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2020 WRX Prototype (new pics)


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So the answer is No.

 

If you’re willing to opensource tune, it’s actually a tentative yes. The tables are available to tell the CVT what you’re doing. Presuming Subaru did the same as with the 5EAT transmissions they leave some headroom where if you tell the TCU that you are making more torque it can respond accordingly.

 

You’re not going to make 400whp with the high midrange torque spike that most go for, but 400whp at redline is only 440NM. Factoring in drivetrain losses and you’re right around it’s rated torque.Tune it for flat torque to redline, tell the TCU what you’re doing, and it should be fine.

Edited by utc_pyro
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If you’re willing to opensource tune, it’s actually a tentative yes. The tables are available to tell the CVT what you’re doing. Presuming Subaru did the same as with the 5EAT transmissions they leave some headroom where if you tell the TCU that you are making more torque it can respond accordingly.

 

You’re not going to make 400whp with the high midrange torque spike that most go for, but 400whp at redline is only 440NM. Factoring in drivetrain losses and you’re right around it’s rated torque.Tune it for flat torque to redline, tell the TCU what you’re doing, and it should be fine.

 

 

Any tuners out there doing that? Would be interesting to hear some experiences on that..

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  • 3 weeks later...

Subaru has also said they have designed the WRX STI for one specific market segment. In an interview recently with Motoring.com.au, Subaru’s WRX project general manager, Masuo Takatsu said the brand’s performance fans “simply aren’t interested” in an automatic in the higher output STI.

 

Takatsu went on to say, “At this point, we don’t have any plans to release an automatic version as STI customers tend to be more people that are into motorsports, and for those customer bases, we believe a 6MT (six-speed manual transmission) is the best choice.”

 

Amen to that.

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Subaru already released the STI A-Line with an automatic, so it's not exactly foreign territory for them.

 

The WRX S4 with a CVT in Japan is also a pretty decent seller.

 

I think they know that there are very few reasons that someone is willing to buy a new STI and part of that is that it comes with a manual.

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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.

 

 

 

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

 

 

 

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? :)

 

CVT does not rely at all on metal to metal friction, it relies upon the shear strength of the CVT fluid....

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CVT does not rely at all on metal to metal friction, it relies upon the shear strength of the CVT fluid....

 

You are thinking the Nissan Toroidal CVT, which actually has clutch like particles inside the fluid to provide friction and grip:

 

[ame=http://www.youtube.com/watch?v=5jIeSgq7ewI]Nissan Created The First Production High Torque CVT - YouTube[/ame]

05 LGT 16G 14psi 290whp/30mpg

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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Same for Subaru, the fluid is the friction material... if you had straight metal on metal contact, both the chain the variator surfaces would wear and fail...

 

Sure but that's the same as saying an engine would wear out without fluid, well duh.

 

Now a traditional metal CVT belt is smooth, thus there is plenty surface area friction modified fluid to work against. But Subaru's CVT belts are more like chains, and have teeth on them, thus a lot less area for the friction modified fluid to do it's work, thus they are more heavily relied on clamping.

05 LGT 16G 14psi 290whp/30mpg

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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I started watching that video and thought to myself there is no way thats working !

 

CVT's suck donkeys balls.

 

Stick with the 6MT and there is now conventional auto's in 8 speed anyway so I really don't know why they are wasting their time with CVT's in high power applications.

Edited by Tronic
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For the people saying subaru should produce a high performance wagon, look no further than the ford focus RS. People were clamoring for ford to bring this car to the states and when they did, barely anyone bought them, at least not at sticker prices. I'm starting to see more now as prices fall and dealers are left stuck with leftovers, but there just isn't much of a market sadly for these cars. Its the same reason subaru has not put much money into the WRX and STi. They just dont bring in enough money to warrant the huge R&D cost to develop them.

 

I sadly parted with my 08 Spec.B last month and replaced it with a V90 cross country. Hoping the next STi is something special because the plan is for the wife to take my V90 and I go back to a Subaru.

