Helpful information on Grounds, VERY important


blinx9900

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i recently talked to Joseph Davies (wiring guru) about grounding points, he provided me with excellent info so i thought I'd post it in this thread, below is our conversation:

(6:14 PM 3/23/2008) blinx9900: sorry to bug but your the wiring guru after all, i have my ground like this: 2 from tranny to frame rail, 1 from back of valve cover to shock tower, is there a better way to do it?
(7:13 PM 3/23/2008) Joseph Davis: New unibody cars do a good job, but as these cars get older you see a LOT of weirdness. Partially due to engine harnesses rotting, ground straps rotting, unibody spot welds flex/crack slightly and create resistance.

The engine block is THE ground in the system, run everything TO it not to something that bolts to it or bolts to something that bolts to it; that being said the thermostat housing is a weird place to put the sensor ground for the engine. Think about it, aluminum bits that immediately form aluminum oxide (corrosion) with coolant flowing through part of it, and steel bolts that do the weird aluminum-steel corrosion thing. The OEM grounds are NOT what you want to follow, Honda only had to worry about 70-160whp for 3 years/36000 miles of warranty after that they could care less.

Anyway, I'd make sure:

- All wiring (ground straps too) is mechanically connected (crimped), electrically connected (solder), and environmentally shielded (heatshrink).

- Don't stack grounds. Between each layer you form corrosion no matter what you do, and the ground two or three places away from the block with have ~2-3 times the resistance blocking current.

- Alternator is THE power source in the system, the battery is just a reservoir. The alternator is grounded to the block. The battery is grounded to the frame which is connected to the transmission which is connected to the engine which is connected to the alternator... it's stacked grounds all over again.

- Replace anything that draws current and uses the unibody as ground path with REAL wiring, grounded to the block. Fuel pumps are perfect examples of this. Run fresh 10-14 gauge wiring for both power and ground... I've made 360whp on a stock ITR pump with 12 gauge before it started leaning, made in total 375 leaning to 13:1 AFR. I've also made 636 off a Walbro 255HP with 10 gauge wiring, but it went full rich because a hundred shot is too much to pass across a SC44 at 26 psi, meaning there was a lot more fuel (power) available there.

All in all, I'd consider cleaning the thermostat-block connection, and cleaning the thermostat housing ground. Run some welding cable from the block (as near the thermostat housing as you can) to a ground distribution point/block and run all your fancy stuff off there from battery to chassis to aftermarket electronics (widebands logged through the ECU *especially*). Keep it clean and do whatever you can to prevent corrosion.

(8:14 PM 3/23/2008) blinx9900: wow, thank you VERY much for all that info
(8:16 PM 3/23/2008) blinx9900: would you mind if i copy that info (siting your name) and start a thread on ek9.org and sticky it? a lot of the guys on ek9.org ask questions about this sort of stuff and this would be very helpful to them.
(7:46 AM 3/24/2008) Joseph Davis: Go for it!
 
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Great information! I didn't knew this! :wow: Thanks for sharing :)
 
great info, things like this often get overlooked or considered not important, when it is very important
 
just one thing, what does he mean by.... Run some welding cable from the block.....what sort of wire is he talking about here? like welding rod? or just thick power cable?
 
Welding cable - can accept lots of electrons, cable that is used in electrical welding system. Very thick and expensive.
 
Welding cable - can accept lots of electrons, cable that is used in electrical welding system. Very thick and expensive.

what like the return/earth on a mig set or something from a tig set or what?or is it a power feed wire to the trigger??
 
Welding cable - can accept lots of electrons, cable that is used in electrical welding system. Very thick and expensive.

do you have a pic :) i think were all a bit confused on this welding cable bit :shocked:
 
I will take a picture of the cable I bought. When I said very expencive I mean meter of cable can cost up to 2 EURos but meter of good welding cable can cost like 4-5 Euros. I was trying to realocate battery in trunk area. I needed very thick cable because if you want to reach block or alternator you need 4 m, and you can lost almost 1,4 V (that is what happens to me) if you use improper thin cable.
 
I will take a picture of the cable I bought. When I said very expencive I mean meter of cable can cost up to 2 EURos but meter of good welding cable can cost like 4-5 Euros. I was trying to realocate battery in trunk area. I needed very thick cable because if you want to reach block or alternator you need 4 m, and you can lost almost 1,4 V (that is what happens to me) if you use improper thin cable.

The speaker cable for my home sound sytem cost £2.20/metre LOL:D
 
DSCN6661.jpg

DSCN6660.jpg


Took these this morning at work, 25mm welding cable for mig/tig
 
Another comment, after swapping B16b into CRX body, Today I have tried to make diagnostic, and it was easy thanks to my frend Fred from Hondaphysique.com You have to ground A10 (SCS) wire (BRN color), and then I connected A18 (MIL) (probably GRN/ORN) to old crx wiring B4 connector whic leads to Check Engine light. So with grounding A10 you enable service code sequence to work, and with connectin A18 from EK9 to B4 (OBD0 CRX) you get those code sequence on check engine light.

YouTube - Type R Error Code 20

So, two long means code 20, which is Electronic Load Detector error or disconnected.

Normaly, this error shows when you have various fluctulations in current, battery close to death that wont accept voltage, alternator damaged and ELD damaged, missing some ground wires or so, BUT ALSO when you put JDM computer into USA or European vehicle, because electronic is generaly different.
Even If i move battery to trunk, and not having welding cable!
:)
 
Ok. So is there a diagram of where we should put the new earthing cables to? As he said the OEM grounds are NOT what you want to follow.....
 
my bro id relocating his battery in his car and hes using the block as a earth.
 
Can someone post pix where this thermostat block connection & ground housing located?
 
Can someone post pix where this thermostat block connection & ground housing located?

from above, look down behind your distributorm just below the level of the intake manifold is the thermostat on the corner of the block. Theres an earth with two wires crimped into it bolted on top by a 10mm bolt. :nice:
 
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