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Old 02-25-2008, 11:45 PM   #1
littlebhatia
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Default 320 miles per tank

Ok normally 260mpt, so that is the background.

I put a Group A TBS
A Blitx Nur Spec S Axel back (which by the way is a perfect fit on a 07 2.5i)
I have a thule rack with all the attachments
Stock everything else.

The TBS got me 20 miles more per tank and more power.
The exhaust pushed me from 280 to 320 mpt. The sound is straight authoritative, but still chill if you want to be low key.

But the real question is: What is the speculative amount of horsepower gain. I was thinking 2 from the TBS and 5 from the exhaust. Anyone else have the same setup with the same results? If so I would like to hear from you.

Peace
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Old 02-26-2008, 02:41 AM   #2
pondomoto
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i get 360mpt around town and up to 400mpt on the highway cruising w/ 55mph speed limit (doing 65 )

My Setup:
Borla Headers
Cobb Cat Back
Rallitek 02 Sensor Extender
Cobb Cold Air Intake
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Old 02-26-2008, 03:00 AM   #3
rivman05
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hey guys, what is a TBS? im new to subs, but ive never heard of a tbs, I used to work for Ford. Any ideas on how to get more mpt out of an older soob??? I have a 95 imp wgn. Any ideas much apprecitaed since im not gettin good milage at the moment. im getting about 15-16 in town with a 2.2. THanks again.

Gabe
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Old 02-26-2008, 03:14 AM   #4
PA-Outback2000
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tbs = throttle body spacer.
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Old 02-26-2008, 10:17 AM   #5
zavier
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Quote:
Originally Posted by littlebhatia View Post
Ok normally 260mpt, so that is the background.

I put a Group A TBS
A Blitx Nur Spec S Axel back (which by the way is a perfect fit on a 07 2.5i)
I have a thule rack with all the attachments
Stock everything else.

The TBS got me 20 miles more per tank and more power.
The exhaust pushed me from 280 to 320 mpt. The sound is straight authoritative, but still chill if you want to be low key.

But the real question is: What is the speculative amount of horsepower gain. I was thinking 2 from the TBS and 5 from the exhaust. Anyone else have the same setup with the same results? If so I would like to hear from you.

Peace
then i think you my friend are seeing the largest MPG gain in the history of cars with a TBS hahaha...i call bull and you are just driving different but that's just me.

As for the HP...you gained nothing but sound from your axleback because the pipes coming off the engine are still the same diameter and are not doing anything different. changing the tip does nothing. so if you want to claim 2hp (which is almost not even measurable because it falls within any +/- on a dyno) then go for it but i wouldn't believe for a second a standard axleback did anything.

currently i have an injen SRI and a stromung catback and i drive my car like i stole it (as i say cars should be driven haha) and i see 300+ mpt on every fillup and that's pre-amber light coming on to tell me i need more fuel...i drove to toronto and back (not going to disclose speed but it was above the limit posted) and i was seeing ~26mpg...so i don't think it was your TBS that did that.
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Old 02-26-2008, 01:45 PM   #6
SilverSubie2.5
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Originally Posted by zavier View Post
then i think you my friend are seeing the largest MPG gain in the history of cars with a TBS hahaha...i call bull and you are just driving different but that's just me.
Well, he claims the TBS got him an extra 1.25 mpg, which I suppose is believable, maybe. What gets me is, 2.5 mpg from an axleback? THAT is where I raise the BS flag.
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Old 02-26-2008, 02:06 PM   #7
zavier
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Originally Posted by SilverSubie2.5 View Post
Well, he claims the TBS got him an extra 1.25 mpg, which I suppose is believable, maybe. What gets me is, 2.5 mpg from an axleback? THAT is where I raise the BS flag.
haha that is true i think i just looked at the total number and attributed it as coming from the TBS...but either way you look at it those 2 parts together are not going to increase your mpg that much if at all.
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Old 02-26-2008, 02:11 PM   #8
Gso2k
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I get 350 before my reserve light comes on, almost every time. I think we have a 2gallon reserve right guys? (+-.xx) So Im thinking my overal range is something like 400mpt. Does that sound like a tad too much?
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Old 02-26-2008, 02:13 PM   #9
Calamity Jesus
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Please.. never post 'miles per tank' again in relation to fuel efficiency.. it means nothing unless you run your tank dry.

