Go Back   EcoModder Forum > EcoModding > General Efficiency Discussion
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 09-28-2010, 01:36 AM   #1 (permalink)
EcoModding Lurker
 
Join Date: May 2010
Location: Oregon
Posts: 37

OregonOutback - '01 Subaru Outback
90 day: 27.97 mpg (US)
Thanks: 2
Thanked 1 Time in 1 Post
Subaru CVT vs 6-speed Manual

I am wondering which would be more ideal for hypermiling, a 6-speed stick shift, or a cvt. The base car that I am interested in (hypothetically) is a Subaru Outback with the 2.5l 4 cyclinder.

CVT:
Rated 22/29. Possibility for incredibly high gear ratios, but can you get it to drive in a high ratio?? Can you put it in neutral and coast? Probably would be better for cruising at 65mph with cruise control on, but would it be better all around?

6-Speed:
Rated 19/27. Much more control of the gear ratios. Even 6th isn't all that high of a ratio though, from what I recall reading somewhere. Could definitely coast and pulse/glide easily.

I currently have a 2001 outback with a 5spd stick, and I can regularly get 29-32mpg, and I'm still learning a lot from this site. I never get even close to the 21mpg city rating that my current car has. Would that likely be the case in the 6-speed too? To otherwise complicate my thoughts, on the subaru forums, many users with the new cvt seem to easily get into the mid-thirties, and from what I can tell, they aren't trying to get amazing gas mileage.

Does anyone have a newer outback with either of these setups? Anyone with a scangauge? Any other thoughts regarding one or the other?

__________________
New Cycling website: www.mybikespot.com
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 09-28-2010, 03:03 AM   #2 (permalink)
EcoModding Lurker
 
Join Date: May 2010
Location: Oregon
Posts: 37

OregonOutback - '01 Subaru Outback
90 day: 27.97 mpg (US)
Thanks: 2
Thanked 1 Time in 1 Post
2011 Subaru Outback:
CVT: 3.525- 0.558
Final drive 3.900:1

Manual 6 speed: 1st 3.454; 2nd 1.947; 3rd 1.296; 4th 0.972; 5th 0.825; 6th 0.695 Final drive 4.44:1

My current cars gear ratios:
1st: 3.45, 2nd: 2.11, 3rd: 1.45, 4th: 1.09, 5th: 0.87
Final Drive Ratio (:1) 3.90
__________________
New Cycling website: www.mybikespot.com

Last edited by bmwboarder; 09-28-2010 at 03:19 AM..
  Reply With Quote
Old 09-28-2010, 11:25 AM   #3 (permalink)
Left Lane Ecodriver
 
RobertSmalls's Avatar
 
Join Date: Aug 2008
Location: Buffalo, NY, USA
Posts: 2,257

Prius C - '12 Toyota Prius C
Thanks: 79
Thanked 284 Times in 197 Posts
The CVT has better ratios, but there's a lot more a hypermiler can do with a stick, including shifting to N and turning off the engine (or even leaving the engine idling). I'd get the stick for sure.

I would also point out that now may be a good time to downsize your vehicle. Have you considered an Impreza 5-door, Toyota Matrix, or a Honda Fit?
  Reply With Quote
Old 09-28-2010, 11:52 AM   #4 (permalink)
EcoModding Lurker
 
Join Date: Sep 2010
Location: Ovid MI
Posts: 45

Niner_xA - '05 Scion xA
90 day: 35.82 mpg (US)

Horse Hauler - '95 Ford F-250 XLT
90 day: 13.47 mpg (US)

Butterkup - '02 Mazda Miata
Thanks: 2
Thanked 8 Times in 5 Posts
I had a Dodge Caliber with the CVT. A CVT would be awesome for hyper milling... if you could reprogram the TCU. Unfortunately, you probably can't, so the TCU may end up fighting you. For example - if you pulse and glide, the engine will downshift slightly to match your attempt at acceleration. You can't really lock the transmission into a specific gear.

