# VTEC..........(forced induction?)



## wishIwasVR6 (Apr 2, 2002)

Is a VTEC some sort of forced induction?


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## kaninchen (Mar 28, 2001)

*Re: VTEC..........(forced induction?) (wishIwasVR6)*

your funny... you know your funny right?


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## wishIwasVR6 (Apr 2, 2002)

*Re: VTEC..........(forced induction?) (kaninchen)*

I know it ain't forced induction.......I had no other place to post this question. Can someone explain to my slow ass what it is?


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## 2nutz (Sep 13, 2001)

*Re: VTEC..........(forced induction?) (wishIwasVR6)*

Valve or variable timing electronic controller. i think it slides the cam sideways to some bigger lobs and thats why they get so freaking loud when they hit about 4k.


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## turbo8v (Feb 2, 2001)

*Re: VTEC..........(forced induction?) (2nutz)*

vetec slides a row of bigger rockers into place. This inturn opend the valves ad a different ratio than befor. while it is a good system it is only yht start of variable valve timing. It inly adjusts once through the whole power band. The new 7 series bmw adjusts infinate # of times That is an awsome system but it comes with a heavy price tag.
And to answer your ? it is in no way a form of forced induction it is just a good means of normal asperation.


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## vdubturbo (Aug 31, 2001)

*Re: VTEC..........(forced induction?) (turbo8v)*

quote:[HR][/HR]The new 7 series bmw adjusts infinate # of times That is an awsome system but it comes with a heavy price tag[HR][/HR]​Funny, Infiniti had infinite VVT on the Q45 starting in '89. It had an electric steppermotor on the front of the cam that advanced the cam with respect tot he chain. Pretty neat. Only on one set of valves though. I think the BMW system is based on oil pressure. (At least the old ones were)


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## JacksonYo! (Mar 12, 2002)

*Re: VTEC..........(forced induction?) (turbo8v)*

This is how a cam works.








"VTEC (which stands for Variable Valve Timing and Lift Electronic Control) is an electronic and mechanical system in some Honda engines that allows the engine to effectively have multiple camshafts. As the engine moves into different RPM ranges, the engine's computer can activate alternate lobes on the camshaft and change the cam's timing. In this way the engine gets the best features of low-speed and high-speed camshafts in the same engine."
I am sure the bmw 7 series has mulitple lift engagements making it smoother for the consumer buying the car. 


[Modified by JacksonYo!, 10:52 PM 4-17-2002]


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## scolen2 (Jan 16, 2002)

*Re: VTEC..........(forced induction?) (wishIwasVR6)*

the new Honda VFR800 has a Vtech type engine in it, but it came with a price, the old Gear driven cams are gone :-(


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## GTibunny16v (Aug 12, 2001)

*Re: VTEC..........(forced induction?) (JacksonYo!)*

VTEC on a B seiries motors. These are in SI's and GSR's. With this style VTEC, you have 3 cam lobes. 2 small lobes w/ a larger lobe in the center. The 2 smaller lobes move rocker arms to open the valves. When VTEC is engaged the ECU opens an oil solenoid, which pushes a rod to lock the 2 small lobe rocker arms to a third center mounted rocker arm. Now that the arms are locked together the bigger lobe now opens both valves. So now you have a bigger cam profile. 
The new i-VTEC has the same priciple but has variable cam timing also. This increases low down torque. Something the old B series motors were lacking.
The BMW M3 has the same style system as i-VTEC. Also, the 5-7 series has variable cam timing. Toyotas VVT-i is the same as i-VTEC. The chevy Trailblazer has variable cam timing also. Hope this clears it up for everyone.


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## killa (Nov 26, 2000)

*Re: VTEC..........(forced induction?) (vdubturbo)*

quote:[HR][/HR]The new 7 series bmw adjusts infinate # of times That is an awsome system but it comes with a heavy price tag
Funny, Infiniti had infinite VVT on the Q45 starting in '89. It had an electric steppermotor on the front of the cam that advanced the cam with respect tot he chain. Pretty neat. Only on one set of valves though. I think the BMW system is based on oil pressure. (At least the old ones were)







[HR][/HR]​yeah, but nissan only had variable cam timing, it just retarded the cam timing as rpm went up, it had nothing to do with lobes. The z32 300zx's also had that feature, the newest ones anyway.


