danzick Posted September 1, 2011 Share Posted September 1, 2011 so i have a 3 speed automatic and it drives me nuts:horse: so im trying to atleast get as much power as possible from this car. i use it mostly for interstate driving, and it involves a steep hill i have to climb twice daily. its pretty much wide open on the interstate just to keep in in the range of 65 to 70. thats of course going up a steady incline, but not very steep. just noticeable that its up hill. so far mod wise, i have deleted both of the cats, i deleted the EGR, i made my own intake set up, with a cone filter. yes it has a heat shield , cleaned the MAF sensor, ran lots of seafoam through it, made sure all my vacuum lines were good, put a filter on the pvc breather so its not sucking oil through the intake, my fuel filter is good, brand new coolant temp sensor, brand new plugs and they are currently a perfect cardboard color, doesnt use a drop of oil or smoke at all, and i just calculated its getting 24.5 MPG. isnt that a little low? i see other posts of 28+ Quote Link to comment Share on other sites More sharing options...
danzick Posted September 1, 2011 Author Share Posted September 1, 2011 oh and might i add its an 88 GL-10 with the SPFI injection. i was having major white plug problems and it would randomly die and not start again, so i went to the junk yard and got an entire new throttle body top that included all the sensors and the injector and it runs much better now. Quote Link to comment Share on other sites More sharing options...
Red92 Posted September 1, 2011 Share Posted September 1, 2011 Pumping up your tires a bit more will help lower rolling resistance. I'm not sure if any of the special low-rolling-resistance tires are available in the Subaru sizes, but narrower tires would help as well. Depending on how you use the vehicle, you can also improve performance & economy by shedding weight. Some of these can get a bit extreme for a daily driver, but if you only use it for a commute vehicle, they may be tolerable. Things like removing the air conditioning system, removing the rear seats, removing carpeting, etc. Even just running with the gas tank half empty is good for 50 lbs! Keep it at 1/4 or less, and that's 75 lbs of extra weight you are not hauling around all the time! If you have a roof rack, you can remove the cross pieces to be more aerodynamic. You could probably drop another 15+ lbs by downsizing the battery. Quote Link to comment Share on other sites More sharing options...
Dj7291993 Posted September 1, 2011 Share Posted September 1, 2011 so i have a 3 speed automatic and it drives me nuts:horse: so im trying to atleast get as much power as possible from this car. i use it mostly for interstate driving, and it involves a steep hill i have to climb twice daily. its pretty much wide open on the interstate just to keep in in the range of 65 to 70. thats of course going up a steady incline, but not very steep. just noticeable that its up hill. so far mod wise, i have deleted both of the cats, i deleted the EGR, i made my own intake set up, with a cone filter. yes it has a heat shield , cleaned the MAF sensor, ran lots of seafoam through it, made sure all my vacuum lines were good, put a filter on the pvc breather so its not sucking oil through the intake, my fuel filter is good, brand new coolant temp sensor, brand new plugs and they are currently a perfect cardboard color, doesnt use a drop of oil or smoke at all, and i just calculated its getting 24.5 MPG. isnt that a little low? i see other posts of 28+ Get rid of that automatic. Switch it to the 5-speed manual. If you don't know how to drive one, learn. With that engine, that will give you the best boost in power and economy. My engine (carbed) ain't in great shape, and it went from 17-18mpg with the auto to 22+mpg with the manual. You notice a big difference on hills and passing people, and the overdrive will make a big difference in highway economy. The swap isn't very hard, and the tranny was only $100 at my local U Pull and Pay. You also need the pedals, flywheel and clutch, the hill holder or some other return spring setup (I just cut the lines and tied the thing up, you really just need the return spring function), mounts, bolts, and if it's 4wd, you'll need the front half of the drive shaft, and the rear diff (if you don't use 4wd, this doesn't have to be immediate, just do NOT put it in 4wd, or you'll have fun getting it out). It's really not that hard, and I think it will give you what you're looking for. Plus, those 3-speeds aren't known for their reliability. Quote Link to comment Share on other sites More sharing options...
