Toyota Supra Alleged Revival: 2015.

[Dark]

Originally Posted by madfast

a sporty toyota hybrid is not all that hard and actually nothing to scoff at. look no further than the NSX and 918 for examples of what a hybrid sports car can be. the 918 will turn hybrid from a dirty word, to the future of sports cars. its inevitable.

toyota already has a good engine/motor/tranny in the GS450h. 338 hp/254 ft lbs. not enough? the 3.5L V6 in the 450h uses the Atkinson cycle. they can either supercharge it (Miller cycle), use the Otto cycle 2GR-FSE, or even a supercharged 2GR-FSE to add more power. still not enough? 2UR-GSE anyone?

AWD? yes because you want a small motor/generator on the front axle to capture more regen. the added power, and the stability of AWD, is just a plus. all sport hybrids will most likely be AWD for this reason. the NSX and 918 again are prime examples.

Good explanation/analogy on AWD; howeverm Lexus built RWD hybrid, why not stick with it and keep on improving? I know AWD hybrid is more efficient, but I would sacrifice 5mpg for a balanced RWD hybrid.

[ROJ]

Anybody heard news about Toyota bringing back the Supra?

http://www.motortrend.com/future/fut..._the_pipeline/

[madfast]

Originally Posted by AlmostMDD

So, in reply to madfast, I agree hybrids will be the future, and the hybrid AWD combo just makes sense, but there is not way that I'll be interested in a sports car with a CVT. The only real issue is the transmission. Personally (nothing against those that choose an autobox or Dual Clutch), if it won't have a manual option, I'm not interested.

well toyota uses an "eCVT" and that's inherent in the design of the HSD system. on the other hand, the 918 and NSX will have a conventional transmission in their hybrid system. they chose to go with a DCT but there is no reason they cant use a MT like we see in the CR-Z. having said that, the MT will die sooner than later. advanced hybrids and EVs dont necessarily need shiftable transmissions. and if they do, they'd go with an automated tranny of some sort. the 918 and NSX are the future. that tech will trickle down and soon enough, what we think of as a "sport car" will have some sort of hybrid/EV component. Tesla? Fisker? good ideas, but they are small fish. but porsche? now that's a different story. when the 918 comes out, the automotive world will be turned upside down. there WILL be a paradigm shift in what equates a supercar/sporty car, and "hybrid" will no longer be associated with slow cars, but with advanced performance.

Originally Posted by Dark

Good explanation/analogy on AWD; howeverm Lexus built RWD hybrid, why not stick with it and keep on improving? I know AWD hybrid is more efficient, but I would sacrifice 5mpg for a balanced RWD hybrid.

all said, AWD > RWD. the way the AWD is done in hybrids is a separate motor-generator on the front axle. they weigh very little and are used only when needed. so if programmed so, they dont even have to be used at all on acceleration, thus being 100% RWD, and only used on braking for regen. however, that'd be dumb. why not use what you already have? the front motor will add more power on acceleration, more stability, and a 2 motor system like the NSX you can have tq vectoring.

[Guff]

http://www.ft86club.com/forums/showthread.php?t=5670

[Dark]

Originally Posted by madfast

well toyota uses an "eCVT" and that's inherent in the design of the HSD system. on the other hand, the 918 and NSX will have a conventional transmission in their hybrid system. they chose to go with a DCT but there is no reason they cant use a MT like we see in the CR-Z. having said that, the MT will die sooner than later. advanced hybrids and EVs dont necessarily need shiftable transmissions. and if they do, they'd go with an automated tranny of some sort. the 918 and NSX are the future. that tech will trickle down and soon enough, what we think of as a "sport car" will have some sort of hybrid/EV component. Tesla? Fisker? good ideas, but they are small fish. but porsche? now that's a different story. when the 918 comes out, the automotive world will be turned upside down. there WILL be a paradigm shift in what equates a supercar/sporty car, and "hybrid" will no longer be associated with slow cars, but with advanced performance.




all said, AWD > RWD. the way the AWD is done in hybrids is a separate motor-generator on the front axle. they weigh very little and are used only when needed. so if programmed so, they dont even have to be used at all on acceleration, thus being 100% RWD, and only used on braking for regen. however, that'd be dumb. why not use what you already have? the front motor will add more power on acceleration, more stability, and a 2 motor system like the NSX you can have tq vectoring.

That's why I said AWD hybrid is more efficient. You have an electric motor or 2, power the front wheels while gasoline power the rear wheels. Since electric motor is instant torque, it really helps a lot with acceleration, but... with all that benefits, I still want RWD. Maybe I have to wait for full electric RWD.

[madfast]

Originally Posted by Dark

That's why I said AWD hybrid is more efficient. You have an electric motor or 2, power the front wheels while gasoline power the rear wheels. Since electric motor is instant torque, it really helps a lot with acceleration, but... with all that benefits, I still want RWD. Maybe I have to wait for full electric RWD.

why? there is almost no benefit considering the front motor need not be used at all if they wanted. the AWD in these systems can be thought of as RWD with AWD assist, a sort of AWD KERS if you will.

