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Been reading posts about creating new grounds from the Neg batt. terminal to certain spots in the engine compartment. This is supposedly supposed to reduce hesitation and increase smoothness of the engine. If I really haven't noticed any hesitation from the engine, is it still worth doing to improve the ECU's ability to monitor what the car is doing?
 

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From what I've heard from others, the mod is only really worthwhile if you have a piggyback chip like the Unichip. I have a TurboXS Stage 1 and my engine response improved considerably. It used to have a big flat spot right after the turbo kicked in in second gear. It's gone now.
 

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HKS GROUND SYSTEM

Im thinking about getting the HKS Earth Ground System, expensive but worth it. Anyone have or heard of it?
 

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Yep, my hesitation is all but gone after iv30's grounding mod handiwork. I have it on video, but I still need to capture it on my computer. All it takes is 8 ring terminals and about 20 feet of 8-gauge speaker wire. I spent more than I had to by getting rather expensive ring terminals...you can just get regular cheap ones at a hardware store. I got the speaker wire from a car audio store. It really shouldn't cost you very much at all.
 

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Re: HKS GROUND SYSTEM

Nexus6 said:
Im thinking about getting the HKS Earth Ground System, expensive but worth it. Anyone have or heard of it?
I'm with Verdugo, you don't need to buy a kit. Just go buy some good wire and ring terminals. That's all you'll need. No point is getting fancy with this type of "mod" (unless you want colored wires).
 

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can someone explain the actual physics/ scientific reasoning behind the grounding mod? i still dont get what it actualy does to help
 

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Basically When the ecu is taking a measurement from a sensor the value of that measurement can be altered if the ground potential at the sensor is different than the ground potential at the ECU.


on another note:

anyone out there w/ a new WRX notice that there arer lots of ground wires that look like they were added. I just notice lots of grounds that seem to be add ons (lots of electrical tape round the ends)

nick
 

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I know there was a thread on this subject before, but I just did the grounding mod yesturday and I noticed that my boost readings have increases from the regular .09mpa to .10mpa. Now I know there was discussion on if this is the result of more boost or just more accurate readings due to a well gounded system. I've also install the 3/16 connector mod. With these two mods that car seems to be running better and is a little more peppy. Any thoughts?

Thanks:D
 

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Penguinking said:
can someone explain the actual physics/ scientific reasoning behind the grounding mod? i still dont get what it actualy does to help
Computers can be easily confused when it comes to differences in "ground". Since the signals are usually based off of a "zero" point (not necessary literally zero), it is possible for the computer to get confused if the zero point is moving around. This would be caused by the ground drifting, which can be avoided by putting multiple grounds down to create a single large one. OK, I know that somewhat oversimplified, but I think you'll get the idea.
 

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WRXed said:


Computers can be easily confused when it comes to differences in "ground". Since the signals are usually based off of a "zero" point (not necessary literally zero), it is possible for the computer to get confused if the zero point is moving around. This would be caused by the ground drifting, which can be avoided by putting multiple grounds down to create a single large one. OK, I know that somewhat oversimplified, but I think you'll get the idea.
i'm starting to understand it

all the sh*t from physics class is comming back to haunt me, i'm starting to recall all that stuff!!!
 

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just to play devil's advocate for a moment....if this mod is really so cheap and effective why would subaru not do this at the factory? i personally believe it's all a crock of sh*t but i do have some extra 8 gauge and ring terminals left over from my sub amp install...so what the hell.....kinda like being agnostic and going to church as an insurance policy! :p
 

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mark5211 said:
just to play devil's advocate for a moment....if this mod is really so cheap and effective why would subaru not do this at the factory? i personally believe it's all a crock of sh*t but i do have some extra 8 gauge and ring terminals left over from my sub amp install...so what the hell.....kinda like being agnostic and going to church as an insurance policy! :p
I don't know for sure, but I only started noticing the hesitation after I got my unichip. From what I've read on I-Club, this mod only REALLY helps those of us that have unichips, since using only the factory ECU, you don't really notice it. I'd say that's why it's not already done at the factory :)
 

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mark5211 said:
just to play devil's advocate for a moment....if this mod is really so cheap and effective why would subaru not do this at the factory? i personally believe it's all a crock of sh*t but i do have some extra 8 gauge and ring terminals left over from my sub amp install...so what the hell.....kinda like being agnostic and going to church as an insurance policy! :p
Well if Subaru did it in the factory, that would be one less thing for us to tweak... Maybe it doesn't really work. Its like the old trick of installing a toggle switch not connected to anything.. when someone's in the car you flip and and say feel the difference? 9 outta 10 times they always say yes!
 

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exactly where do these grounding points go from the battery - there seem to be six - anyone who has made their own kit - where did you ground to?
 

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I ran 4 grounds...
1. to the drivers side strut tower
2. the drivers side manifold
3. the passenger side manifold
4. on the firewall behind the intercooler

I essentially looked for grounds from sensors under bolts and ran grounds there.

edit: This was my 69th post! Whoa hoa!
 

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Apparently many people on I-Club are syaing it doesn't work. I went through it and I think that there may be a "correct" way on how to proceed with the ECU(reset at the proper time).

Got the Unichip, had to reset the ECU during the installation since I unplugged the battery. Ran fine for 3 days then hesitation.

Waited for another week and installed one single 4 gauge cable to the intake manifold and reset the ECU. Didn't want to reset the ECU but messed around, lost the bolt behind the battery, etc...
After the car ran fine for 3 days and the hesitation started again.

A week later, reset the ECU, unplug the grounding mod cable and drove my car for 2 days until the hesitation came back. I got 1 more 4 gauge battery cable. Hooked another point on the intake manifold. And hooked now the 2 cables from the intake manifold to the battery WITHOUT resetting the battery. Everything worked great right away. And now, there is no placebo effect! I had my Wife noticing the hesitation several times, actually she asked me if there was something wrong with the car. She went for a ride again and I asked her if she now notices a difference and she told me she couldn't feel the hesitation. I will not lie, there is a tiny bit sometimes of hesitation when the car is cold. So it will be 4 days now. I will keep you posted in a week or 2. Or whenever the hesitations come back.

I'm not an engineer but a very practical thinking person: I believe after installing the Unichip, the ECU relearned and the car started to be jerky. Adding a grounding mod AND resetting the ECU makes the ECU relearn WITH another piece of hardware and eventually gives the jerkiness again. Adding a grounding mod without resetting the ECU somehow fools the ECU. Now, by writing this I completely understand that the ECU will eventually learn that grounding mod is "there" and start the hesitations again. We'll see. I really hope it can be fooled more or less.
 

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they dont tell you this for the same reason they dont tell you about the tire tread having to match so closely or it will dmaage or freeze your LSD!!!
bummin
DML
 
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