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2020 WRX Prototype (new pics)


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If CVT was that great it would have gone mainstream years ago.

 

It did though. The Prius and Outback are pretty mainstream.

 

I still wouldn't want one, I prefer stick, but I can see how for people who view cars as uninteresting appliances it doesn't matter. My girlfriend loves her old Nissan with a CVT.

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Small engines like mopeds have had CVTs for many years. The trouble has been to make them work with more engine power and Subaru tried the style of CVT that Nissan has back in the 80's already and from a fuel economy perspective it was fine, but not from a reliability perspective.

 

 

First vehicle that I did drive with a CVT was a Claas Combiner - farm equipment using a fat rubber belt.

 

 

If there were general problems with the chain solution we would probably have seen it by now.

 

But everything eventually wears out.

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Small engines like mopeds have had CVTs for many years. The trouble has been to make them work with more engine power and Subaru tried the style of CVT that Nissan has back in the 80's already and from a fuel economy perspective it was fine, but not from a reliability perspective.

 

 

First vehicle that I did drive with a CVT was a Claas Combiner - farm equipment using a fat rubber belt.

 

 

If there were general problems with the chain solution we would probably have seen it by now.

 

But everything eventually wears out.

 

You basically nailed it, small engines no problem and light vehicals like mopeds sure, I mean many bikes can use a tooth belt for a final drive but you notice that high Hp you move to chain. Great fat rubber belt and farm machinery sure. Its got it's place, just not in my car.

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Subaru's CVT is a travesty.

 

CVTs can be great if it wasn't for a lot of dumb consumers and dumb engineering.

Dumb consumers think the car feels weird if they can't feel it "shifting," so dumb engineers make the CVT respond in a way that makes it feel like it's shifting.

 

On paper, a transmission that can hold your engine in its peak power range or peak economy range the whole time you're driving sounds amazing and too good to be true. In the real world, they're made weak and conform to consumers.

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Subaru's CVT is a travesty.

 

CVTs can be great if it wasn't for a lot of dumb consumers and dumb engineering.

Dumb consumers think the car feels weird if they can't feel it "shifting," so dumb engineers make the CVT respond in a way that makes it feel like it's shifting.

 

On paper, a transmission that can hold your engine in its peak power range or peak economy range the whole time you're driving sounds amazing and too good to be true. In the real world, they're made weak and conform to consumers.

 

100% agree. The fake shifting crap just adds stress to the system. If you’vre Going to use a CVT instead of a slushbox or DSG take advantage of it’s strengths!

 

Also I wouldn’t call them weak. They don’t fail in stock configuration often, and the same JATCO core bits are used in other cars that at both heavier and have more power. You see them blowing up a lot of modded FXT’s because Cobb/EcuTEK never took the time to dig into the controller code. A CVT requires tighter communications between the motor and transmission so it can set the pully tension. You bump torque up to the moon with e85 and don’t update those parameter and it’s not claiming nearly tight enough to prevent slip.

 

Some people in the Russian Subaru community have figured out how to fix some of this, but you have to use their obscure tuneing platforms with little to no English documentation.

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On paper, I am a dumb driver.

 

I haven't owned a CVT, but I have driven a quite few them as rentals and couple friends cars. The simulate shifts feel better from a driver's stand point. The cars I have driven sound like shit holding WOT at redline as well, even the Nissan Maxima v6 doesn't sound that great at 6K rpm. I would sacrifice a couple 0.1-0.2 of acceleration or couple 0.1 or 0.2 of mpg for a better feeling driver than a disconnected appliance.

 

For the same reason, I will pick a MT that is a couple 0.1 of second slower than a faster DSG/Automatic for the driving dynamics alone. When I am driving 99.9% of the time I am not trying to extract 100% of acceleration of a vehicle.

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I haven't owned a CVT, but I have driven a quite few them as rentals and couple friends cars. The simulate shifts feel better from a driver's stand point. The cars I have driven sound like shit holding WOT at redline as well, even the Nissan Maxima v6 doesn't sound that great at 6K rpm. I would sacrifice a couple 0.1-0.2 of acceleration or couple 0.1 or 0.2 of mpg for a better feeling driver than a disconnected appliance.