On the other hand, since it's got the complete range of input to output ratios, it can theoretically match the most efficient engine speed to the road speed and "assumed driver goal" ie acceleration, deceleration, cruising. I noticed when I turned on the cruise control the engine would drop RPMs since it realized that it was going for a steady state value.

This CVT was also not one of the ones with paddle shifters and preset "gears" that you can control - one of those might also be easier to control, like a manual transmission. You'd have some energy lost through the drive belt, I think.

Also, my drive belt started slipping shortly before I got rid of it. It would not have been a cheap repair.
  Reply With Quote
Old 09-28-2010, 12:11 PM   #5 (permalink)
...beats walking...
 
Join Date: Jul 2009
Location: .
Posts: 6,190
Thanks: 179
Thanked 1,522 Times in 1,123 Posts
...this posting harkens back to a lingering question I've had for years: "...which is more efficient, CVT or 6-SPEED?"

...I would assume the answer would be tied to the next question: "...where used, in CITY or on HIWAY?"

...is this due to the CVTs' seemingly: (a) rather 'poor' improvement over simple automatics or (b) due to poor 'application'?
  Reply With Quote
Old 09-28-2010, 12:35 PM   #6 (permalink)
Master of 140 hamsters
 
superchow's Avatar
 
Join Date: May 2008
Location: Lacey, WA
Posts: 183

Hamster - '07 Honda Civic EX
90 day: 29.41 mpg (US)

Whooshy Wagon - '04 Volvo V40
90 day: 23.33 mpg (US)

Minotaur - '09 Ford Taurus X SEL
90 day: 19.05 mpg (US)
Thanks: 1
Thanked 8 Times in 7 Posts
I recently test drove the 2011 Outback with the CVT. I am a stick-shift kinda guy all the way, and even converted my wife to preferring sticks - but this CVT felt great. It really depends what kind of driving you'll be doing. If you cruise the highways into the wilderness, then I'd stick to the CVT. If city driving is your bread and butter, the stick may yield better results.

I personally was in awe of the 1600-1700 rpm going 65 mph down the highway. 35 mpg is a realistic number at those rpms.

Plus, for the manual control aspect - the transmission comes with paddle shifters and a manual gate on the shifter. So anytime you need to "drop a gear", a flick with the left paddle and the CVT simulates a lower gear for engine braking.

I'd say test drive both versions and see what fits your needs better. Oh, and kindly let us know what you decided! BTW: an updated engine is coming to Subaru within the next year or so. They claim slightly better mileage...
__________________
  Reply With Quote
The Following User Says Thank You to superchow For This Useful Post:
bmwboarder (09-28-2010)
Old 09-28-2010, 01:07 PM   #7 (permalink)
EcoModding Lurker
 
Join Date: May 2010
Location: Oregon
Posts: 37

OregonOutback - '01 Subaru Outback
90 day: 27.97 mpg (US)
Thanks: 2
Thanked 1 Time in 1 Post
Good stuff, thanks everyone. That is pretty amazing to have a subaru under 2k rpms at those speeds. Right now I'm at 3000rpm at around 63mph...

I don't plan on buying a new car anytime soon, so I don't think I will test drive either one, I just enjoy looking at future technologies.

RobertS, I totally agree with you, a smaller car would be better, but we pack it full of camping stuff and go to the mountains too often to get by with a smaller fwd car, and my wife and I have decided to only own one car. I have read of a few people getting almost 40mpg in their outback though (on a full tank even), so maybe by the time I can afford a new one I could push it to 45mpg with some mods.

__________________
New Cycling website: www.mybikespot.com
  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Honda Insight - Replace CVT Transmission (with manual) Irons Hybrids 17 05-29-2015 11:05 PM
New CVT transmission electric-assist with electric assist Ptero Fossil Fuel Free 2 09-23-2010 10:41 PM
Honda CRZ hybrid 6 speed manual is coming! tjts1 Hybrids 19 01-18-2010 11:46 AM
CVT vs. Manual vs. Automatic? Nate General Efficiency Discussion 12 05-04-2009 12:07 AM
Synchros stuck in Geo Metro 5- speed manual trans buggywhip DIY / How-to 2 07-27-2008 10:52 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com