spwolf

If you guys are talking about CO2 emissions, they are directly related to fuel consumption. Less fuel, less CO2.

spwolf

yes, that will likely end up being hybrid based on 3.5tt engine...

gengar

The battery in a hybrid is dead weight too. In any case, the purpose of cylinder deactivation opposes that of hybrids. Hybrids have huge advantage in stop-and-go city traffic. Cylinder deactivation is good for long highway cruises at constant speed.

To be clear, I wouldn't choose to have cylinder deactivation in any vehicle I own. It's just the question of the effectiveness versus turbocharging and why manufacturers choose one instead of the over.

gengar

The discrepancy, of course, comes in how the testing is done. Another reason why environmental regulations are all largely BS and have had little impact on actually improving the environment.

As a side note, EU regs do include emissions other than CO2, which turbochargers apparently also have advantages at.

Toys4RJill

How come you are so opposed to turbos and the environmental regulations?

I think it has to do with marketing. A big 6.2, 400+ V8 in a Cadillac Escalade is more in line with what buyers expect versus a 400+hp, 3.5tt V6 in a Navigator. I know the Ford/Lincoln has done well, but so has Cadillac with their method.

Stroock639

have you heard the LFA?

gengar

I'm fine with environmental regulations that do what they claim they are supposed to do. I'm not fine with bureaucracy and BS that causes automotive manufacturers to spend billions of dollars trying to exploit loopholes and taking advantage of testing parameters to design vehicles that don't actually benefit the environment. VW's emissions scandal, for example, was completely predicated on these flawed tests.

Remember that when these companies spend billions of dollars on this stuff, that's the consumer's - meaning your - money. So if there is no measurable improvement as a result of this expenditure, or if the money could have been better spent elsewhere to implement meaningful change, then this is just bureaucracy and big government screwing over the little guy.

Toys4RJill

So how would the turbo be BS in contrast to a larger engine? I would interested in your opinion, I always thought Toyota would go turbo on the Toyota brand lineup and I was quite surprised they went with their non-turbo dynamic force engines. (Compared or how Honda went turbo). Look forward to your response. Hopefully, only you will respond.

gengar

Again, nothing wrong with turbo, just like there's nothing wrong with environmental regulations. There's everything wrong with turbo (and environmental regulations) if it's just to beat bureaucratic governmental regulations that don't do anything.

coolsaber

Depends on how frequent that hybrid battery stays dormant. As you said the Cylinder tool requires very finite conditions to operate. Whereas a hybrid system can vary usage more frequently. Together, such as in the new yaris motor, the efficiency metric would increase. Cylinder deactivation by itself to me is pointless overcomplication due to the limited yield of return.

riredale

I don't know, I'd love to see data on the fuel flow of a big V8 at idle running 8, 6, 4, or even 2 cylinders. It seems to me that a big V8 running on 4 or 2 cylinders would have excellent fuel flow numbers, since the dormant cylinders wouldn't have pumping losses if the valves were shut and the only friction would be from the piston rings, but I don't know how much that is. Certainly Toyota could build an engine and computer that would make transitions virtually seamless. They certainly have a brilliant design in the hybrid drive of my RX. Buttery-smooth operation and the fuel economy of a diesel.

Stroock639

i feel like to fully be able to take advantage of cylinder deactivation you would need to be able to independently control the valves, so that the deactivated cylinders wouldn't be wasting energy opening and closing them

we need that koenigsegg free valve technology to be made public lol

4TehNguyen

iTrader: (1)

plenty of examples out there of cars with similar mpg making significantly different emissions, you cant make a direct correlation with mpg. Its even in the example you quoted the RCF and M4 make similar mpg yet different emissions

coolsaber

Honest question to the engineers on here, can anyone clarify how emissions on turbos operate throughout the rev range under load vs a NA motor?

my layman opinion here would be turbos kick NA vehicles under light load, but under full throttle romps the Turbo is worse then a NA motor?

4TehNguyen

iTrader: (1)

been a while since i saw this one but maybe it will help