danzick Posted September 1, 2011 Author Share Posted September 1, 2011 Oh ya im sure the 5 speed is a world of difference but I need this car daily so a 5 speed conversion isn't going to happen for awhile. As for removing things; I would die without air conditioning on the interstate. I ofcourse have to shut it off to climb any sort of hill but I need it:rolleyes: . And I want to keep the car somewhat nice inside so I wont be removing any carpet or seats. I do have 175 tires tnat are completely bald instead of 185s. Not my choice its just what came with it. Any other little things I can do to help? Maybe synthetic oils? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 2, 2011 Share Posted September 2, 2011 so i have a 3 speed automatic and it drives me nuts:horse: so im trying to atleast get as much power as possible from this car. i use it mostly for interstate driving, and it involves a steep hill i have to climb twice daily. its pretty much wide open on the interstate just to keep in in the range of 65 to 70. thats of course going up a steady incline, but not very steep. just noticeable that its up hill. so far mod wise, i have deleted both of the cats, Cat delete is only effective if you can use the extra flow and/or they are clogged/broken, etc. i deleted the EGR, Innefective i made my own intake set up, with a cone filter. yes it has a heat shield , Bad idea. The stock intake is not in any way a restriction and was already a CAI. You have likely lowered performance with your new intake. cleaned the MAF sensor, ran lots of seafoam through it, made sure all my vacuum lines were good, Seafoam is also pretty useless. put a filter on the pvc breather so its not sucking oil through the intake, How exactly did you plumb this? It is very easy to disrupt proper PCV flow and foul your oil with unremoved blow-by gasses..... my fuel filter is good, brand new coolant temp sensor, brand new plugs and they are currently a perfect cardboard color, doesnt use a drop of oil or smoke at all, and i just calculated its getting 24.5 MPG. isnt that a little low? i see other posts of 28+ Yes - your mileage is low. Should be about 27. Get a new O2 sensor. GD Quote Link to comment Share on other sites More sharing options...
tallwelder81 Posted September 2, 2011 Share Posted September 2, 2011 the great thing about lighter battery isnt just the overall weight savings, its also in the EXTREME front corner. so lighter battery means better weight distribution. i dont know if it rains much where you are, but a lighter gas tank seems to make my rig kinda scary in hydroplane situations. good riddance to A/C, air cond is lame. not only does it add a lot of pointless weight, it creates drag on the engine, EVEN when it is off. dump that s.o.b. and you wont miss it. Quote Link to comment Share on other sites More sharing options...
danzick Posted September 3, 2011 Author Share Posted September 3, 2011 Cat delete is only effective if you can use the extra flow and/or they are clogged/broken, etc. Innefective Bad idea. The stock intake is not in any way a restriction and was already a CAI. You have likely lowered performance with your new intake. Seafoam is also pretty useless. How exactly did you plumb this? It is very easy to disrupt proper PCV flow and foul your oil with unremoved blow-by gasses..... Yes - your mileage is low. Should be about 27. Get a new O2 sensor. GD hm. after i did all that stuff i went from 20 to 24.5 mpg. and my air filter was new and the cats wernt even plugged. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted September 3, 2011 Share Posted September 3, 2011 drive 60 instead of 65? O2 sensor sounds like a good idea. do your brakes and make sure the caliper slides are cleaned and regreased as well as drum return springs are properly operating. i've seen mileage go up 1-3 mpg after quality brake jobs (not just pad slapping it). i've seen no difference with using synthetic oils in XT6's, i wouldn't put the money there. i've swapped rear diffs, front diffs, and engine oils....no change. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 3, 2011 Share Posted September 3, 2011 There are plenty of people getting 27 to 29 MPG without any of your "mods" so that alone proves they were not the cause. You are still at well below the normal range for mileage. Hell - I can get 28 mpg from a later 90's Outback with 165 HP and bigger wheels/tires! GD Quote Link to comment Share on other sites More sharing options...
danzick Posted September 4, 2011 Author Share Posted September 4, 2011 gotta remember this thing has like 70 hp, and im floored. the interstate driving im doing is all up hill, so its floored to to keep 60 to 65.after deleting the cats and the air filter mod, i noticed a good increase in wide open power. maybe the cats were a little plugged i didnt really look. the body has 255 thousand miles on it. motor has been rebuilt about 15 thousand ago so its running good. and are you sure i can get 27 mpg wide open on the interstate with a 3 speed automatic? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 4, 2011 Share Posted September 4, 2011 (edited) The SPFI EA82 makes 90 HP. Plugged cats could have been an issue but it's unlikely on an SPFI rig. The stock airbox/snorkel/filter system has been flow benched by a prominent member here and IS NOT A RESTRICTION so it is not possible that you got any gains from it. You probably got a net loss because you are now pulling in warm engine-bay air rather than cold air from the wheel well. The additional sound has probably tricked your brain into thinking it's faster - you are not the first to beleive he got power from a CAI. All you are really accomplishing is extra noise and the possibility of hydro-locking your engine if you go through a deep puddle. As a general rule Subaru intake's are very good and will easily handle more power than you are making. They simply are not a good place to focus time/money as you will gain nothing. Yes - I am positive you can get 27 on the interstate doing 60. In fact it should be closer to 29 with the SPFI doing interstate runs. Have you changed the O2 sensor yet? If you have to keep it floored to do 60 - something is seriously wrong with your engine. That's the power level of my lifted hatch - which DOES have a 74 HP engine, 8" of lift, and is running 31" swampers. I would be checking your timing - both valve and ignition. SPFI EA82's are not *that* underpowered. What you describe is what how I expect people to be describing their lifted EA powered rig or an EA71 automatic, etc. GD Edited September 4, 2011 by GeneralDisorder Quote Link to comment Share on other sites More sharing options...
danzick Posted September 4, 2011 Author Share Posted September 4, 2011 up hill? it cruses at 70 on flat ground like nothing. maybe 1/8th throttle on flat ground to do 70 75. like i said. im up at 5000 feet, and its all an up hill battle. semis are going like 45 up these hills. the interstate driving from livingston to bozeman montana is far from flat or downhill. Quote Link to comment Share on other sites More sharing options...
