VTEC vs VVVL-i

[JD@af]

I've read about the Porsche variable valve timing as well. I forget the specfic details of the mechanics of the system, but indeed it engages a mechanism that increases duration and lift of the cam profile at certain rpms. I was not aware that this system was able to be initiated without a necessary rpm range; however, I believe that Honda's VTEC system can work in this way as well, since ths system is governed in its operation by four controlling factors, including rpm and throttle position.

[texan]

read the bottom of this page guys...
http://www.fortunecity.com/silversto...ine/vvt_31.htm

It explains how the Variocam Plus system is a two stage setup when it comes to lift and duration levels, while the cam phasing portion is continous. It's damn near identical to VTEC-i, except that the engagement mechanism is significantly more compact and ingenius (it had better be, since it's ten years newer in design).

[JD@af]

Great, I'll check out the link you supplied.

Much obliged, sir

[gang$tarr]

yeah i know the rsx is gunna replace the prelude & integra, i posted that a long time ago, before i knew that

the civic hatchback isn't gunna have vtec, the civic Type R will

[Moppie]

Originally posted by VTEC V6
.........but it can actuate anytime not like honda's fixed timing as in 5500rpm on a civic

I believe only the SOHC VTEC's are restricted to a fixed crossover point in the RPM band. My DOHC B16a however is able to change at anywhere from 4,800rpm to 5,300rpm depending on road speed, engine speed and throttle position. Very handy if you dont want a flat spot when driving hard out of a corner, or when crusing at highish speed while still getting the best available economy.



I believe Ferrai has a simlar system, that uses a sloped lobe, from high lift to low lift its a smoth transition and the camis slid sideways accross the top of the valve. http://www.howstuffworks.com/camshaft3.htm

[JD@af]

WOW! Thanks for the link! I was under the impression that Ferrari did not use variable valve timing to make their high horsepower, high rom screaming engines. I guess I was misinformed.....

[Jay!]

Yeah, that www.howstuffworks.com site is great!!! I read stuff on there for an hour, and put it in my IEFavorites so I'll remember to go back later.

Thanks for posting it.

Dude, you're really cleaning up around here. (No pun intended.)

[Moppie]

Originally posted by JD@af
WOW! Thanks for the link! I was under the impression that Ferrari did not use variable valve timing to make their high horsepower, high rom screaming engines. I guess I was misinformed.....

It was shown to me by someone else in another (lesser) forum. I certainly didnt know about it either, looks like Ferrari were keeping it pretty quite, probobly didnt want people thinking they were no better than a Honda! :silly2:


Silver S2000
Thanks, (and there is some meaning in that pun) but Look to Texan and some of the others (I dont know many of you yet) for the real Tech advice. I only know the basics, and what Iv learnt from others.

[evil_elmo]

what cars does the VVTL-i engine come in?

[Jay!]

I know it's on the Celica, the ECHO, and almost all the Lexuses. Maybe the MR2 Spyder, not sure... what else?

[Moppie]

Originally posted by Silver S2000
I know it's on the Celica, the ECHO, and almost all the Lexuses. Maybe the MR2 Spyder, not sure... what else?

The Celica is the only model to have the VVTL which is the two cam lobes, all the others only have the vraible cam timing, which is something Toyota have been playing with since '91 with a 20V version of the old 4agze. There was talk of a super fast VVTL-i powered MRS but it never seems to have happened. I think Toyota leaned on the side of caution, 180hp in a such a light little car, would be deadly. However since it uses the same basic engine as the Celica, an engine swap is quite feasible.

[Integra-F20C]

hey hey hey!..look who's back in town!..

well anyway guys, form my experice of test drigin a stock JDM Integra SiR and a stock Celica SS2...which has same enggine but more hp thenn the usdm GTS..

let me tell u what..at first when i drove it..i thought...that celica should be much torquey then the B18C teg at low rpm...so i stepped on it..but now...it was abt the same as a B18C jdm Teg..so i waited until it pulled over 5500rpm..ok..u can't feel no explosiveness from that car stock for stock..all i can say is..whatever that VVTi-L says it should do, it's nto doing so, it accelerates like a freaking pregnant woman at high rpm's not as explosive as honda if even comapred to a 1.6L B16A...and still restsless at low rpm's.

so at the end, I'd say, come'on TOYOTA!..u can't even god damn beat a B18C Teg made 7-8 years back in technology and perfroamnce!..
and then...well..after i finished test driving, I opened the hood, and all i found out was.."SH*T!..how in da hell can i mod this thing?!"
the engine bay was smaller and tighter then a fat woman with extra small shirt, and even changing the intake into a cone was pretty hard i'd say..and as for headers...many of u know..that just changing headers for celica is a damn big job, so yea..geez..7-8 years newer technology then the B18C teg, and it still performance wise, can't beat sh*t..but the onyl good thing i can say is, it's prettty comfortable inside...but not a car that u can make it fast, easily..gotta have lot's a cash!.

but yea..just my 0.2 cents..

[F20C]

Hey Integra how did you manage to put F20C into your car?

[Integra-F20C]

Originally posted by F20C
Hey Integra how did you manage to put F20C into your car?

haha..sorry...the answer to ur question is..I can't and i don't have that much $$$..and even if i did..i won't bother tryign to put a F20C in my car..haha..it's just a nick name i used 2-3 years ago so yea...that time i was stupid and thought i wanted to fit one but as time passed i found out the whole engine spinned the other way round which therefore, if i wanted to fit it, my car could only have one gear going forward and 5 gear going back..

so uhh..yea....

[Jay!]

Originally posted by Integra-F20C
...my car could only have one gear going forward and 5 gear going back..

so uhh..yea....

Hahahaha!!! :cwn27: :hehehe: