Bmw Has M...

[4evrwyntr]

What makes a Honda V-Tec different than other Honda engines? I know this sounds like a newbie question, but I am new to the car tech thing. Specs, qualities, intelligence, what makes a v-tec?

[bmwcrazy]

V-TEC is just a part that is added on to the engine. It controls the valve timing. It is similar to BMW's VANOs system.

[4evrwyntr]

A-ha! It is how I suspected. Any more details?

[htp.bmw]

some honda drivers at my high school think there honda has vtech and put the stickers on their car but they dont really have it...

[CiscoKid]

vtech controls the intake timing, along with the VANOs System.

It is the same engine, the only differnance is the variable valve timing.

[4evrwyntr]

Thanks. I find it interesting that two of the world most advanced engine makers use similar systems. Interesting.

[ILiveToRide]

vtec and VANOS doesn't work the same way.

The VANOS system twists the camshaft in relation to the crankshaft, providing variable valve timing.

vtec engines have camshafts with double sets of cam lobes. When it shifts lobes it changes both timing and lift height. It's not very variable since it only has two "setups". Hondas patent ran out recently, Toyotas VVT-i is basically a copy of vtec.

BMW uses VANOS in combination with valvetronic to achive both variable cam timing and lift.

[dutchbmw]

The VANOS system works in the whole engine rpm range, and you have torque present whole the way up. VTEC is more like a 'turbo'; at ~4700 rpm it kicks in.

[4evrwyntr]

Cool. So single VANOS and the limited V-Tec Work on intake, but what about double VANOS (a la eurospec e36 m3)? That's intake and exhaust, right? What are the other companies' versions of variable valve timing called?

[ILiveToRide]

Originally posted by 4evrwyntr@Apr 12 2005, 03:15 PM
Cool. So single VANOS and the limited V-Tec Work on intake, but what about double VANOS (a la eurospec e36 m3)? That's intake and exhaust, right? What are the other companies' versions of variable valve timing called?

[snapback]330718[/snapback]

I'm not sure if vtec engines only have variable intake timing, think it is both.

And yes double vanos is both intake and exhaust cam, came first in the M52 (in 95 in 328i, 323i andn 320i euro models at least) and 96 in euro spec M3.

Not sure what all makers call them though but they all have it.
Hyundai calls it CVVT.
Think Ford uses TVC
Toyota VVT
etc.

Someone can fill in...

[24valve]

Originally posted by ILiveToRide+Apr 12 2005, 04:56 PM--><div class='quotetop'>QUOTE(ILiveToRide @ Apr 12 2005, 04:56 PM)</div><div class='quotemain'><!--QuoteBegin-4evrwyntr@Apr 12 2005, 03:15 PM
Cool.* So single VANOS and the limited V-Tec Work on intake, but what about double VANOS (a la eurospec e36 m3)?* That's intake and exhaust, right?* What are the other companies' versions of variable valve timing called?

[snapback]330718[/snapback]

I'm not sure if vtec engines only have variable intake timing, think it is both.

And yes double vanos is both intake and exhaust cam, came first in the M52 (in 95 in 328i, 323i andn 320i euro models at least) and 96 in euro spec M3.

Not sure what all makers call them though but they all have it.
Hyundai calls it CVVT.
Think Ford uses TVC
Toyota VVT
etc.

Someone can fill in...

[snapback]331074[/snapback]

[/b][/quote]

Porsche had variable valve timing from 1982 on with the 2.5L 8V 944 engine, but I don't think they had a special name or acronym for it. MG also uses the terms VVT and VVTi.

[4evrwyntr]

Any difference between the two (WT vs. WTi)?
And I know, lots of questions, but I AM rather new to the whole car thing (only really got interested after doing some information gathering on my now currently owned bmw pending further monthly installments)...
What benefits does variable valve timing give (number-wise)? I can guess it also depends on the kind of VVT (like porsche's vs. the V-Tec), but is the difference noticeable?
Seeing that the last two cars I drove had VANOS, I'm not sure if I could tell the difference (1995 had VANOS, right?).

[24valve]

Originally posted by 4evrwyntr@Apr 19 2005, 11:00 AM
Any difference between the two (WT vs. WTi)?
And I know, lots of questions, but I AM rather new to the whole car thing (only really got interested after doing some information gathering on my now currently owned bmw pending further monthly installments)...
What benefits does variable valve timing give (number-wise)? I can guess it also depends on the kind of VVT (like porsche's vs. the V-Tec), but is the difference noticeable?
Seeing that the last two cars I drove had VANOS, I'm not sure if I could tell the difference (1995 had VANOS, right?).

[snapback]334792[/snapback]

VVTi stands for "Variable Valve Timing, intelligent," implying a more advanced timing system.

Yeah, 1995 had VANOS, I think they upgraded to double VANOS in 1996 but I could be wrong. Variable valve timing enables changing camshaft lift and duration so that the engine can better tailor itself to allow higher levels of power and efficiency over the rpm range. Imaginably, this results in a horsepower increase because the variable timing allows more fuel in and allows the engine to breathe better when it needs it.

From my experience, VANOS is quite different from VTEC because Honda's system provides a noticable impact when it kicks in. While you're never absolutely sure when VANOS is kicking in, when VTEC in a respectable engine employs, you'll know it. In my friend's RSX type-S, with a 200hp inline four, VTEC kicks in at about 6500rpm (give or take), and when it does, it screams like a banshee. Hope all that helps, it's class time.

[4evrwyntr]

Cool, that's just how I thought it would work. Sometimes, though, when I put that engine to work, I can imagine a woosh and airy sound (different than normal) from my engine throughout it's torque plateau. Maybe it's just wishful thinking.

[triggrhaapi]

Double VANOS didn't grace the US until the E46. Also, single VANOS is a 3 step variable valve timing system, not the infinitely variable system like double VANOS.