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Whatever happened to Advanced VTEC?

mike.h

mike.h

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1,797
Late 2005 Honda requested a US patent for "Advanced VTEC" allowing infinite variation of valve lift rather than the high/low we have at present.

It's now 11 years on from that and still no aVTEC. Anyone heard/seen anything interesting about this?

The original article I remember seeing it was on Temple of VTEC. And the associated patent at the USPTO.

Even Manolis Pattakos created something conceptually similar many moons ago. http://www.pattakon.com/pattakonRoller.htm

Maybe the concept works but wear was uneven, or the market changed. Or maybe Honda just lost their will... hard to say.

Does anyone know anything about the fate of this design?
 
I had wondered that, but 3-stage VTEC was an economy design, and if the valves in aVTEC could be engineered to run in an almost-closed configuration then this could run as a throttlebodyless design, elminating pumping losses caused by the throttle plate. Kinda like Valvetronic or Fiat's Multiair, but simpler.
 
Honda threw in the towel and bolted a turbocharger to their performance engines. Vtec is dead.
 
This does make you wonder though, if emission regs never got in the way could Honda have made a n/a Vtec engine to compete with what is out there today?
something similar to a k24 build maybe.


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From the wikipedia page on Fiat's MultiAir engine:

the 1.4 TB engine, without MultiAir, can produce 153 hp and 230 N·m (170 lb·ft) whilst using 6.5 litres per 100 kilometres (43 mpg‑imp; 36 mpg‑US). With MultiAir, the same engine develops 168 hp and 250 N·m (180 lb·ft), while consuming 6.0 L/100 km (47 mpg‑imp; 39 mpg‑US)
Click to expand...

I'd expect something similar to that, so about 240hp for a 2L engine as a bare minimum (since Fiat by default don't tune for power), it sounds like they could get 200hp from the 1.4, so that would be 285hp from a 2L equivalent and more when people decide to build on top of the standard. Amusingly the emissions are still quite good even at those outputs.

Multiair still has a throttle body though (at least for part of its operation); if this were designed such that it didn't need one, more gains might be possible.
 
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