TOPIC: 2003 Subaru Legacy Wagon 2.5L

Hello All,

I'm joining you all here from New Hampshire. I am new to the family, as I have purchased a personal license program and have finally Grooved my vehicle after a successful test with my push mower (gaining 15% fuel efficiency and a noticable power increase).
I have spoken with Ron in great detail about various aspects of what it is we strive to accomplish, as well as TracyG now too. Prior to Grooving my TB, the plugs were gapped, and the ohm resistor installed on my post Cat O2 sensor. An attempt to install a resistor on my AIT temp sensor proved to be the wrong resistance, as I continued to receive error codes. This has been removed, and is my next project, likely to be taken on this evening.
In my first attempt at grooving my TB, I made a mistake, I had the business card in my TB when Grooving, leaving the Groove too far from the plate, for a cable driven TB. I admit this, as this was a learning point. The car had noticable power gain, not much, but I was able to notice an increase in the power. The car also smelled, as Ron shares, like a drier vent, warm, and moist, no hint of exhaust fumes. Even in the wrong spot, the Groove is proven!
For round two, I filled my Groove using JB Kwik, and let set. Then I began to groove with the plate closed. Up until the last two cuts to cut the groove, things were great. Then it went awry.
I should offer some info before I continue to let you know how the process unfolded in front of me. Ron has touted about using liquid to make the cut, and tells us how it helps to keep the bit cool. I agree with this, it is important to keep your bit cool, prolonging it's life. The other part to that is that the liquid lubricated the bit's edge, and helps it slide through the material you're cutting. If you use oil, the bit cuts much cleaner, and stays cool as well. Some folks offer info saying they keep water handy as this cools the bit as well. Any liquid will cool the bit, and oil is no different. Oil cools a little slower than water, as the conducting properties of water are much higher than oil. Water has little to no lubricating properties, so even though you are cooling your bit, you are not aiding in the edge longevity, and may not be doing it as much good as you might think. Oil, cools the bit and keeps the edge sharper longer, depending on material cut of course. The oil also doesn't cause undue hardening, that may be happening to your bit with water. The faster something is cooled down from a high temperature, is relative to the hardness of the material afterward. This is measured with the Rockwell Hardness Test. If you cool something too quickly, it becomes very hard, good right, well not if the hardness sacrifices your durability. The harder something is, the more brittle it's tendency. You have a hard bit to begin with, being that it is carbide. The next hardness for effectiveness and durability is diamond coated, for production. Other materials are out there, but for cost purposes and production are not realistic. So the thinner the oil, like PB Blaster, which Ron has recommended, the better the cut, vs. water, and because it's thin, it offers cooling that is effective, and does not compromise hardness:brittleness of the bit.
So I've wandered, back to my point. The second Groove that I made, was good until the next to last cut. This is when i noticed the seperation and pulling out of the JB Kwik. The problem I found, was the PB Blaster was so proficient at pentrating, not just the metal for cutting, but it made it's way between the JB Kwik and the TB, causing seperation. I finished the cut and removed the JB Kwik that was in the old Groove. After properly cleaning the Groove with carb cleaner, and wiping it out with a clean rag, so as not leave any oily residue, a new batch of JB Kwik was applied to both old and new Groove(one WIDE Groove now). I had teh time, and allowed the JB Kwik to set over night. Fearfull of a repeat, I opted not to cut the filled in Groove with oil. As it was just JB Kwik, the temp range was going to be minimal, and of little threat to the integrity of my bit.
I have reconditioned the ECU, and noticed a greater gain in power in the throttle, and the exhaust is still clean. I am currently on the same tank of fuel that I filled after completing the ECU conditioning process. I have really put the Groove through it's paces as I returned from a trip to visit family, and went up and over a known truck route/ mountain pass. This is a good test of the efficiency, and my car already has noticible gains and reduction in consumption. The power was nice, in the first few portions of the pedal movement, but even up a hill, the transmission had to drop to maintain speed. Once the transmission was in the appropriate gear, letting off of the throttle was easy as the power was there to maintain constant speed, even increase at times, with not further pedal action. A nice side effect to fewer emissions.










Thank you for your time, as reading this has taken plenty of it. Thank you Ron and Tracy for your time, and knowledge.

