Notices
RX-8 Discussion General discussion about the RX-8 that doesn't fit in one of the specialty forums.

Better mileage?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 07-21-2007, 11:19 AM
  #1  
Registered User
Thread Starter
 
MonkeyBoy88's Avatar
 
Join Date: Jul 2007
Posts: 19
Likes: 0
Received 0 Likes on 0 Posts
Better mileage?

What are some proven ways to get better fuel mileage? I've heard there are some intakes that can improve mileage, like the Rev-i. What about the other brands? How much of an improvement have you noticed? Also if you went with a larger diameter tire, lets say 245/45/18, would you get better mileage? Anyone try this? You would probably accelerate slower but a tenth or two might be worth it if you got another 2 mpg.
Old 07-21-2007, 11:33 AM
  #2  
Extraordinary Engineering
 
DarkBrew's Avatar
 
Join Date: Oct 2005
Location: Burls On
Posts: 4,733
Likes: 0
Received 12 Likes on 9 Posts
Constant speed driving has the biggest impact. Avoid traffic. Use highways.
My Catback system seems to have hurt my mileage a bit.
I have stock intake.
You can also take a board and screw it under your gas pedal.
Old 07-21-2007, 11:51 AM
  #3  
Registered
 
ken-x8's Avatar
 
Join Date: Aug 2006
Location: Northern Virginia
Posts: 5,027
Likes: 0
Received 5 Likes on 5 Posts
Google "hypermiling." Then ask yourself if this is really what you bought an RX-8 for.

Ken
Old 07-21-2007, 12:42 PM
  #4  
Extraordinary Engineering
 
DarkBrew's Avatar
 
Join Date: Oct 2005
Location: Burls On
Posts: 4,733
Likes: 0
Received 12 Likes on 9 Posts
hypermiling, LOL.
Old 07-21-2007, 06:08 PM
  #5  
Mu ha.. ha...
 
Razz1's Avatar
 
Join Date: Aug 2004
Location: Cali
Posts: 14,361
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by ken-x8
Google "hypermiling." Then ask yourself if this is really what you bought an RX-8 for.

Ken
That's after you screw a board under the gas pedal.


Old 07-21-2007, 06:18 PM
  #6  
I4NI
 
Silver_Surfer's Avatar
 
Join Date: Jun 2006
Location: Hawaii
Posts: 833
Likes: 0
Received 2 Likes on 1 Post
It is what it is. Sorry

Ever think about getting a Vornado or Turbonator?(Joke!)


I did that board under the gas peddal back in highschool The block came out within an hour
Old 07-21-2007, 06:28 PM
  #7  
meh.
 
deadphoenix52's Avatar
 
Join Date: Oct 2006
Location: fwb, fl
Posts: 1,658
Likes: 0
Received 0 Likes on 0 Posts
ride a bike
Old 07-21-2007, 07:23 PM
  #8  
THE BITCH IS DEAD
 
skhmund's Avatar
 
Join Date: Sep 2005
Location: Dayton, Texas
Posts: 236
Likes: 0
Received 0 Likes on 0 Posts
its called cruise control my friend, i cruise at 65 n im gettin 24 mpg
Old 07-22-2007, 12:14 AM
  #9  
1.21 Jiggawatts
 
Stavesacre21's Avatar
 
Join Date: May 2006
Location: Lima, OH
Posts: 1,330
Likes: 0
Received 0 Likes on 0 Posts
Ironcally, I always used to say that highway, cruise control miles yielded the best milage. However, i'm in a really odd situation now where the last 6 fill ups of in-town driving have been 18.5-19MPG but yet the last full tank on the highway was barely 21MPG.

The kick in the butt? I have finally started to leave the revs between 2.5-3.5 RPM's and run it up to 7-8K more frequently.

