Hybrid question

do you think car manufacturers will make a hybrid with a turbo or supercharged engine? or maybe use a M/T?

Reply to
EdV
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No, because a naturally aspirated engine is more efficient.

And a CVT is more efficient that a manual transmission.

That idea of using hybrid technology is to improve efficiency.

If you want a car with a manual transmission or a turbo, you have plenty of choices.

Jeff

Reply to
Jeff

I should add that the Honda Civic hybrid used to have a manual transmission, but I believe they are all the more efficient CVTs. And Toyota's Synergy drive includes a CVT. No need for a manual.

Jeff

Reply to
Jeff

It would be a logical way to boost the power on the existing powertrain for a slightly heavier car, or to increase the GVWR capacity.

A turbocharger uses waste energy going out the tailpipe to increase the horsepower output of the engine, at the cost of having to manage detonation and some added combustion chamber heat and pressure. As long as the radiator and the engine are up to the added stress they work great.

Might want to include an aftercooler to relieve the thermal stress.

Doubtful - the whole thing needs to be under the computer's control for max efficiency under normal conditions. You could see a "Sport Mode" button where you tell the computer you're going to be flogging it and don't care as much about economy at the moment.

The only thing I care about on /any/ car is if I see an imminent collision and need to do the "Boot Scoot & Boogie" and I stomp the gas pedal through the floorboards, the powertrain responds with everything it's got, right now. Screw traction control, just GO. Boil 'em, they'll hook up when they get hot.

Automatics are actually much better at that, it takes you precious time to stuff the clutch in and grab second or third gear.

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Reply to
Bruce L. Bergman

"EdV" ...

I pretty much agree with Bruce here in that the turbocharger might help in applications where more power is needed, but that might be addressed by better electric motors. Maybe a bit of both down the road. It will be interesting to see what comes of this.

I see less of an application for manual transmission (if this is what M/T is), as with all this power swapping going on, the mechanism that transmits power from the engine(s) to the wheels will need to be pretty sophisticated, and I believe that the manual transmission might just get in the way of this. Tomes

Reply to
Tomes

The Insight has a M/T.

Reply to
Hachiroku

The reason I asked is because M/T, manual transmission, shows better mpg on non-hybrid vehicles, even with the CVT. e.g. Nissans 08 Coupe gets 32hwy manual and 31hwy cvt. And about, turbo charging, intercooler, and supercharging, I was thinking if they can further reduce engine displacement. I dont know though if what cost more...superchargers or bigger electric motors

Reply to
EdV

I am not sure why the CVTs have lower mileage than the manuals.

I have a feeling that it has to do with the way the CVTs are controlled by the computers. A manual transmission has 5 or 6 gear ratios. A CVT has infinite gear ratios.

The superchargers use power from the engine to pump air into the engine. They reduce efficiency.

Turbos are more efficient than superchargers, but I don't know if they increase efficiency. I suspect it is better to use the electric motors, because you need more cooling capacity for the engine because it will make more heat with the turbo, more control circuitry, etc.

But it doesn't really matter too much about space. Efficiency is what counts.

jeff

Reply to
Jeff

If you're talking about a manual, shift it yourself transmission vs. a standard automatic transmission, that's no longer the case. Honda with the new Civic broke that barrier; the auto trans car gets better mileage than the manual trans car.

Reply to
Elmo P. Shagnasty

The reason that most CVTs get less mileage is that they require a high pressure hydraulic pump to be able to squeeze the "cones" together to keep the belt tight and hydraulic pumps require energy. The Toyota Hybrid Synergy Drive (in the Prius) only has a low pressure pump for bearing lubrication and all the parts are permanently engaged. The only thing that ever shifts is the parking pawl. Manual transmissions don't have any pumps therefore they are usually efficient. The problem with a manual is that the mileage depends on when and how you shift. If you always wait for the redline before shifting you won't get very good mileage.

A turbocharger could help mileage but it also has downsides such as needing increased oil changes and you have to let it cool and spin down before shutting off the oil supply otherwise it will coke the oil and destroy the bearings. A solution would be to use an electric oil pump but that adds complexity and is just another part to fail.

Reply to
Daniel Who Wants to Know

That's true. But I doubt that the amount of energy used by the hydraulic pumps is that great. And toroidal CVTs don't use cones.

True. But the how good the mileage is in a car with an automatic, hybrid or CVT also depends on how the driver accelerates.

But you will get to rebuild the engine sooner and get more wear and tear on the transmission and other powertrain components than you like.

A turbocharger doesn't save fuel. It increases the work that the engine must do to push out the exhaust in the power stroke. However, turbos also decrease the power-to-weight ratio and size of the engine, which can result in overall fuel savings.

Jeff

Reply to
Jeff

What if they hook up the turbo to the electric generator so the rotation is converted to electricity

Reply to
EdV

It will still take put more work on the engine, which will have to work harder during the exhaust stroke. However, you might end up with more power generated than extra power that the engine has to do (if there is less energy in the exhaust gases).

Jeff

Reply to
Jeff

Honda used to offer the Insight and the Civic Hybrid with a manual transmission. The Insight is no longer produced, and the HCH now is only available new with the CVT.

AutoSpeed magazine has put a turbocharger on a NHW10 original Japanese Prius, if you want to read up on it. The editor/owner of that vehicle (in New Zealand, IIRC) does post on the Prius_Technical_Stuff yahoogroup if you're interested in reading about it and cannot find a back issue.

Usually I hear of the electric motors in the hybrid as being compared to a turbo on a regular car (in that it provides extra power/ acceleration/torque/etc. as needed), in that you get more performance out of a smaller engine. Look into the performance-based hybrids, like the Honda Accord hybrid or the Lexus hybrids, for examples.

Reply to
mrv

Umm... Wrong. Turbos increase efficiency by using exhaust-gas energy that otherwise would be wasted to force more air into the engine.

Reply to
dizzy

An obsolete notion, since modern turbos are water-cooled. In normal conditions, there's no need for an unusual "cool down" period.

Reply to
dizzy

No, the oil is to lubricate the turbos as they spin down.

Jeff

Reply to
Jeff

Wrong again.

At best, they can increase power by increasing the amount of fuel that can be burned at one time during one cycle of the engine. But that doesn't increase efficiency.

And the energy in the exhaust is used to get the exhaust out the exhaust pipe.

Jeff

Reply to
Jeff

turbos are used in diesel engines to increase fuel efficiency and I think it may also be applicable to petrol and hybrids. I'm not sure if it will violate law of diminishing return on hybrids which is already fuel efficient.

Reply to
EdV

A turbo can increase the power-to-weight ratio of an engine. If you increase the power to weight ratio of an engine, you can use a lighter engine, resulting in better fuel economy for the car. So it is like have a V-8 in a 4-cyl package.

But it also lets the engine run in a more fuel-efficient manner, more conditions more optimum for better fuel efficiency.

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So, gee, I was wrong.

It happens.

jeff

Reply to
Jeff

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