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The Ford Focus is a piece of shit. I'm having to work on a lower spec version and if thats anything to go by you wouldn't touch one. The Ford Mustang however now that its being made in RHD for our market is a sellout. If I had a choice of the RS and the V8 mustang, which are of similar price....its a no brainer, nobody looks twice at a Focus.
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Ford isn't known for doing the best cars here either. I'm not sure what attraction the Ficus had on people, but if it never appeared in the RS version it would probably only be for old people stepping up from a Fiesta.

 

 

As for the CVT, it's obviously depending on friction, and someone must have thought quite a bit around it to make it work. It was once considered for F1, but was banned before it got to race.

[ame=http://Www.youtube.com/watch?v=x3UpBKXMRto]Williams FW15C CVT - YouTube[/ame]

 

 

The CVT will however remove the skill of the driver knowing when to do gear changes, which is one part of the things that distinguish drivers on the track.

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For the people saying subaru should produce a high performance wagon, look no further than the ford focus RS. People were clamoring for ford to bring this car to the states and when they did, barely anyone bought them, at least not at sticker prices. I'm starting to see more now as prices fall and dealers are left stuck with leftovers, but there just isn't much of a market sadly for these cars. Its the same reason subaru has not put much money into the WRX and STi. They just dont bring in enough money to warrant the huge R&D cost to develop them.

 

I sadly parted with my 08 Spec.B last month and replaced it with a V90 cross country. Hoping the next STi is something special because the plan is for the wife to take my V90 and I go back to a Subaru.

 

 

Focus RS is a high performance hatchback with seats so skinny this middle-aged white dude, who has always loved small fast hatches/ coupes ('90 GTi 16v, '94 Corrado VR6) couldn't squeeze into it (whereas my GTi had some of the most comfortable Recaros I've ever sat in!), and the seats were so thick, there was like 4" of leg room when I had them all the way back, so no way my kids could sit behind me. They basically built a 4-door Camaro hatch. And then they wanted $40k for a car that people with family's can't really drive much. Plus, it had its issues. Well, at least that was the Focus ST, IIRC. After that, I didn't even bother looking at the RS. Same problem with the Mustang GT I sat in. If you're gonna build a car only 5'7" 150 lb people will feel comfortable in, don't be surprised when middle-aged guys with "dad bods" (I'm 6'1", around 225) don't want.

 

 

 

This is the main reason I'm looking at a Charger - about the only sedan left with some power and reasonable front and rear room. I'd LOVE me a new LGT, even with just a beefed up 5EAT or maybe the 7EAT from the Infiniti Q50 (they are cousins, and the new 7EAT can handle ~500 HP). I just need about 3-4" more rear legroom than the Q50 has (it's smaller than the LGT).

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I’ve driven a friends RS and it was a fun car.wouldni buy one, probably not, but either way it certainly makes for a good alternative to an STi, Golf R, etc.

 

Regardless of your opinion of the car all I’m saying is you can go back years and find people writing about how ford should bring he RS to the states and when they finally did, barely anyone bought it. That kind of reception certainly has an impact on other companies willingness to spend a ton of R&D money on a car with limited appeal to the masses in the US. If you want to use the mustang as an example, the GT350 haven’t sold well either. Part of that is probably from dealers marking them up, but it’s just another example why companies focus on cars for the masses and have a hard time justifying performance cars with a small customer base

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Sure but that's the same as saying an engine would wear out without fluid, well duh.

 

Now a traditional metal CVT belt is smooth, thus there is plenty surface area friction modified fluid to work against. But Subaru's CVT belts are more like chains, and have teeth on them, thus a lot less area for the friction modified fluid to do it's work, thus they are more heavily relied on clamping.

 

regardless of belt or chain, the fluid is the friction material, if you think otherwise, feel free to put regular hydraulic oil in there and see how far that trans goes.....it wont since the fluid does not have the required shear strength to hold the chain in place for rotation. This is why CVT cannot handle boat loads of torque..