 

 

The shift feel thing is just making it “how it used to be”. It’s fakeing the feeling just to make it how you’re used to. If you start with someone with no pervious experience with cars the would more often than not choose the fixed RPM feel. MT cars don’t sell well in the USA outside of some niche markets. In China, where most people haven’t owned cars until recently, MT’s aren’t sold at all.

 

Have you ever driven an electric car? I’ve never heard someone say they wish they shifted like a gas powered on. And throughfully the torque is so instantaneous when you floor that the jerk feels almost like traditional AT downshifting.

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I love the rubes saying that it's a bad idea that should only be applied to light and low horsepower vehicles.

 

I remember other morons saying the same ignorant shit 15 years ago that it would only ever work in snowmobiles and it would never make it in mainstream vehicles. Then it worked its way up into the Nissan line, then Subaru was using it in most of Outbacks.

 

Now you have it in a 4600 lb vehicle with a 5,000 lb tow rating.

 

Sure, guys. Just let the engineers know they should shut it down because they couldn't possibly improve on a system that was largely ignored and undeveloped until recently. Clearly, they haven't made any progress in the last 15 years worth further development.

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100% agree. The fake shifting crap just adds stress to the system. If you’vre Going to use a CVT instead of a slushbox or DSG take advantage of it’s strengths!

 

Also I wouldn’t call them weak. They don’t fail in stock configuration often, and the same JATCO core bits are used in other cars that at both heavier and have more power. You see them blowing up a lot of modded FXT’s because Cobb/EcuTEK never took the time to dig into the controller code. A CVT requires tighter communications between the motor and transmission so it can set the pully tension. You bump torque up to the moon with e85 and don’t update those parameter and it’s not claiming nearly tight enough to prevent slip.

 

Some people in the Russian Subaru community have figured out how to fix some of this, but you have to use their obscure tuneing platforms with little to no English documentation.

 

Whats interesting here is, most of the Subaru CVT failures are for the 2010-2012 models, which did NOT have shift points. In 2015 Outbacks got shift points, and to be honest I haven't heard of as many failures on those (yet?)

 

I would agree on modded turbo Subarus, but there are failures on bone stock NA motors too. I think it's just growing pains of fairly under developed tech.

 

I love the rubes saying that it's a bad idea that should only be applied to light and low horsepower vehicles.

 

I remember other morons saying the same ignorant shit 15 years ago that it would only ever work in snowmobiles and it would never make it in mainstream vehicles. Then it worked its way up into the Nissan line, then Subaru was using it in most of Outbacks.

 

Now you have it in a 4600 lb vehicle with a 5,000 lb tow rating.

 

Sure, guys. Just let the engineers know they should shut it down because they couldn't possibly improve on a system that was largely ignored and undeveloped until recently. Clearly, they haven't made any progress in the last 15 years worth further development.

 

Agreed, with enough time and R&D I think CVT will be just as reliable as planetary AT. I've heard of plenty of traditional AT's starting to slip (especially after oil changes) and needing to be fixed, but most of the time it was cheaper to just install a new transmission.

 

That was the point I was making way earlier in the thread, buying a brand new AT, MT, or CVT will cost about the same, there are just not a lot of used CVT's to choose from so they are still pretty pricey used too.

 

With that said, that doesn't excuse Nissan's track record. I'm hoping Subaru's high torque CVT is also more reliable then the one in Outbacks, this is why I wont buy an Ascent for a couple years.

05 LGT 16G 14psi 290whp/30mpg

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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The CVT is just a stop gap, it will probably be gone in 15 years.

 

For one the majority of cars on the road will be electric by 2035. I could see the CVT coming into its own, but only if the vehicle weight and therefore required power falls significantly. For vehicles with one driver, a 500cc engine and mass sub 400Kg combined with the refined engineering for the CVT over the next 15 years. Cars will be forced to go smaller than they are currently, not only for emissions but due to congestion caused by continual population growth and increased fuel cost.

 

The car as we know it currently is certainly in its golden years. Enjoy that POWER when you put your foot down while you can.

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I'm in no way defending CVT reliability, but this just shows that even traditional Auto's, with lots of gears, are having issues nowdays: https://www.thetruthaboutcars.com/2017/11/nine-speeds-another-problem-hondas-gear-iest-transmission/

05 LGT 16G 14psi 290whp/30mpg

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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In 15 years then it's probably electric cars that are most common, but I suspect that the CVT is here to stay for the cases where you have a combustion engine, and then it's most likely in a hybrid solution.