Justus

Nice work!

Did you cap the PCV valve and increase the spark plug gaps?

I'm new to, exciting stuff eh?!

Cheers
Rino (NZ)

Justus, thanks for sharing your experience here, it's valuable info! Perhaps a lesson about re-Grooving thru JB, I might use water when cutting JB, and PB or cutting oil for metal.

I enjoyed our conversation, and thanks for the pics!

Tracy G

Rino,

To answer your questions, I did cap the PCV valve, and gap the plugs. The initial gapping of the plugs was a remarkable over gapping, which gave surprising results. The mfg spec for plug gap for my vehicle is .044, and I had put the gap out as far as .070. I had no noticeable sluggishness, and the vehicle sounded fine. I drove it that way for about two weeks, and noticed zero gains. However, when the nipple on the TB, where a tube from my PCV valve connects to (as my PCV valve is not on my TB), was capped, I noticed increase in power, and an increase in mileage. Due to worn components on my vehicle, I will be replacing my O2 sensors as soon as they arrive in the mail. I have over 150K miles on the current sensors, and referencing Ron and his new video plus our conversations, O2 sensors are rated for 50K before they degrade and cost you efficiency, without queuing a check engine light.

Tracy,

I will take your recommendation under advisement regarding water with the JB. Always a pleasure.

For everyone,

On my way into work today, at a half tank, my mileage is at 195. This is impressive. In the past at this point I have been at 200 miles. This would leave me disappointed, except for the fact that my trip home this past weekend, took me up and over a mountain, with additional RPMs to maintain speed. With the Groove in place, the required fuel to maintain those RPMs and speed is definitely reduced. I would have been near 1/4 tank, or just above, before the Groove with the speeds I navigate that all too familiar route with.

Justus

Hey Justus

Capping those vacuum drains will help every time eh?!

I put a new O2 sensor in my Daewoo and reset the computer. I did that post groove and that's when I started noticing better mileage straight away. Too early for proper figures but once I get my OBD2 Bluetooth unit, I can calculate usage on my android phone on the fly, can't wait! I'll post my results in due time.
Annoying those sensors cost about $150 here. Ah well, bankcard is the answer

My spark gaps (on the Daewoo) are big enough to hold my morning news paper LOL and I decided to leave them alone for now..

Cheers
Rino (New Zealand)

Rino,

The sensors I've ordered haven't shipped yet. I ordered them through a source I found online. Once the items arrive, I will install them, and hopefully they work without throwing any codes for check engine. I have read comments from unsatisfied customers, on similar generic brands with less than happy results, requiring them to opt for the pricey known brands. The generic brands were just under $27 US for each. Plus $11 for S&H. Not sure if they ship to your area, however, would be worth a shot. Once I install and run these units, I will share the link of the supplier. No point in putting it out there to frustrate folks and risk them wasting money. I will keep you informed. Always a pleasure,

Justus

WOW! Yes I would be very interested in that!

I just paid $140 NZ (about USD110) for mine
I guess the quality is always the flip side of the coin though...

Thanks for that Justus!

Cheers
Rino

To update everyone,

As of yet I have had no noticeable gains in mileage. The car runs smooth, quicker take off and more noticeable throttle response, as far as a 4 cylinder goes, and cleaner exhaust. But I'm frustrated by the lack of fuel economy gain.

So last night I took the TB off and plugged the idle air pathway, and drilled a 1/8" hole in the center of the plug. The car runs a lot quieter than before, and idles with foot on brake while in gear, at an impressive 550 RPM. When the car is in park, the idle is at 750. The tank was full last night, so results are yet to be measured for gains. Things seem to be good, or that's just my positive thinking/hoping.

I decided to reroute the tube from the PCV valve on the motor into the air box. I dilled a hole, inserted a 3/8" vacuum line splice and JB'd it. Everything is solid, and works fine.

Attached are pic of the projects.





The clearish barrier is wax paper, i filled the hole, covered with wax paper and set it on a flat surface. 4 minutes later I flipped it over, gently tapped on the plug, confirmed it was stiffened, and quickly pulled the paper off, much like a band-aid. The results were expected, no material stayed behind. Then I cleaned up the surface and edges of the TB, where the gasket comes into contact with the surface, with a sanding drum that comes with the Dremel kit.

