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subdoug

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    Carbondale Colorado
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  1. Then I guess the advice I keep seeing about purchasing your gas early in the day when it is coldest so you get a little more for your money is incorrect.
  2. Great no cost/low cost idea! If you saved 4mpg and drove 20K per year, at $3 gas you might have saved about $235. If you improved by 3-6mpg, may I ask what kind of driving do you mostly do with the 86 wagon? Is it mostly highway? A low cost/no cost mod I always do is remove the AC belt for the winter months, which is quite a few months here in Colo. But since you are supposed to occasionally circulate the freon in the winter, when I do winter maintenance on the cars I put the belt back on temporarily and run the AC for a bit. Re mpg I have no idea if this saves anything, and would be suspicious of any calcs I do because gasoline density is higher in the winter.
  3. Sorry, I wish I knew the hwy speed that was referenced. The generalizations came from tirerack.com in a section that addressed tire rolling resistance. Re the pwr req'd statement above, I believe the equation is F (force) = M (mass) X V <SUP>2</SUP> (velocity squared). I think what you are trying to say is that the force acting upon the vehicle (as wind resistance) increases with the square of the vehicle velocity. In layman's terms, double your speed, and you'll have four times the wind resistance. This is why the cartalk guys Click and Clack say to roll your windows up and turn on the AC (if needed) if you are driving above 40mph. The obvious behavioral mod for increased mileage is to slow down, but this is not always practical. The obvious structural mods for hwy driving would be do whatever is practical to reduce turbulence and induce laminar flow around the body of the vehicle. Robm, I'm impressed with your mileage figures. The most I've every been able to squeeze out of my EJ22 95 legacy is 33 mpg, and that was the trip I took where I put the automatic in neutral and coasted down some hills that were several miles long. I've often wondered if that coasting could damage the transmission, so I asked a guy at a transmission shop once. He advised against it at high speeds...said the trans wouldn't get enough lubrication. Was he right? Can anyone tell me how to get html code turned on so I can type in a simple velocity squared??? Html is listed under vB code, but doesn't seem to work.
  4. Here's some info I've dug up which should help with decisions re mods for better mileage (both behavioral mods and vehicle mods): 1st Case Scenario- Stop and go city driving vehicle energy use: 45% driveline friction 35% overcoming inertia(could be higher if stop sign @ every block) 15% tire rolling resistance 5% air drag 2nd Case Scenario- Steady Highway Driving energy use: 60% air drag 25% tire rolling resistance 15% driveline friction Thus removing an unused roof rack might make a significant difference to the highway driver, but would never be noticed by the guy who just tools around town. The "townie" might want to consider running synthetic gear lube in both his front and rear differentials. I would welcome anyone who wants to contribute any suggested vehicle mods given these scenarios. Given the above, my original idea about converting the 95 legacy to 2wd would only be of benefit if I drove around town alot, which I don't.
  5. Now I see I've opened an interesting thread with my original post. Unfortunately some have gone hopelessly off topic, behavioral mods being confused with vehicle mods. I could write the book on behavioral mods and gas mileage. My number one pet peeve is the guy in the diesel truck who floors it when the light turns green, pushing a lot of unburned fuel right out the exhaust. Pet peeve number two is the guy who drives all over the parking lot, trying to find the parking spot closest to the front door. I like to pull in and grab the first spot available, even if it means I have to walk a little. I give myself bonus points if I don't have to back out of the parking spot. Triple bonus points if I can exit the lot timed so I make the next green light, without having to accelerate rapidly. In addition to driving sensibly, I think the behavior mods which give the best mileage involve reductions in vehicle inertia changes, avoiding transitional behavior. Keeping the vehicle rolling at a steady pace. Enuf on that. Perhaps driving behavioral mods warrants it's own thread. Back to the vehicle mods. 91Loyale, thanks for your suggestions. I keep the engine in good tune, change air cleaners often, check the pcv valves, run good platinum plugs and so on. I have been wondering about aftermarket plugs vs original subaru plugs though. I assumed if O2 sensor was malfunctioning I would get an obd code, but maybe that's a bad assumption. Grossgary: I haven't tried synthetic fluids (in trans, differentials, engine) yet but I anticipate that the reduction in friction would be worth a try. Have been worried about syn in engine oil though as other vehicles I owned in past always started leaking at the seals when I tried synthetics like Mobile 1 back in the eighties. Anybody have experience running syns in their +100K miles subarus without developing leaks? Also Gary, I think the tire changes are an excellent idea... reducing the rolling resistance. I have been thinking about this one for some time now, and since I drive pretty sensibly I am more than willing to sacrifice handling for better mileage. Seems to me the legacy/outback tire footprint is way too wide. I'll have to consult with a tire expert for recommendations. Consumer Reports measures rolling resistance on their dynamometer when they test all-season radials, and the best performers were Michelins and some of the Japanese mfgrs. Torxxx, I took a close look underneath today, and it looks pretty easy to remove the rearmost propeller shaft, leaving the front in place which would secure the transmission spindle. Don't see any easy way to remove the rear diff though. The sticky problem is those rear drive axles. I did a quick test with the prop shaft disconnected, and there does seem to be quite a bit of friction when I rotate the rear prop shaft, making the rear wheels turn. I guess my arms just don't generate much hp! I did drop an auto trans from one of my subs recently and I must say it really is heavy. Unfortunately in my family fleet (4 running and two for parts) we only have one manual trans. I'll try and avoid the auto trans in the future. I've heard the clutches don't last on these cars but I suspect that is due to driving habits. My brother has about 190K miles on his original clutch in his 97 Outback SW. Enuf rambling... tnx for all the great posts. Keep the thread alive, and as I perform "mileage mods" I'll report on the progress. -Doug (aka subdoug)
  6. Any recommendations on good obd2 code readers for 95-99 series of legacies/outbacks? Tnx!
  7. My Sub collection is 95-97 outbacks and legacies. I am interested in mods to improve gas mileage, specifically converting to 2wd during non-winter months. 1. There is a 2wd fuseholder under the hood. Info on how this works from various dealers is vague and contradictory. If fuse is added (to convert to 2wd mode) will this stop the propeller shaft from turning? One dealer said this 2wd fuse should always be installed when the donut spare tire is installed on either of the back wheels. Does this mean in this mode you could run different sizes of tires on the rear? 2. If 2wd mode doesn't stop the propeller shaft from rotating, is there any way to disconnect/remove the propeller shaft so only front wheels are driving and fewer drive train parts are involved? I started to disconnect the propeller shaft on one, and realized that the short shaft from the back of the auto trans can fall out and leak trans fluid. Any way to keep that shaft from falling out?
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