Hybrid car engines are very expensive and efficient than the normal diesel car engines. People do prefer more the hybrid cars now a day than that of diesel cars. Hybrid cars have more powerful engine and can run for a long time without any engine defect. These hybrid cars are really very efficient and i have gone through the above article to know about it.
The alternator-starter is half of the stop-start system, the other needed part is the means to disengage the engine so that the vehicle can coast. The simplest system would not need any of those fancy computers because it would rely on driver judgement, which is good for cutting fuel consumption in half for city driving. The problem with that system was the wear on the shift and clutch linkages from much greater use. Once some simple clutching system is developed, the rest will be easy.
NO, it will not be for everybody, because many folks lack the skill needed to drive that way, and they are unable to concentrate enough to handle that kind of driving. But if they could do it in Mexico in the early seventies, with no outside funding, doing it today should not be that much of a challenge.
I can see many advantages to the mild hybrid approach but there are of course shortcomings.
One is the inability to drive the vehicle without the engine engaged and running.
Another is the efficiency of braking energy recovery, especially if there is a torque converter type of automatic transmission. Braking recovery needs to optimized for low engine RPM so braking energy is not dissipated as heat pushing engine compression.
The use of a dual clutch automatic could alleviate much of the braking loss if the alternator could be made to deliver substantial charge rate at engine RPMs under 1000.
When I was buying my F150, I looked at the eco-boost. The V6 was 1 mpg more than the V8. The eco-boost V6 was one more mpg than the V6. The eco-boost was about $3k more than the V8. I decided to have a V8.
Ford's ECO Boost technology is giving them V6 performance in the four cylinder format and the V6 is competing with with the V8's. It really is something that changes the overall equation. WHy take the hit for a heavy V6 when you can use a very powerful 4 and get terrific mileage to go along with it. I must admit I'd love to see an EcoBoost V8 with about 600+ HP!
I think what we are seeing is that the V-6 is the higher grade option, in the mid sized cars with upgraded package. Once the province of V-8s. Fours are becoming prevalent even in mid-sized cars with the basic feature package.
For example, the short wheel base Epsilon platform cars (platform designed by Opel), like the new Chevy Malibu and new Buick Regal, are turbo fours only (so far anyway). But the Buick Lacrosse, which is the long wheelbase Epsilon, comes with the V-6.
If you look at Mercedes Benz, the C class and the SLK come either with turbo fours or with the new 60 degree V-6. And the luxury models, all but one, now come with only turbo V-8s. For some odd reason, Mercdes Benz doesn't yet offer turbo V-6s, although I'm willing to bet that's just around the corner.
It looks like, for a given power output, you can get better EPA fuel economy ratings with turbo engines than naturally aspirated engines. Probably because, when driven mildly, e.g. city driving without hard acceleration, the turbo engine operates like low powered small displacement engine.
Above, I said I do not know all the reasons, but the six seems to be going away, at least in the power range I've been talking about. I think there are a number of reasons. These might include economics, fuel efficiency, physical size and reliability.
I like the six too, my favorite was the VR6 because of its compactness without too many compromises over the straight variety (actually with much of the soul and attributes of the straight) but it too seems to headed towards extinction.
The vibrations of the four seem to have been sufficiently tamed, internally and externally.
The bottom line these days seems to exclude elegance just for the sake of elegance. Power, efficiency, compactness, reliability and cost are what rules.
Intake pressure boost, sophisticated valving and fuel deliver,and electronic control of everything have changed the game. We have new goals and rules. Metallurgy and mechanical engineering are also much advanced.
And this is all part of a bigger platform and the ecosystem it lives in.
A V-6, or even better a straight six, is a sweet, sweet engine. No matter how much you try to balance a four with extra balance shafts, it's always going to be a buzzy four.
This has nothing to do with power. It has to do with naturally balancing the first and second moments. I'd much rather have a 2 liter 6 cylinder than a 2 liter 4 cylinder, EVEN IF the 6 did not produce more power.
Blog Doing Math in FPGAs Tom Burke 23 comments For a recent project, I explored doing "real" (that is, non-integer) math on a Spartan 3 FPGA. FPGAs, by their nature, do integer math. That is, there's no floating-point ...