It's not even close to even being the same principle though. Honda uses an extra, high lift cam lobe and a rocker that can be de-coupled. VAG simply shifts the tension on the cam chain,which either slightly advances or retards both cams the same amount. VTEC varies both timing and lift, sometimes continuously, while VAG VVT just varies timing in 2 steps.

 

Honda has turbochargers on all of their IRL cars (they were the sole supplier of IRL engines in and around 2009), so they know the technology very well.

What I would love to see, is my B5 with a turbo that spools up quickly, for low end power and VVT (with a high red line) for top end power, while still maintaining a smaller displacement engine. That would be the perfect combination of excellent fuel economy, or huge power output (when compared to engine size). Both options available to you at a moments notice. That's just my ideal opinion though.

I understand your point, but see above for my point.

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the vvt in your audi is only used for emissions purposes from the factory. I don't know if it is a recent development or not, but the vvt in an audi can be manipulated to work outside startup, i.e. during high revs. I would love to look into it for future purposes because coupled with a set of cams, you are talking huge gains, like 100+ hp, near the top of the rev range.

here's some insight http://forums.vwvortex.com/showthrea...-to-make-power and check out this graph from an s4. 034 is using vvt, awe is not. quite impressive if you ask me

 

Not quite, I've looked at the VVT advance maps and it's used for 2 things: emissions like you said, and for a little extra torque up at low/mid revs. There's advance at low throttle low-rpm and mid to high throttle and mid-rpm. There's a couple of discussions on this at nefmoto, and the guys there know more on the subject than everyone in this thread combined.

 

the guys on nefmoto do know their ****. but yeah, audi vvt isn't like vtec in that it isnt actuated high in the rev range in its stock form. it sucks that it cant be more variable in an audi, its either on or off.
I haven't done that much research on audi vvt, but it seems like its simply on or off by sending 12v to the solenoid. if that voltage could be regulated somehow maybe it could be of even more benefit. put this is about the scope of my knowledge with vvt

 

You bring up an interesting point about trying to vary the VVT angle, but unfortunately it's not feasible. People have said that the response time is pretty slow, it takes a couple of revolutions for it to change state. It also takes quite a bit of current (evident by the fact that it has it's own fuse directly off the ECU relay), so a PWM system is pretty much out of the question. Even if you do get past this somehow, there really isn't much value added since all you'll be doing is making the transition smoother, 90% of drivers probably wouldn't even feel a difference and dyno plots would be nearly identical.

 

Now that's what I'm talking about!

Thanks!

 

Hi there. I see you speak about different engines etc, and maybe someone can help me out.

I have an Audi a4 b5 1.8t Quattro, 96 model. I went to my local tuningshop(not many of them in Norway...), and he told me there wasnt much to do with the engine, since the "brain" couldnt handle alot more than stock power. Its chipped to about 190hp now, and I wonder: Can i get more hp out of my engine without alot of work, or are my local tuner right?

Best regards Stephan, Norway

 

190hp is about what these engines can do without a turbo upgrade. you might be able to squeeze a little more power out here and there, but it wont amount to much and it wont be worth the money in my opinion.

 

Yeah, but this guy told me even if i upgrade the turbo, the engine cant handle any more? Was wondering about a K04, or a small GT. Want to get about 230-250HP.