Hey Justus, looks and sounds good. Sounds like your IAC restriction hole is about right size hole. If idle RPM is too low for A/C or cold start this winter, easy enuf to open the hole a tad. But I like the present idle RPM #'s

Ditto the PCV hose re-route to air filter box.

"Bout only other thing I can think of is the small vac. hose/hole in TB,to left of filled in IAC cavity, is that supplying vac. to something or is it EVAP purge from charcoal can./fuel tank? IF it's EVAP purge might re-route to before TB, ideally to close to where air inlet duct connects onto TB. Airflow will be higher speed just before TB, as opposed to just anywhere else in filter/duct assembly. Putting EVAP there will get a little bit of Venturi vac. effect to help draw fumes in. Capping/re-routing EVAP hose will improve manifold vac. just that much more...

But again, IF that small hose going to TB is the EVAP line. EVAP is near-certain to go to manifold vac. somewhere, might be worth tracking it down and re-routing. When I see a posted pic here of a TB and I see any little holes in bottom of TB I automatically ask "what's THAT for?"

Your and my Subaru wagons are a small engine/big car combo in relative terms. They need some coaxing to improve MPG. Being a Gadgetman means using imagination, so we use everything we can to get//increase results where possible. My Subie is a rolling test-bed of a number of applied technologies... Haven't tried a Magic Amulet yet, know a good Witch Doctor?

BTW, didn't see or I missed it, didja replace O2 sensor(S) yet. A look at what OBD11 datastream is showing for O2 sensor voltages and speed of how fast voltage is switching up/down would be very useful IMHO. I'd do a re-learn when new O2 is installed, but ideally I would want to see OBD11 #'s at each stage, before O2 install, after install before re-learn, then after re-learn. That might confirm things.

Doin' GREAT Justus, keep us posted thx for excellent pics!

Tracy G

That is a GREAT JOB, Justus!

Has anyone told you they loved you roday?

Update,

This past weekend was spent on doing repairs. My car needed new struts all around. And while I was under the car, I also had a chance to replace the O2 Sensors. The front sensor is working with no issues, and the rear, I will be returning for a replacement, as it is throwing two codes, indicating low voltage current to the sensor. As long as you are not in a hurry, Stylingtrucks.com has resources for inexpensive parts, to include the $26 US sensors I installed. Will let you all know once I replace the rear, if the part from these folks works, or if I have to bite the bullet and purchase the much pricier one.

I also replaced my sisters front struts, and had an opportunity to drive her '02 Subaru Forester, 5 speed. The difference between her throttle response and mine was night and day. Her's sets me back in the driver's seat when pressing the pedal. Her car has no groove. My car is snappier than it was, however it is no where as responsive as her car. Thoughts? Just buy a new (to me, used) car? I am noticing no gains in fuel eco yet, and am tempted to fill and regrouve the TB just incase I missed something. And my apparent lack of power, comparativley, has me concerned that there is something unseen and undiagnosed happening inside my engine. Is there a sensor (MAF, MAP) that give better throttle response that may be degraded? Any constructive criticism would be appreciated.

Justus

Well Justus, I'd sure suspect that rear O2 sensor, what kinda codes again?

Ya know it sounds like my '85 Subie, mine was always underpowered. IT's far better than before, but I'd love to have more! Find out what else is different between yours and her Subaru's..

I'd look at vehicle weight, trans. type and engine type comparing hers/yours.

My buddy in Phoenix had Ron Groove his '87 Subaru wagon same basic car as mine, BUT his was injected Turbo version mine lowly feedback carb w/ no turbo. I shoulda gotten a Turbo one, night/day diff. And the Groove gave my buddy a big power AND MPG boost as well, Ron video'ed him raving about it for minutes it's on Youtube Ron could hardly get a word in! I drove that Gray Subie days after Ron shot that vid it ran GREAT!

I've learned that w/ Subaru's-- shop around buy one w/ enough power to start, and the Groove will just Shine on THAT one!!

I'm thinkin' 'bout starting a new thread of all the various Tricks and small mods I've done to my Subie, I've thrown a lot at that car, and lately it's starting to show more power. Some easy/cheap, some real Project level stuff (Plasma Ignition).

Tracy G