best grounding points for an EJ20t?

[wagonofdoom]

so i see the threads fo hte USDM motors

but where are the best for the JDM counterparts?
WHen i come to a stop with my headlights and hit the brake my stereo resets, its really annoying. and when i hit my brake lights the headlights dim a bit



id like to throw a grounding kit on, but i cant find info ont he JDM stufffs

[Reason]

Sounds like a weak alternator. As for the grounds it shouldn't be much different (if at all) from the US Legacy.

[wagonofdoom]

yeah i thought that too.
just haent had a chance to slave one in.

[Reason]

Ok I can't find the thread but off the top of my head Alternator, intake manifold, strut tower, radiator support, fender next to battery, tranny and engine block. I have a sheet with the points and resistance somewhere. When I find it I'll post it up if nobody else does.

[Airgne]

also one on your turbo. this area makes alot of static. when i did it to my 180 i noticed a diff in idle and power.

[A1Fiddler]

Where do you ground on your turbo?

[wagonofdoom]

compressor splitline bolts im guessing
or tho the manifold


is 6 gauge big enough? or too big

[Airgne]

mine had 4gauge. when i did it to my 180 i had in on the intake elbow.

[wagonofdoom]

yeah reason if you get a chance post up that diagram and i will make a how to thing for it using it.

4gauge is kinda big. i use that as grounding wire for stereos normallly on low power setups.

[Reason]

Wow 8 or 6

[Airgne]

4gauge is big? wow that the size of my pericing and it looks small to me.

[Grafton]

i am using 8 ga for engine bay grounding but 4 or 6 ga. thats some heavy duty wire for reinforcing stock grounds

[wagonofdoom]

yeha im gonna end up goign 6 gauge


hey reason, whats up with the diagram?

[Reason]

Yes I found it, I have to type it all out since I can't find it on NASIOC. All credit goes to that mystery member. He wrote it up for his 98 GT. Give me a little bit so I can do it right, try to clean it up a bit.

[Reason]

Ok here it is

KEY

[AC] - Alternator Case
[MG] - Main Ground point on back of engine
[BA] - Negative terminal of BAttery
[IM] - Intake Manifold
[DF] - Driver's Front side above headlight on radiator support
[DS] - Driver's Strut tower
[PF] - Passenger's Front on ABS motor bracket
[PS] - Passenger's Strut tower

Results of ground to ground using a DVM for DC voltage.


[AC]->[MG] 7.0mv
[MG]->[BA] 7.3mv
[MG]->[IM] -1.9mv
[MG]->[DF] 11.0mv
[MG]->[DS] 11.0mv
[MG]->[PF] 9.6mv
[MG]->[PS] 11.5mv

Two points of interest:
The negative reading on the [MG]->[BA] "circuit" tells me that, on this car, the Intake Manifold is a better grounding point than the Main Ground point.
The body of the car gets its ground from an 8 gauge wire running from the "-" of the battery to the ground point on the radiator support. When I disconnected this wire from the firewall the results are the same as pulling the negative terminal off the battery.

I used 8 gauge wires to make the following grounds:
[MG]->[IM]
[MG]->[BA]
[BA]->[DF]
[MG]->[DS]
[MG]->[PS]
(I ran out of wires and couldn't do the [MG]->[PF] run)

Here's my results:

[AC]->[MG] 7.0mv (not regrounded)
[MG]->[BA] 3.8mv
[MG]->[IM] -1.7mv
[MG]->[DF] 4.6mv
[MG]->[DS] 5.2mv
[MG]->[PF] 7.6mv
[MG]->[PS] 5.0mv

I expect to see [MG]->[PF] drop more once I ground it. I'm also looking to run a wire from the alternator case to the main ground point, but I'll have to figure out how to attach to the alternator first.

Initial impression is that the car runs smoother, quieter, and seems more "effortless" when accelerating and cruising. Additionally, the lights seem a bit brighter and the car turns over quicker when starting. Overall a low-buck, low-effort mod that seems to have a few positive results with no apparent negatives. Time will tell.

Credit goes to the NASIOC member who wrote this

[wagonofdoom]

got a picture of the main ground?
i didnt see anything except the ground on teh middle of the engine by the alternator that runs to the back right of hte engine bay. maybe an 8 gauge wire