone else see those ? I just think there funny. Sorry this is off topic sorta.
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WTB:A clean 90-91 civic hatchback. Red or black or white in color. Good exterior. Looking to spend around $2,000.
WTB:A clean 90-91 civic hatchback. Red or black or white in color. Good exterior. Looking to spend around $2,000.