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## Toda Party (Apr 14, 2002)

*Re: VTEC..........(forced induction?) (GTibunny16v)*

quote:[HR][/HR]VTEC on a B seiries motors. These are in SI's and GSR's. With this style VTEC, you have 3 cam lobes. 2 small lobes w/ a larger lobe in the center. The 2 smaller lobes move rocker arms to open the valves. When VTEC is engaged the ECU opens an oil solenoid, which pushes a rod to lock the 2 small lobe rocker arms to a third center mounted rocker arm. Now that the arms are locked together the bigger lobe now opens both valves. So now you have a bigger cam profile. 
The new i-VTEC has the same priciple but has variable cam timing also. This increases low down torque. Something the old B series motors were lacking.
The BMW M3 has the same style system as i-VTEC. Also, the 5-7 series has variable cam timing. Toyotas VVT-i is the same as i-VTEC. The chevy Trailblazer has variable cam timing also. Hope this clears it up for everyone.[HR][/HR]​ http://****************.com/smile/emthup.gif


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## speed51133 (Feb 18, 2000)

*Re: VTEC..........(forced induction?) (Toda Party)*

just wait until you start seeing valves opening and closing without the use of a cam, and without any springs being used......








i have a working model


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## scolen2 (Jan 16, 2002)

*Re: VTEC..........(forced induction?) (speed51133)*

The Formula 1 guys are thinking in 5 years this might be working, but for now it's beyond there grasp. But think about this for a minute... 3L NA engines producing 850+ HP at 18,000 RPM. Now add electro controled valves along with Electro controled injection and spark timing, 19,000PRM with perfect touque curbes, maybe even 1000HP! Remember, formula one cars did use to put out 1400HP with 1.5 L engines, but that was thanks to turbo...
Oh yeah, don't forget the traction control and automactic sequencle gear boxes...$$$$


[Modified by scolen2, 11:39 PM 4-18-2002]


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## Me109 (Mar 28, 2000)

*Re: VTEC..........(forced induction?) (speed51133)*

quote:[HR][/HR]just wait until you start seeing valves opening and closing without the use of a cam, and without any springs being used......








i have a working model[HR][/HR]​How's it work? Magnets?


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## NorthDakota2.0 (Nov 6, 2001)

*Re: VTEC..........(forced induction?) (speed51133)*

quote:[HR][/HR]...i have a working model[HR][/HR]​Thats really cool. Did you use some kind of solenoids?


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## speed51133 (Feb 18, 2000)

*Re: VTEC..........(forced induction?) (NorthDakota2.0)*

guys, id love to share details, but its my senior design project, and we are looking at getting it patented, so until its done, no details.
BUT, it works.
lets put it this way, its a VERY simple design.


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## jazzpur (Dec 27, 2001)

*Re: VTEC..........(forced induction?) (speed51133)*

hey speed...few more hints


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## nigel (Jan 3, 2001)

*Re: VTEC..........(forced induction?) (jazzpur)*

Try this site it has some interesting stuff http://www.coatesengine.com/eGallery/index.html 










[Modified by nigel, 9:39 PM 4-18-2002]


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## speed51133 (Feb 18, 2000)

*Re: VTEC..........(forced induction?) (nigel)*

son of a bitch...
its not the same as I have, but its the same basic deal. I guess its not as revolutionary as I thought








we have a working prototype for a 1 cylendar Briggs and Stratton 5hp motor. My buddy and I are talking about building a working model for an old 1.8L 8V block he has.
i did not think anyone would care in this forum, but i guess ill post pics of it. I did not know it had already been done. I like my design better though!


[Modified by speed51133, 11:52 PM 4-18-2002]


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## a2vwnick (Oct 25, 2000)

*Re: VTEC..........(forced induction?) (wishIwasVR6)*

quote:[HR][/HR]Is a VTEC some sort of forced induction?[HR][/HR]​Your KILLIN me Smalls!!!!


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## nigel (Jan 3, 2001)

*Re: VTEC..........(forced induction?) (speed51133)*

Sorry didn't mean to burst the bubble Speedo
the rotary valve design is difficult to seal properly but has a lot of potential if that flaw can be overcome with materials advancement or improved design


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## rocco2nr (Aug 24, 2000)

*Re: VTEC..........(forced induction?) (speed51133)*

heh good ol' flat head briggs? i used to race modified five horse briggs and stratton (karts).