Miles per gallon... a 'tank' isn't a unit of measure.
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Old 02-26-2008, 02:39 PM   #10
zavier
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Originally Posted by Gso2k View Post
I get 350 before my reserve light comes on, almost every time. I think we have a 2gallon reserve right guys? (+-.xx) So Im thinking my overal range is something like 400mpt. Does that sound like a tad too much?
i don't know about a reserve but the light comes on with about 2gal left in the tank (i think it's 2gal) and the manual says i wont turn the light off till the tank has at least 4gal. I believe what it came down to is you can go ~40-50mi after the light comes on (at least i know i've done over 30miles after the light came on cause i was stuck on the QEW in Toronto with no way to get off lol)
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Old 02-26-2008, 04:01 PM   #11
GFimpreza
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Originally Posted by Beaverboy View Post
Please.. never post 'miles per tank' again in relation to fuel efficiency.. it means nothing unless you run your tank dry.

Miles per gallon... a 'tank' isn't a unit of measure.
Thank you!
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Old 02-26-2008, 04:48 PM   #12
06OutbackSport
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The best "mpt" I've gotten was 410, all highway. That fill was 13.6 gallons and that works out to be 30.1mpg... not too shabby. In the winter I'll generally a little over 300 miles between fillings (same 13 gallons per fill). That works out to be about 23 mpg... again, not that bad, considering I let my car warm up a few minutes every morning and do much less highway driving.

I've also got a Group A TBS coupled with a Cosmo SRI. The SRI's been on for about a year, but the TBS just got put on about 6 weeks ago. I didn't do an ECU reset on either and noticed slightly less mpg with the SRI (probably due to the change in driving style more than anything else... that sound is incredible!); but I have noticed a consistent increase of 1.0-1.5mpg per tank every fill since I've had the TBS on there.

Can't wait to see what it's like in the summer.
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Old 02-26-2008, 05:18 PM   #13
LTracer
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Originally Posted by 06OutbackSport View Post
I've also got a Group A TBS coupled with a Cosmo SRI. The SRI's been on for about a year, but the TBS just got put on about 6 weeks ago. I didn't do an ECU reset on either and noticed slightly less mpg with the SRI (probably due to the change in driving style more than anything else... that sound is incredible!); but I have noticed a consistent increase of 1.0-1.5mpg per tank every fill since I've had the TBS on there.
For the record: adding bold on modifications such as a CAI/SRI and not resetting the ECU is a horrible idea. The purpose of resetting the ECU is to erase all the learned values (timing, fueling, etc) that were based on your previous setup. The ECU will eventually relearn the new intake overtime but it's not recommended. Start from scratch (aka reset), let the ECU figure out whats going with 10 minutes of idling (primarly fueling), and then try out your new mod.
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Old 02-26-2008, 06:22 PM   #14
ZRS
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So yeah this one time I got 200 mpt and I was like wtf?!?! Then I realized that my tank was still half full. OMG!!
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Old 02-26-2008, 08:24 PM   #15
Patrick Olsen
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Quote:
Originally Posted by Beaverboy View Post
Please.. never post 'miles per tank' again in relation to fuel efficiency.. it means nothing unless you run your tank dry.

Miles per gallon... a 'tank' isn't a unit of measure.
Amen, brother!

Quote:
Originally Posted by 06OutbackSport View Post
... again, not that bad, considering I let my car warm up a few minutes every morning...
You're not doing your engine any favors by doing that.

Quote:
Originally Posted by LTracer View Post
For the record: adding bold on modifications such as a CAI/SRI and not resetting the ECU is a horrible idea.
I'm not sure I'd go so far as it to say it's a "horrible idea," it just isn't optimum. You're not going to hurt anything if you don't reset the ECU.

