Just constantly variable, I was looking for way to distinguish that from the older systems that only had two position (regular and advanced). Although I've never quite figured out why one would want to be able to vary lift, seems like you could get the same effect by closing the throttle a little. But variable duration would rock.

 

It actually changes the Cam Phasing, by allowing one or both cams to move clockwise or counterclockwise in relation to the crank.
Kinda like when we used to advance our cams, but now on a DOHC motor they can advance/retard the Intake Cam, and Exhaust cam, individually.
Impossible on a pushrod, single cam, motor.
It allows the maximum advance for take off, and retard for top end.

 

Thanks for the info. If GM brings a turbo V6 to the states I'll feel a little better about the bottom end and maybe adding some goodies.

On the gun boards people throw fits when a manufacturer uses sintered small parts acting as though they are certain to break in a few thousand rounds although I've never seen it happen.

Just constantly variable, but couldn't think of the word. I was trying to distinguish constantly variable and its flat torque curve from the older systems that only had two positions and a lumpy torque curve.

 

I guess I can understand the gun guys not wanting sintered parts, but then again no one complains about the Kalashnikov's cheap stamped metal parts.

If it's my carry weapon we're talking about though, I'm all for using the best parts possible.

Gotcha. I've always wondered if anyone used a VVT system that could change the duration and lift, though you're right, I'm not sure why you would want to vary the lift. I thought Ferrari developed a system to do that, but I haven't seen any evidence that it was actually used in a production car.

 

Unless you complicated the cam design and allowed the intake lobes to move a little in relation to the exhaust lobes. Almost like a cam within a cam.

 

I'm pretty sure someone has done that, or something similar. I vaguely remember seeing a camshaft design where the cams were separate from the shaft. I'll try to find it.

 

Camaro has to fight back and fight back hard. I know all that talk about how american Muscle should be v8, but according to the nature of the times, we cannot really be thinking this way. I really do hope Camaro gets a turbo v6 options, just to show the Mustang isnt the only muscle car around.

 

Of course there will be those who will feel no real american muscle car has fewer than 8 cylinders, with enough cubes to displace 4-5 honda i4s. I still encounter some who think the T-type/ GN/ GNX is not a real muscle car. Many even think the Mustang SVO is a joke.

Sure a Turbo 6 will not easily provide 620 hp as in the ZR1, but it will provide the HP of a mid level V8, and the mileage of the V6 that GM so desperately needs. And GM needs this more than us.

Perhaps GM will do the same as what Ford is supposedly doing, offer the 8 and a Turbo six for about the same price. This way, those who need the displacement so bad, will be able to get it.

 

I suspect that this is just to gauge acceptance and one of those engines will go away after a year or two.

It is in the new Viper but I think it is only good for 10-15 degrees. Mopar licensed the use of someone else's design so GM could also use it in the last of the Gen IV small blocks. Hopefully the Gen V small blocks will have DOHC or better yet two cams in the block.

BMW uses a system like that. I think they call it Valvetronic. They claim that the latest version is drivable without a throttle body installed but they have to include one to keep the emissions at down at idle.

Think of it as having a high lift, hi duration cam with computer controlled, adjustable valve lash. So at idle and low load they you keep the lash really loose and the valve doesn't open until the follower is halfway up the lobe, but at WOT it cranks down to zero lash so the valve opens early and wide.

I think FIAT developed a similar system in the 80s, I have no idea what became of it as I don't follow cars I can't buy in the states.

 

That's where I saw it! That was driving my crazy!

I think you're going somewhere with two cams in the block.

The system I was thinking of utilizes tapered cams, with a more aggressive lift/profile at one end of the lobe and a mild one at the other, then the whole camshaft slides across the rocker. The biggest problem I see with the design is that the cams would have to be so wide to provide enough surface area for the rockers or cam follower.

If FIAT had it then chances are Ferrari was using it in some form or fashion.

 

I can't remember where, but I've seen something like that in development.

Don't be so sure. I have personally worked on GN's that DOUBLED their horsepower easily hitting the 500hp range with bolt ons, stock longblock.

As great as the GN's were, the '89 TTA's were sought after more...LC2 powered Trans Am; aerodynamic, handled better, and rarer.

I believe it's time for another GM Trump Card, turbo V6 legend!..

 

The Viper has cam in cam.
Doubling would be scary. If we extrapolate from the 2.0 L LNF’s 260 hp & 260 ft/lbs then a 3.6 turbo would have more power than an LS3. Ford even said last year that they had a prototype 3.5 L twin turbo V6 with 415 & 400 and I've read that they plan to put a turbo V6 (and a new V8)in the Mustang when the Camaro comes out.

But judging by the LNF & 335 boards, they probably won’t leave as much power on the table as it did in the ‘80s. I imagine getting past 500 would require methanol injection (or E85) and maybe bigger turbos. The big question will be what can the injectors flow and can you get bigger ones.

 

If I'm not mistaken Ford is already using a turbocharged (perhaps twin) 4.0L V6 in the some trim level of the Falcon in Australia, putting out around 330hp. Apparently it's capable of well over 500hp with some modification.

 

I think you are thinking of the i6 with yep, 330 hp. That's an engine we don't see here in the US.

 

Ah, yes you are right, it is an I6. Great motors, the packaging is just troublesome. It's usually not worth it. The great thing about cars with an I6 is that you can usually fit an SBC in fairly easily. Take the old Datsuns for example.