[Dark]

Originally Posted by madfast

why? there is almost no benefit considering the front motor need not be used at all if they wanted. the AWD in these systems can be thought of as RWD with AWD assist.

Yeah, I just want to see what they can do. Leave something easy to lazy people, Toyota engineer should do the hard task.

[suzuka]

Originally Posted by AlmostMDD

So, in reply to madfast, I agree hybrids will be the future, and the hybrid AWD combo just makes sense, but there is not way that I'll be interested in a sports car with a CVT. The only real issue is the transmission. Personally (nothing against those that choose an autobox or Dual Clutch), if it won't have a manual option, I'm not interested.

A CVT can have virtual manual shifts and is found to be as responsive and efficient as DSG/manual transmissions while being smoother in operation than DSGs. This was recently demonstrated by Honda when they unveiled their future power/drive-trains for 2014 model year.

Looks like Toyota will choose performance-oriented CVT because it could be far cheaper and ligher than DSGs while possessing the virtues of DSGs.

[serialk11r]

The issue with electric only powered front wheels is at higher speed they produce less and less power, unless you put a multiple speed gearbox in. You could solve this with a more powerful motor, but since the energy is all eventually coming from the gas engine you need a bigger gas engine too, like the 918. Normal people cars are not going to come with 700hp, ever.

It's the best setup as far as regeneration goes though, since the front end handles most of the braking. Significant regeneration capability would mean big motors, which costs a lot anyways, so I'd rather see someone build a more reasonably priced, mild hybrid sports car, especially since sports cars command an automatic premium. There is one thing, if your electric motor is powerful enough you could just hook the engine to the transmission without slipping a clutch to start, but you also need the capability to idle and generate power for lights and whatever at a stop, so perhaps what they could try to figure out is to use the electric motor to stabilize a lower speed idle.

suzuka, virtual manual shifts on a CVT are completely retarded, sorry :P

[old greg]

Originally Posted by serialk11r

so perhaps what they could try to figure out is to use the electric motor to stabilize a lower speed idle.

Toyota already did that

Originally Posted by serialk11r

suzuka, virtual manual shifts on a CVT are completely retarded, sorry :P

Almost completely retarded.
CVT's can be very effective in high performance driving, but they suck all of the joy out of the engine noise. It's just a constant droning at full throttle. A manually shifted CVT may be slower and less efficient, but at least it lets the car make pretty noises.

[serialk11r]

Ah, you can tell I haven't been following closely enough :P I just remember seeing that in some paper or something somewhere, wasn't sure if anyone had actually got it working.

Pretty noises are cool I guess

[TuxedoCartman]

There's one concern I have with making hybrid sports cars, and maybe it's been addressed and I just haven't read it (I'll admit to being fairly uneducated on the topic.)

Lithium batteries are prone to catching fire or exploding if they're damaged. While it's of a minimal concern on a Prius (where every driver is slow-poking along while watching their real-time fuel computer), isn't that a bit of a safety concern for high-power sports cars? I mean, will we ever see a hybrid car racing in the JGTC?

[serialk11r]

I'm pretty sure Lithium Iron Phosphate batteries are quite safe as far as thermal runaway goes. I'd be more concerned about a large tank of volatile hydrocarbon fuel (which has like 50 or something times the energy density of batteries) sitting near a very hot engine.

Don't discount the safety requirements of a Prius, it's a road car that will ultimately be crashed much more than a handful of race cars poking around simply because there's millions of them on the road, and plenty of Prius drivers go 80mph :P

Besides in a racing application, there's likely to be heavy ultracapacitor use, and their energy density is even lower so I think it should be okay.

[old greg]

Originally Posted by TuxedoCartman

There's one concern I have with making hybrid sports cars, and maybe it's been addressed and I just haven't read it (I'll admit to being fairly uneducated on the topic.)

Lithium batteries are prone to catching fire or exploding if they're damaged. While it's of a minimal concern on a Prius (where every driver is slow-poking along while watching their real-time fuel computer), isn't that a bit of a safety concern for high-power sports cars? I mean, will we ever see a hybrid car racing in the JGTC?

Gasoline is even more prone to catching fire. The issue with the Volt fires was primarily that the wreckers weren't discharging the battery packs following the accidents. In fact, the still-charged battery packs did not catch fire for days to weeks after major side impact damage. The "fix" that GM performed was to reinforce the side of the battery compartment to improve the battery pack's impact protection. It was completely unnecessary from an engineering standpoint, but the Volt needed some good PR. To judge the safety of Lithium batteries based on the sensationalist news coverage of burning Volts makes even less sense than judging the safety of gasoline powered cars on the Ford Pinto.

Lithium batteries are used in F1 and now in the FIA WEC (Le Mans, et al) as well. If/when JGTC rules allow hybrid drivetrains to be used in way that would improve a car's overall competitiveness, then yes, we will see them there as well.