 

Oh in 15 years we will be teleporting everywhere and none of us will even remember what a CVT or electric car was!!!!! :spin:

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Covert the issues with the CVT from 2010 was a bad torque converter design that wore out. The CVT is super robust and has more room for safety than anything else since then (measured by Nm)

 

 

What they really need to do is stick with the real CVT and eliminate fake oft points and make it more user friendly to check fluid level and change fluids out at some regular interval.

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Covert the issues with the CVT from 2010 was a bad torque converter design that wore out. The CVT is super robust and has more room for safety than anything else since then (measured by Nm)

 

 

How do you mean that? Do you mean the WRX CVT is good for 400+ hp? I'd buy one tomorrow..

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How do you mean that? Do you mean the WRX CVT is good for 400+ hp? I'd buy one tomorrow..

 

Core bits are good for ~580nm input torque. So "Yes", but only if your boost only happens when the TC is locked.

 

Same issue we had with the 5EAT: it's not a mechanical issue. TCU code needs to be reverse engineered to really make it survive.

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Pilot1226 agreed, I think CVT fluid should be much easier to change at home, but seeing how it needs a cleanroom for assembly, maybe they don't want average joe changing it.

 

The sad thing is, all the fuel economy money savings are lost after the first dealer CVT oil flush :lol:

 

Do you have any links to the NM ratings? Everything I saw, CVT's were typically only marginally rated above the stock engine output.

 

How do you mean that? Do you mean the WRX CVT is good for 400+ hp? I'd buy one tomorrow..

 

Our 5MT's are having trouble with 300hp, so it would be unreasonable to expect CVT to do that :lol:

 

Core bits are good for ~580nm input torque. So "Yes", but only if your boost only happens when the TC is locked.

 

Same issue we had with the 5EAT: it's not a mechanical issue. TCU code needs to be reverse engineered to really make it survive.

 

Which CVT is rated for ~430 Crank TQ? The high torque ones used in the WRX, 3.6L, and Ascent?

 

Since CVT relies on metal on metal friction, I figured it's a limitation of the belt/chain and CVT cones being able to apply enough pressure to hold the power. But you're making it sound like it's that pesky torque converter all along? :)

05 LGT 16G 14psi 290whp/30mpg

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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Oh, it was in some PDF Powerpoint thing. I think the safety margin was whatever the expected max torque was plus like 20% extra. I don't suggest you go tuning it, but I meant generally speaking it had beefier parts compared to the regular Gen2. I think the HT-CVT is kind of based off the Gen1 TR690 and has some meatier internals as well, especially the converter.

 

Try this, looks like the slideshow's not up there:

 

https://webcache.googleusercontent.com/search?q=cache:3mARPzobf-QJ:https://www.atra.com/Webinars/Import/Subaru_Lineartronic_CVT_Introduction.pdf+&cd=1&hl=en&ct=clnk&gl=us

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Which CVT is rated for ~430 Crank TQ? The high torque ones used in the WRX, 3.6L, and Ascent?

 

Since CVT relies on metal on metal friction, I figured it's a limitation of the belt/chain and CVT cones being able to apply enough pressure to hold the power. But you're making it sound like it's that pesky torque converter all along? :)

 

The number at the end is apparently (or was originally) the rating of that CVT’s core bits in NM input torque after the torque converter. That appears to have later changed to the footprint of the transmission though, as they have a “HT” version of the smaller one. They may have just limited the TC multiplication though.

 

The belt/chain can hold more power than most are pushing. The issue revolves around having the pully clamping force respond properly when you up the power, and having the TC lock up to prevent input torque from getting too high. This is why FXT’s eat CVT’s when tuned to levels that’s WRX’s are fine at, even though they have (more or less) the exact same CTV mechanically. The FXT tune just never clamps the cones tight enough to prevent slip.

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Core bits are good for ~580nm input torque. So "Yes", but only if your boost only happens when the TC is locked.

 

Same issue we had with the 5EAT: it's not a mechanical issue. TCU code needs to be reverse engineered to really make it survive.

 

So the answer is No.

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