[vitoal18t]

What would it take to make "VTEC" for Duratec?

I think Honda released the patent long time ago.

Money is probably #1 issue, it costs too damn much to engineer and cast completely new custom head and there aren't that many people waiting to dump atleast $5000 on a new head.

But then 230fwhp would be possible in a street car.
Probably will never happen.

 

[Egz]

It all depends on your definition of 'street'. Honestly, I think its quite do-able. Just takes some money, and some tuning.

 

[Tailhooker]

ok, I'm going to sound stupid on this one... but so be it. Is there any way to get a mazda3 head and work with that? I know it's variable cam timing or something... but either way, can we do it?

 

[vitoal18t]

But Mazda3 isn't Variable Valve Timing, it is Variable Cam timing. Cam shaft just gets adjusted by a few degrees.

What I had in mind was 2 cam profiles, like you find in Celica GTS, Acura RSX, and Lotus (Celica GTS engine

) an many other cars.

Pretty much it is a very agressive cam for high rpm and mild one for low RPM cruising. If you look at their dynos there is a huge torque spike at around 5000rpm when performance profile engages.

 

[YellaPZEV]

personally, for the price, I'd pay to have a turbo setup made for the car. by the time you engineer the setup, you'd be way too many thousand into it for the small power you'd gain. plus you'd have to work out a computer tune for it.

you'll get an even bigger spike at like 3000-3500 if you rigged it with a T3/4.

 

[2020]

In the case of Honda, for the 2nd cam profile, it is actually a third cam lobe between the two others. A special lifter is disengaged until the specified RPM, then the higher lift center lobe operates both surrounding valves. This lifter is an integral part of the head design, so I doubt you could add it without casting your own head.

If it makes you feel better, a lot of serious race engines defeat the Vtec feature and just run a single high lift profile.

 

[MarcyMotorsport]

Or you could put a K24 hybrid wit a Type-S head in your Focus...

 

[blueovalbaboon]

the idea here is to build a motor that rivals the K24, which i think this one can

 

[desratt]

ford is putting the variable cam timing on the 2.3 ford fusion to be released around september.

 

[SOON2BN-FOCUS]

But Mazda3 isn't Variable Valve Timing, it is Variable Cam timing. Cam shaft just gets adjusted by a few degrees.

What I had in mind was 2 cam profiles, like you find in Celica GTS, Acura RSX, and Lotus (Celica GTS engine

) an many other cars.

Pretty much it is a very agressive cam for high rpm and mild one for low RPM cruising. If you look at their dynos there is a huge torque spike at around 5000rpm when performance profile engages.

The Mazda 3 is VVT (variable valve timing)!

 

[Pzev]

Actaully its not

 

[SOON2BN-FOCUS]

Actaully its not

Actually it is according to the shop manual I have on CD and my Mazda3 Service Highlights book.

 

[Pzev]

Then its creative marketing. Everything I have ever heard about the car has said that is actually variable cam timing. Whether or not they can legally say its vvt I don't know.

 

[MarcyMotorsport]

Variable Cam Timing (VCT) and Variable Valve Timing (VVT) from Ford/Mazda are the same. VCT/VVT can only advance or retard the cam(s) in relation to the crankshaft, using a hydraulic/electronic cam gear configuration. The cam timing is technically "Variable", but the cam itself does not change it's permanent timing events. We can only dream about changing duration on the fly...

 

[Oreo]

Ya know... I know this is a bit of a dream... and hopefully not TOO off topic... but it'd be REALLY REALLY cool if you could use honda's version of 2 or 3 cam lobes per valve using the "runners??" to switch between the stages. THen hook the whole setup to a couple switches in the cabin. 1 set for daily driving, and the other two for low RPM / high rpm performance. I mean... I guess there could be all sorts of combinations you could use. The possibilities would be endless if you incorporated SCT tunning into the equation.

I guess by the time all THAT was developed though... you could just buy a lotus or something even nicer.

 

[aerostudent]

You would have to build and engineer a new head from the ground up. Just to throw a # out there I would guess in excess of $10k. If you are going to dream about stuff like this then dream big, formula 1 cars use pneumatics...

 

[vitoal18t]

What do you mean by pneumatics? Each valve has a pneumatic actuator that controls it seperatly from the rest?

I know that concept existed, like using solenoids to control each valve, but I didn't know F1 uses it. I guess I don't get out much, thanx for the info!

I don't think in a case of designing a new head engineering is a problem. There are plenty of geeks around who like to crunch numbers in the name of speed.

Money would be the major issue to make and test the thing. I was just curious if anyone is aware of some "short cuts". K24 head sounds pretty cool, but all the people who like bragging about their car and Ford will be freaked out.

Honda Guys says - "Hey that is a damn quick Focus, What do you got there?"

Focus guy - "Some fine tuned motor....oh and a honda head VTEC!!!!

"

 

[Enigma]

My senior design project at school originally was electronically-controlled valves for the Formula SAE race car. My lab partner didn't pull through though.

Imagine any cam profile, any duration, any time, on the fly.

-Jesse

 

[vitoal18t]

Nice...what is keeping this technology from going mainstream? I mean what is the main challenge? Solenoids are fast enough from what I know and the rest is just High speed microcontroller.

I guess it is difficult to control valves with in the cylinder. I mean ON/OFF motion and duration should be a piece of cake, but variable lift might be pretty tricky. I am sure you have some insights since you did your senior project in it

.

I am still curious why companies like BMW, Honda not using it?

 

[aerostudent]

cost and tuning. Durability may also be a big issue.

The only way I can think of to do the initial tuning would be to toss it on an engine dyno and go with regular intervals of say 50rpm and go through the load scale and try each permutation. It would be a nightmare. F1 motors are million dollar motors for a reason.