Quote:
Originally Posted by LTracer View Post
The ECU will eventually relearn the new intake overtime but it's not recommended. Start from scratch (aka reset), let the ECU figure out whats going with 10 minutes of idling (primarly fueling), and then try out your new mod.
Not recommended by what or by whom? And why 10min? Why at idle? Wouldn't I want to drive the car to let the ECU "re-learn" the fuel maps?

Pat Olsen
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Old 02-26-2008, 08:33 PM   #16
Gun
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I have borla headers and a 2.25" stromung catback. i average around 25mpg driving spiritedly. No tbs though. Ill have to look into that.
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Old 02-26-2008, 11:39 PM   #17
Eyedoc Orlando
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I normally get 26-27mpg combined cycle with my highest avg fuel economy using Shell gasolines. Just FYI

and yes, mpt = terrible. I've never had the balls to drive my car to where the gas light came on, I always chicken out at the 12.7 gallons used mark when it hits the last line on E.
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Old 02-27-2008, 12:24 AM   #18
pondomoto
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if im not mistaken, a tank and a gallon are both units of liquid measure...
if the tank is 15 gallons, then 400mpt = 400miles/15gal = 26.7mpg

yet i do find it hard to believe that everyone runs their tank dry

when i used mpt i was considering the fact that i usually wait for the light to turn on or damn close to that before i fill up... my .02

(Yes mpg is better)
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Old 02-27-2008, 12:32 AM   #19
rougeben83
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^^^ Simple, they don't. The "E" on most tanks usually has about 1/8th or so of the tank still in reserve so schmucks can have enough gas to get to the closest station.

Get a full tank, drive around, note mileage, fill up tank to full again, note how many gallons it took.

Divide mileage by gallons and you get MPG. One "empty" tank reading can vary as much as a 1.5 gallons from another "empty" reading. Of course you'll think you got more mileage.

BTW, its not good for the fuel pump to keep the tank running constantly to dry. The gasoline actually helps it stay cool.
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Old 02-27-2008, 12:53 AM   #20
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Well you guys are crazy, I get about 19 miles per if I really pull my foot out of the gas I'll get around 23, thats the highest I have received.
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Old 02-27-2008, 09:19 AM   #21
bobko
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Quote:
Originally Posted by rivman05 View Post
hey guys, what is a TBS? im new to subs, but ive never heard of a tbs, I used to work for Ford. Any ideas on how to get more mpt out of an older soob??? I have a 95 imp wgn. Any ideas much apprecitaed since im not gettin good milage at the moment. im getting about 15-16 in town with a 2.2. THanks again.
The usual things will get you better gas mileage in a Subaru. Make sure your tire pressure is where it should be. Make sure you have a clean air filter. Change the oil with a good synthetic. Make sure your brakes aren't dragging. If it's time to replace the tires, get new ones that have a pressure rating of 44 psi and run them at 40-42 psi. Check the car for excess weight and dump what you can. (Lots of people have loads of junk in their cars, most of which can be dumped.) Have a test done to see if your catalytic converter is clogged. Aging O2 sensors can cause a car to have reduced gas mileage, so think about replacing your O2 sensors. (Your car should have two -- one before and one after the catalytic converter.) These are the basics that you can do in any car.

Once you do that, consider getting a higher-flow intake, including something like a K&N air filter. A monster sound system will rob a couple of horsepower (at full volume, anyway) and add considerable weight, so keep the sound system simple if you want the best mileage. Date skinnier women. If winter gasoline is sold in your region, understand that you will get worse gas mileage with winter gasoline.

I have a 1995 Legacy wagon (manual trans and 2.2 engine) and regularly get 24-26 mpg in typical driving. I've gotten as high as 30 mpg on the highway but I usually get 25 mpg for a week of commuting, which is a mix of a little stop-and-go and some highway driving.

