If you could change one thing about...

**IPD** · 10-18-2010, 09:32 AM

Originally Posted by DocWalt

Why would you want to slide the camshaft? I don't get it, lol.

http://auto.howstuffworks.com/camshaft2.htm

it's the best system available until we go to solenoid activation. saves weight over adding an additional camshaft.

**terrets** · 10-18-2010, 09:39 AM

Cool.

**DocWalt** · 10-18-2010, 10:54 AM

MIVEC adjusts the cam timing, which just about negates the need for sliding a cam. Yes, MIVEC combined with a sliding cam would be fantastic, but incredibly expensive for a street car. Hell, a sliding cam alone is going to be incredibly expensive.

**IPD** · 10-18-2010, 10:57 AM

Originally Posted by DocWalt

MIVEC adjusts the cam timing, which just about negates the need for sliding a cam. Yes, MIVEC combined with a sliding cam would be fantastic, but incredibly expensive for a street car. Hell, a sliding cam alone is going to be incredibly expensive.

i never said it would be cheap. that said, it is the best vvt solution on the market, imho. better technologies have yet to be fielded. there's no need to combine mivec, vvti, vtek, etc with the ferrari solution. ferrari simply found a way to vary valve timing without the need for an additional cam.

**Atrosity** · 10-18-2010, 05:14 PM

Add a god damn targa top to our platform!

**DocWalt** · 10-18-2010, 05:38 PM

Originally Posted by inperfectdarkness

i never said it would be cheap. that said, it is the best vvt solution on the market, imho. better technologies have yet to be fielded. there's no need to combine mivec, vvti, vtek, etc with the ferrari solution. ferrari simply found a way to vary valve timing without the need for an additional cam.

You can use slightly different cam profiles or timing, but you can't use any in between positions, which is where the Ferrari cam fails.

**IPD** · 10-18-2010, 07:14 PM

not sure what you're referring to by that. that pic isn't a good one. my understanding is that a ferrari cam has a continuous face for each valve. meaning that the cam lobe looks somewhat like an amorphous blob. the cam does not only have 2 positions to operate in, but is slid incrementally based on computer input. i could be wrong however....

in any case, i'm really surprised we don't have solenoid activated valves in widespread commercial production. that, or rotory combustion chamber valving.

**DocWalt** · 10-18-2010, 08:49 PM

I guess I'm just expecting the tolerances to get off a bit and different valves to act different because they just "ride" differently in their guides. FWIW, MIVEC style valve timing combined with the different lobe profiles offered by the Ferrari tech would be ideal, but very expensive, and hard to manufacture for anything beyond limited numbers with our current production technology.