What did improve the fuel economy for you?

Post by **dan777** » 13 Nov 2011, 15:08

Everybody is trying to save gas those days, so would be nice to share what it helped increasing your MPG.
Please choose what it really made a difference for you (obvious factors like: wind, road grade, driving style are not in the list)

Post by **FlyingVolvo** » 13 Nov 2011, 15:16

Honestly, I don't think anyone could notice a difference with any one of those things alone. Together, I do think they could make a difference.

I did these changes all around the same time

-Installed Cone filter (Amsoil Ea)
-Installed Snabb performance air intake
-Removed resonator, replaced muffler with performance Magnaflow
-Volvo Spark Plugs
-IPD HD Ignition Coils
-New MAF
-Removed bevel gear
-Removed roof rack cross bars
-Tires to 40 PSI

And I did notice about 32 MPG average of the freeway at around 69 MPH as opposed to 29 MPG typically. The AC in these cars sucks, and by that I mean it can suck a lot of power away. I get about 4-5 MPG less with the AC on. My car absolutely feels more powerful at temperatures below 40 degrees or so. Below freezing is even better, once you get into the turbo boost.

valvster · Post by **valvster** » 13 Nov 2011, 17:31

Noticeable increase in power and fuel economy by jamming the airbox flap constantly open.... measured by the hip pocket as my odometer is busted. Also removed a baffle thingy at the front of the intake to the airfilter box (no snow drifts in Sth OZ) but I doubt if that would have had a measurable effect.

Valvster

Post by **tjts1** » 13 Nov 2011, 18:10

Coroplast
http://farm4.static.flickr.com/3150/269 ... 11f1_o.jpg
http://farm4.static.flickr.com/3288/269 ... 6eb1_o.jpg
http://farm4.static.flickr.com/3245/268 ... eb75_o.jpg

Post by **rspi** » 13 Nov 2011, 19:31

Most of that stuff will tune the car but not really improve gas mileage. Of course if your wires or plugs are bad or badly worn, that'll help but if they are in normal condition, installing new will not really help.

The #1 thing that will help you get better gas mileage is HYPERMILLING. I'm not an extream hypermiller but your driving technique is likely the key. I use a Scan Gauge to monitor my mileage (http://www.ScanGuage.com). There is another product like it (33% the cost) called Ultra Gauge that does just about the same thing.

When I cleaned my PCV system my mileage actually dropped a little. Also, moving into the city hurt a little. When most of your trips are less than 10 miles, you'll never get better than 20 mpg, which should be considered good. I fixed a vacuum leak on my Jeep once that cost me about 3 mpg. Left me twisted and torn.

This is what I have done that I think helps me get good mileage:
- Run tire pressure 2 psi high.
- Installed K & N box filter.
- Use full synthetic oil.
- Use 93 (91+) octane.
- Use a scan gauge to change driving habbits.
- Do not let the car sit and warm up. Never recommended and a big waste of gas amoung other things.
- Use OEM plugs. They simply are the best. Most high quality plugs will cost you 1 to 3 mpg, some cost as much as 4 mpg.
- Slow down on the highway, especially on trips shorter than 50 miles. The time difference between going 55 mph and 70 mph is about 2 or 3 minutes on a 15 mile highway trip. However, that will cost you 25% in gas usage. Over a year that could be hundreds of dollars. I get 33 mpg at 55 mph and 26 mpg at 70 mph.

I figured that my changes have gotten me 15 to 18% better mileage. When I was driving 35,000 miles per year that was a big deal. Most people that have T-5R's don't get the mileage I do. I'm going to try cleaning my MAF to see if that helps.

I drive most of the time in S mode. Since I don't drive agressive most of the time I did not see a difference between E and S. The good thing about S mode is that my power is always at my foot if I need it. I actually think that the car shifts a little sooner in S mode from 1st to 2nd, to 3rd in the S mode. Maybe 2 to 3 mph sooner when driven lightly. Which probably saves a mpg. In my sedan I had I was getting 25 mpg around town and 29 on the highway. I get a little less with the wagon, especially since I moved into town. My move has saved me $50 per month in gas so I'm not complaining but maybe cleaning my MAF will help.

Another note: I was moving stuff in my car and really had it weighed down. The mpg difference was only about 1 mpg. I think the turbo makes a difference. A NA car may be a different story with weight in the car. I also could not see a difference in drifting, not to mention how dangerous that is.

Here is a link to a lot of chat about it on VF. http://volvoforums.com/forum/volvo-850- ... mpg-52856/

Maybe this can be stuck till gas goes back down under $2 per gallon. Don't hold your breath!

Post by **jblackburn** » 13 Nov 2011, 21:59

Honestly? Training your foot helps the most.

Look up my post "almost 40 mpg!". I got 33 this weekend from it on a 250 mile trip doing 70-75. Just accelerate pretty slowly and they're pretty decent on gas.

Post by **erikv11** » 14 Nov 2011, 00:49

Replaced leaky valve stem seals when I had the machine shop recondition the head: 4-5 mpg improvement, and no more burning oil.

Post by **rspi** » 14 Nov 2011, 09:12

jblackburn wrote:Honestly? Training your foot helps the most.

Look up my post "almost 40 mpg!". I got 33 this weekend from it on a 250 mile trip doing 70-75. Just accelerate pretty slowly and they're pretty decent on gas.

We get better mileage in our S70, a better final gear ratio. We usually get about 33 mpg in it as well.

axlaxl · Post by **axlaxl** » 14 Nov 2011, 10:49

Alignment made the biggest difference.

Lucas Fuel Additive i've noticed improves by about 10-15%

I also noticed a big improvement when I disconnected the Heat Riser hose. Not sure why but when it was connected my MPG went into the toilet.

arnabio · Post by **arnabio** » 14 Nov 2011, 15:49

ecbsykes wrote:...I did notice about 32 MPG average of the freeway at around 69 MPH as opposed to 29 MPG typically.

That's amazing to me. I keep hearing these kind of things from a few people with 98-00 V70 XC's. I can never seem to get mine much better than 25 with an all time high of 26. I measured these numbers by taking mileage divided by gallons in the next fill up, but either way, never any better than that. Did yo unnoticed any single one of those modifications that made a large difference?

My only other thought is that my transmission that's being rebuilt right now was on the slow road to failure for the 15k since I bought the car.

-Aaron