--Bob
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Old 02-27-2008, 09:36 AM   #22
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Agree that Miles Per Tank or relying on the fuel gauge as a measure are both highly inaccurate and unscientific. Also running the gas tank dry will damage the fuel pump (gasoline is used to lubricate and cool the in-tank pump). Idling or warming the engine is also a waste of fuel and harmful to the engine.

The only way to measure accurate MPG is to fill up. Drive a known route at a known time of day until the tank is getting low. Fill up (ideally same pump, same time of day, same ambient temperature and air pressure, car parked same place, same payload in car...) reset your trip meter and/or take note of the odometer reading. Drive the same known route, same time of day, same traffic etc... until the tank is getting low again. Refill the tank (all same as above). Take note of the gallons needed to fill and how many miles driven since last fill. Miles divided by Gallons = MPG. Repeat all steps and average the results over time.
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Old 02-27-2008, 11:50 AM   #23
Bluefoton
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..not miles per tank again..
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Old 02-27-2008, 12:01 PM   #24
LTracer
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Originally Posted by Patrick Olsen View Post
Amen, brother!


You're not doing your engine any favors by doing that.
I would beg to differ on the allowing to let your engine warm comment as a blanket statement. In northern climates (MN for example) when you cold start at -20F the oil is so damn cold and thick that it needs to warm up a bit for proper flow. Ever tried pouring oil at -20F? In my opinion allowing the engine to idle a bit under very little load while the oil starts to properly lubricate is better than immediately taking off under driving load with a bunch of thick oil at the bottom of the oil pan. I'd venture to guess the latter is worse for engine internals. My .02$, I'm open to criticism though so feel free to .

Quote:
Originally Posted by Patrick Olsen View Post
I'm not sure I'd go so far as it to say it's a "horrible idea," it just isn't optimum. You're not going to hurt anything if you don't reset the ECU.
I stand corrected , you won't 'hurt' anything pursay, but you won't achieve optimum fuel economy / performance until all your old long term learning values are overwritten with new data. It's not recommended by me or any reputable tuner that understands how the ECU works. It is an opinion statement though and I acknowledge that. If you just want to bolt on a intake and don't care how it immediately changes performance / economy than go for it.

Quote:
Originally Posted by Patrick Olsen View Post
Not recommended by what or by whom? And why 10min? Why at idle? Wouldn't I want to drive the car to let the ECU "re-learn" the fuel maps?
When you first restart after resetting the ECU you'll be in OL for a few minutes (likely varies between models/conditions for me personally it's 2-3 minutes). During this time the ECU isn't really learning anything (check LTFT with logging). Once it finally transitions to CL and tries to hit lambda the AFR will bounce around for a bit as it balances MAFv / AFR readings. Keep in mind this learning encompasses more than modifications to the car, LTFT's also attempt to compensate for aging components and sensor degradation as best as possible. Why not just start driving right away? The first time I reset and drove right away without any learning the car died at the first stop light. Again, it is an opinion statement, howevever I'd like to see supported justifications for not wanting to let the ECU relearn.
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Old 02-27-2008, 05:28 PM   #25
rougeben83
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Originally Posted by fgummett View Post
Agree that Miles Per Tank or relying on the fuel gauge as a measure are both highly inaccurate and unscientific. Also running the gas tank dry will damage the fuel pump (gasoline is used to lubricate and cool the in-tank pump). Idling or warming the engine is also a waste of fuel and harmful to the engine.

The only way to measure accurate MPG is to fill up. Drive a known route at a known time of day until the tank is getting low. Fill up (ideally same pump, same time of day, same ambient temperature and air pressure, car parked same place, same payload in car...) reset your trip meter and/or take note of the odometer reading. Drive the same known route, same time of day, same traffic etc... until the tank is getting low again. Refill the tank (all same as above). Take note of the gallons needed to fill and how many miles driven since last fill. Miles divided by Gallons = MPG. Repeat all steps and average the results over time.
Well what's interesting to me is how the mpg can be easily affected by different variables. I notice I lose about 2mpg or so during the winters because they switch the gas to 10% ethanol for example...
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