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I'm not sure why you claim the fluid is the friction material, do you have any documentation on that?

 

 

As I see it the fluid has to be broken through to ensure contact between chain studs and discs while still not break through on parts where the lubrication is needed.

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Nils ... it's not worth it. Some people have some crazy ideas, and they can't see through to think rationally. But what can you do? :lol:

 

you know the best part about people talking too much?

 

https://content.subarunet.com/snet/_content/fixed_operations/oil_program/trans_fluids.pdf

 

 

they often are confused... Subaru states it is a friction material for the CVT

subarucvt.thumb.PNG.94b890e1592b4dd0a5b8dd39bda10bd2.PNG

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you know the best part about people talking too much?

 

https://content.subarunet.com/snet/_content/fixed_operations/oil_program/trans_fluids.pdf

 

 

they often are confused... Subaru states it is a friction material for the CVT

 

I did just come across this article: The effect of ZDDP in CVT fluid on increasing the traction capacity of belt‐drive continuously variable transmissions

 

Note that they say Belt-drive, aka smooth belt like Nissan uses, instead of chain-drive like Subaru does, but that could be semantics. Though even Subaru official calls their system a chain-driven type shown here at 3:06 and on:

05 LGT 16G 14psi 290whp/30mpg

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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Hey Dumbass, they say it has "excellent metal friction characteristics"

 

Which is NOT the same as a "friction material for the CVT"

 

Every material on the face of the Earth is a friction material.

 

Even the best lubricant will still be a friction material. But the best lubricant can also be described as having excellent metal friction characteristics if it helps protect your engine from wear.

 

:wub:

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Oils are actually pretty complex.

 

I have a new GSXR750 and the bike oils are now quite specific due to the clutch. Now the clutch is floating in oil so the specific oils do NOT apparently contain so called "friction modifiers", whatever the hell they are.

 

So essentially it has a 14,000rpm redline and makes any Subaru engine look pathetic but its still obviously sufficiently lubricated while screaming its nuts off, go figure.

Edited by Tronic
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"friction modifiers" used to be zinc compounds, but due to catalytic converters they are now other materials. They are designed to act as a last resort and will bind to slipping surfaces to protect them.

 

 

It's nothing new that motorcycle oils don't have friction modifiers. It has been almost as long as wet clutches have existed. But if you have a Ducati you usually don't have to worry about that since they have a dry clutch and you can have all friction modifiers you want.

 

 

Also watch out when you have limited slip differentials - they don't like friction modifiers either.

 

 

The 14k redline on a 750cc engine is not that surprising if you look at piston velocities, the 750cc engine has a speed of 75 fps (23m/s) at 14000 while the Subaru 2.5i engine at 6000 has 60fps (18m/s), only 20% slower even though the max rpm is 57% lower.

 

 

Then the bike is of course tuned and equipped for more power, but not optimized for fuel economy in the same way as a the car engine is.

 

 

The 750 definitely takes the price in this comparison with 200hp/liter over the 2.5i with 70hp/liter.

 

 

Anyway - when looking at the piston speed it's clearer that it's not that different when it comes to the lubrication issues.

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"Linear" m/s piston speeds are over simplifying things, but no point going into technical stuff on this forum. Needless to say pistons speeds are not related to loading and bearing surface areas etc etc. Sufficient to say if you want to pump out almost 150Hp from only a 750cc N/A 4 stroke engine without it blowing up in 5 minutes, things have to change radically. The whole engine starts requiring the precision and balance and material types found in a modern turbo.
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  • 2 weeks later...

Bugger the 2019 STi just looks to be a stop gap before they totally update it and the engine.

 

The S209 is available in such limited numbers it may as well not exist.

 

Looks like we will be waiting another 2 to 3 years for something exceptional that you can just walk into a showroom and buy.

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