Red92 Posted September 5, 2011 Share Posted September 5, 2011 If you have a roof rack, you can remove the cross pieces to be more aerodynamic. Adding a bit to my previous post, I found this thread about the mpg gains from removing the roof rack: http://ultimatesubaru.org/forum/showthread.php?t=61744 Quite a few reports of 2, 3, even 5+ mpg difference when removing the rack. :cool: Quote Link to comment Share on other sites More sharing options...
danzick Posted September 5, 2011 Author Share Posted September 5, 2011 Removing this will give me 3 mpg? Hard to believe Quote Link to comment Share on other sites More sharing options...
maozebong Posted September 5, 2011 Share Posted September 5, 2011 port the heads and intake. there is a REAL mod you can do, with real gains. also, egr is used to lower combustion temperatures. if you block it, the ecu doesnt know it and will waste gas. make sure ignition and valve timing are okay. get only ngk v-power plugs, and gap .005-.010" larger than spec. waste another 40 bucks on an accel superstock coil... i have an spfi ea82 that i dyno'd myself to make 77hp to the wheels. i also get easily 25 mpg on the highway with 29" tires, and loads more mileage with the stock size tire. but i also know the tricks of the trade you can put a high quality synthetic grease for the bearings to decrease rolling resistance, along with the axle cups, and increased tire pressure. i personally use almagard 3752 from LE. its special order and $430 a case. im lucky the race team i work for pays for it Quote Link to comment Share on other sites More sharing options...
danzick Posted September 6, 2011 Author Share Posted September 6, 2011 how does it lower combustion chamber temps when its coming in hot? thats why for my diesel they sell an egr cooler cause the exhaust coming back in is hot? Quote Link to comment Share on other sites More sharing options...
6 Star Posted September 6, 2011 Share Posted September 6, 2011 Removing this will give me 3 mpg? Hard to believe Looks like you already have them removed. Quote Link to comment Share on other sites More sharing options...
maozebong Posted September 6, 2011 Share Posted September 6, 2011 how does it lower combustion chamber temps when its coming in hot? thats why for my diesel they sell an egr cooler cause the exhaust coming back in is hot? is your EA82 diesel? no? well, then the same theory doesnt quite apply. not to mention, your ecu is not programmed to run without it, and can cost mileage especially at light throttle cruising. http://en.wikipedia.org/wiki/Exhaust_gas_recirculation#EGR_in_spark-ignited_engines Quote Link to comment Share on other sites More sharing options...
soobenthusiast Posted September 6, 2011 Share Posted September 6, 2011 i made my own intake set up, with a cone filter. yes it has a heat shield , This does lower performance, but I know some vehicles definitely get better mileage with a warm air intake. http://en.wikipedia.org/wiki/Warm_air_intake Plenty of stuff about them on ecomodder and high mpg sites as well. Quote Link to comment Share on other sites More sharing options...
danzick Posted September 6, 2011 Author Share Posted September 6, 2011 i dont think its really a "warm air intake" here is what i did. ok i put an adapter on the MAF sensor to put a cone filter on it. than, i built a big heat shield that goes from the shock tower, to past the canister for the fuel tank.i cut a round part in it so that the intake tube fits around it. than, i cut a big hole in my fender so that i could stick the bottom part of the filter on it so its sucking air from the inner fender. after driving it, i can pop the hood and the filter and adapter on the cold side of the shield feel somewhat close to the outside temp. on my 04 duramax, if you touch the filter after driving it, it will practically burn you its so hot. does it feel like i gained a lot of power? no it doesn't. but it definitely didnt make me loose any MPG and i like the louder sound lol. Quote Link to comment Share on other sites More sharing options...
maozebong Posted September 6, 2011 Share Posted September 6, 2011 warm air intake is moreso the part of running coolant through the intake manifold on "wet flow" intakes because fuel vapor wont condensate on the intake walls. Quote Link to comment Share on other sites More sharing options...
dennyt Posted September 6, 2011 Share Posted September 6, 2011 (edited) Pull the power steering pump, drain the rack & plug the lines, and get shorter belts (Alternator 7420, AC 7365 for my SPFI 5spd). Seriously. This is a cheap and easy mod that will free up HP and increase mileage. These cars are light enough to parallel park with one hand without power steering, and the road feel is better at speed. Also, ditch the clutching fan if your car has one, and replace it with a second electric fan. More free HP / mileage. And put your cats back on, scofflaw! Edited September 6, 2011 by dennyt Quote Link to comment Share on other sites More sharing options...
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