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## turbo8vjetta (Oct 10, 2001)

*Re: VTEC..........(forced induction?) (rocco2nr)*

That rotary design has been out for some time now.Apparently they do not need to be lubed neither.


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## Metallitubby (Aug 20, 2001)

*Re: VTEC..........(forced induction?) (2nutz)*

quote:[HR][/HR]Valve or variable timing electronic controller. i think it slides the cam sideways to some bigger lobs and thats why they get so freaking loud when they hit about 4k. [HR][/HR]​well..... ever notice the SOHC cars dont make the louder noise when VTEC engages? This is because the DOHC VTEC cars have the IAB ( Intake Air Bypass ) which is a resonancy tuned length intake manifold, just like the Schrick manifold.
When, as stated above the oil pressure rises ( i.e along w/ engine RPMs ), the valves/rocker arms are locked onto a higher lift camshaft lobe producing both good low end driveability and good high end reving power. 
Add the IAB/Variable length intake used on old SE Accords, Preludes ( H23 ), and some other engines, and the roar made when switching lobes is MUCH louder due to the length of the intake manifold changing.
sheesh, If anyone wants Honda training films, lemme know cause I have the whole library........


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## TurboABA (Mar 3, 2002)

*Re: VTEC..........(forced induction?) (vdubturbo)*

Actuallly the BMW design is nothing like the rest of this ancient stuff. No extra lobes or anything. They use a special shape rocker/follower with a funky foot design and cams that changes their rotational axies.


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## Sandlock (Aug 10, 2001)

*Re: VTEC..........(forced induction?) (nigel)*

Yea speed, you may still have a window of opportunity to shine, so dont go rollin that beautiful bean footage yet, you may be giving someone else a head start. That sounds pretty sweet tho, especially since you didnt have someone elses influence on development http://****************.com/smile/emthup.gif


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## GTibunny16v (Aug 12, 2001)

*Re: VTEC..........(forced induction?) (Metallitubby)*

quote:[HR][/HR]Valve or variable timing electronic controller. i think it slides the cam sideways to some bigger lobs and thats why they get so freaking loud when they hit about 4k. 
well..... ever notice the SOHC cars dont make the louder noise when VTEC engages? This is because the DOHC VTEC cars have the IAB ( Intake Air Bypass ) which is a resonancy tuned length intake manifold, just like the Schrick manifold.
When, as stated above the oil pressure rises ( i.e along w/ engine RPMs ), the valves/rocker arms are locked onto a higher lift camshaft lobe producing both good low end driveability and good high end reving power. 
Add the IAB/Variable length intake used on old SE Accords, Preludes ( H23 ), and some other engines, and the roar made when switching lobes is MUCH louder due to the length of the intake manifold changing.
sheesh, If anyone wants Honda training films, lemme know cause I have the whole library........[HR][/HR]​
B16[SI's]B17 [2nd gen GSR] (im not sure on his one) B18C5 [ITR] dont use a variable length intake. I think the GSR B18 is the only B seires motor that uses the VLT


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## Metallitubby (Aug 20, 2001)

*Re: VTEC..........(forced induction?) (GTibunny16v)*

quote:[HR][/HR]
B16[SI's]B17 [2nd gen GSR] (im not sure on his one) B18C5 [ITR] dont use a variable length intake. I think the GSR B18 is the only B seires motor that uses the VLT[HR][/HR]​notice I posted that older Accord SE's and Prelude DOHC's are equipped. There are other cars equipped with IAB, but are not stated.


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## VWsounds (Dec 3, 2000)

*Re: VTEC..........(forced induction?) (Metallitubby)*

I remember reading an article somewhere stating that if you drove your civic si around the streets with vtec constantly engaged (IE 5500rpm< I think) you would have the same fuell efficiency as a 5L mustang. It made me giggle.


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## GTibunny16v (Aug 12, 2001)

*Re: VTEC..........(forced induction?) (Metallitubby)*

I wasnt disagreeing with you, i was just stating what B series motors came equipped with that option.


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