Don't ask. I have no idea. But honestly, that crappy highway MPG is starting to get to me. Why would it be like that?!
Old 07-22-2007, 12:18 AM
  #10  
Registered User
 
Rems31's Avatar
 
Join Date: Sep 2006
Location: Mississauga, ON
Posts: 2,080
Likes: 0
Received 3 Likes on 3 Posts
Always fill the 3 passenger seats with friends, family members or hobos. When traffic hits, turn off the engine and tell the passengers to get out and push.
Old 07-22-2007, 01:42 AM
  #11  
Senior Member
iTrader: (1)
 
8 Maniac's Avatar
 
Join Date: Oct 2005
Location: Aki City, Japan
Posts: 3,814
Likes: 0
Received 1 Like on 1 Post
Originally Posted by skhmund
its called cruise control my friend, i cruise at 65 n im gettin 24 mpg
but all those school zone tickets will cost about as much as filling up with normal driving
Old 07-22-2007, 01:45 AM
  #12  
Registered User
 
kevinD1226's Avatar
 
Join Date: May 2007
Location: Lowell, Mass
Posts: 414
Likes: 0
Received 0 Likes on 0 Posts
i read several posts where people have boosted their rx8s and noticed increased gas mileage i really dont see how that works out but id love to know
Old 07-22-2007, 02:19 AM
  #13  
13BEAST
 
mikeferz42's Avatar
 
Join Date: Mar 2007
Location: Union City, CA
Posts: 207
Likes: 0
Received 0 Likes on 0 Posts
i have the revi intake and it doesn't affect my fuel consumption in any way. i averaged about 18 mpg before the revi and i still get the same after installing it.
Old 07-22-2007, 10:21 AM
  #14  
Banned
 
4me2's Avatar
 
Join Date: May 2007
Posts: 768
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by MonkeyBoy88
What are some proven ways to get better fuel mileage? I've heard there are some intakes that can improve mileage, like the Rev-i. What about the other brands? How much of an improvement have you noticed? Also if you went with a larger diameter tire, lets say 245/45/18, would you get better mileage? Anyone try this? You would probably accelerate slower but a tenth or two might be worth it if you got another 2 mpg.
Try this, https://www.rx8club.com/rx-8-discussion-3/no-more-detonation-%2Amiac%2A-121249/

Pre-mix also.
Old 07-22-2007, 10:32 AM
  #15  
2007 BB RX8 GT
 
TheKDog's Avatar
 
Join Date: Sep 2006
Posts: 333
Received 1 Like on 1 Post
I've started towing my car with my truck.

It uses much less gas now.
Old 07-22-2007, 10:31 PM
  #16  
Registered
 
costello's Avatar
 
Join Date: Jan 2006
Location: Orlando, FL
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Stavesacre21
Ironcally, I always used to say that highway, cruise control miles yielded the best milage. However, i'm in a really odd situation now where the last 6 fill ups of in-town driving have been 18.5-19MPG but yet the last full tank on the highway was barely 21MPG.

The kick in the butt? I have finally started to leave the revs between 2.5-3.5 RPM's and run it up to 7-8K more frequently.

Don't ask. I have no idea. But honestly, that crappy highway MPG is starting to get to me. Why would it be like that?!
I've noticed this too about the 8 which I find too be different than other vehicles. My 2000 Honda Prelude got 22 city and 27-29 highway which is pretty much what the EPA sticker had. I'm also getting 18-19 city and 20-21 highway in the RX-8. Was hoping to get more when getting on the highway, but I think you have to keep the revs lower (i.e. around 3k) which means slower highway cruising. I'm usually cruising around 70-80mph on the highway. Even though the Prelude and the RX-8 run at the same RPMs in top gear (4000 rpms at 80 mph), once you go past 3k in the rotary, I think the mileage really starts to drop.
Old 07-22-2007, 11:58 PM
  #17  
1.21 Jiggawatts
 
Stavesacre21's Avatar
 
Join Date: May 2006
Location: Lima, OH
Posts: 1,330
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by costello
Even though the Prelude and the RX-8 run at the same RPMs in top gear (4000 rpms at 80 mph), once you go past 3k in the rotary, I think the mileage really starts to drop.
but on the contrary, they were performing completely different cycles at that RPM. No doubt, that would be more harsh on the prelude's wear and tear!

and you are right about one thing...once you reach 3750, the secondary ports open which definetely will drop your milage.

Even more ironic yet, I cruise at 70MPH on highways, which reads 72MPH on the speedo (1.6 MPH slower then what it reads), and that sits at RIGHT about 3650-3700. I always figured that I was barely missing the point at which the port opens...but maybe not. hmm.

Glad to see someone else has similar city/HW situation then me tho!
Old 07-23-2007, 12:11 AM
  #18  
Vtak just kicked in yo!!
iTrader: (1)
 
Renesis07's Avatar
 
Join Date: Jun 2007
Location: Lake County IL
Posts: 4,053
Likes: 0
Received 0 Likes on 0 Posts
the K & N drop in helps a very little bit. instead of getting like 19-20 highway, i get like 22-23 when Im not driving like a complete bat-out-of-hell.
Old 07-23-2007, 12:20 AM
  #19  
Registered User
Thread Starter
 
MonkeyBoy88's Avatar
 
Join Date: Jul 2007
Posts: 19
Likes: 0
Received 0 Likes on 0 Posts
So you're getting 2 to 3 mpg improvement with just a drop in filter? That's pretty good! Anyone else get the same results?
Old 07-23-2007, 12:55 AM
  #20  
13BEAST
 
mikeferz42's Avatar
 
Join Date: Mar 2007
Location: Union City, CA
Posts: 207
Likes: 0
Received 0 Likes on 0 Posts
i am not advising for anyone to do this in any way, but on an episode of mythbusters on the discovery channel, they have proven drastic reduce in drag by 'tailgating' a big rig. i think they managed to save 30% off their normal fuel consumption by drafting the big rig within 5 feet, which is milliseconds of reaction time.
Old 07-23-2007, 08:46 AM
  #21  
Vtak just kicked in yo!!
iTrader: (1)
 
Renesis07's Avatar
 
Join Date: Jun 2007
Location: Lake County IL
Posts: 4,053
Likes: 0
Received 0 Likes on 0 Posts
yea, its called drafting, and it works if you dont mind getting about 10000 miles worth of rock chips on your front bumper in about 10 seconds.
Old 07-23-2007, 08:48 AM
  #22  
Registered
 
Michael's Avatar
 
Join Date: May 2005
Location: Houston
Posts: 456
Likes: 0
Received 0 Likes on 0 Posts
Watch mythbusters. +1 for drafting, if you don't care about your bumper or have a bra.
Old 07-23-2007, 08:50 AM
  #23  
He's as bad as Can
 
expo1's Avatar
 
Join Date: Feb 2004
Location: Manchester, NJ
Posts: 4,309
Likes: 0
Received 2 Likes on 2 Posts
Drafting, and other tips are mentioned HERE
Old 07-23-2007, 08:57 AM
  #24  
Vtak just kicked in yo!!
iTrader: (1)
 
Renesis07's Avatar
 
Join Date: Jun 2007
Location: Lake County IL
Posts: 4,053
Likes: 0
Received 0 Likes on 0 Posts
lol, why are you guys suggesting drafting!!! its all fun until people start break checking you!!!! But then you use your 238 hp to go around them and run away!!!
Old 07-23-2007, 09:30 AM
  #25  
Registered User
 
Mysturji's Avatar
 
Join Date: Jul 2007
Location: UK
Posts: 16
Likes: 0
Received 0 Likes on 0 Posts
Sorry to break it to you like this dude, but if you're after fuel economy, you bought the wrong car!
However, if your low-fuel warning light has just come on, and it's 50 miles to the next service station, the following might help:
Don't use the engine to slow down. That's what the brakes are for.
Try not to use the brakes.
At 1000 RPM in 6th gear, you'll be doing 20 MPH. Always use the highest gear you can.
Accelerate slowly, if at all.
Lower speed=lower fuel consumption.
Try to keep a steady speed. (If you have cruise control, use it, except...)
When going downhill, put it in neutral or press firmly on the clutch.

Using these techniques in my previous car (Saab 93 SE Convertible 2L turbo) I averaged 33-34 MPG. Without these techniques, I got 28-30 MPG.
In my RX8, I usually get 24MPG. Using these techniques, I get 25MPG :o/


You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Better mileage?



All times are GMT -5. The time now is 06:21 AM.