ECU Ground location with a FFIM

[arknotts]

I currently have a FFIM, and during the install I just temporarily grounded the ECU wires to the chassis. They are grounded to the back of the intake manifold stock. I have no location on my new one to ground them, except for maybe on one of the studs holding it to the head (I would have to grind off some of the coating though).

I figured there was a reason Toyota grounded it to the intake manifold to begin with. As a matter of fact, I was doing a bit of googling and have found that a lot of cars ground the ECU to the intake manifold. Anyone know the reason for this? It seems as though it wouldn't be as good of a ground source as the block.

Can I just bolt this to the block? I'm being a little picky about this since these are ECU grounds, and I really don't want flaky grounds here affecting my tune at higher boost levels.

 

[SC61 MK3]

As far as I know a good ground is a good ground and all good grounds in the car should be connected together through the chassis, this is coming from a car audio guy

 

[spikesnstuff0905]

The block is the center of your entire grounding system. Most people think it's the chassis, but it isn't. Everything gets back to your block eventually, and ideally everything would be grounded straight to it.
I don't think you'll see problems with grounding to the frame, but over the years the welds between panels start to rust, adhesive fails, corrosion builds up between parts, and this all creates resistance the electricity has to pass to get back to the block.

 

[jetjock]

^ Say what?

 

[arknotts]

As far as I know a good ground is a good ground and all good grounds in the car should be connected together through the chassis, this is coming from a car audio guy

Not all grounds are the same, and I'm sure there are points on the chassis that are not the greatest to ground to. As far as having the most direct path to the battery, the block would be better since it is directly grounded to the negative terminal and is solid iron. Although I'm no expert on the subject, improperly grounded components can cause a ground loop which can introduce noise into the system...i.e. not all "good grounds" are optimal.

The block is the center of your entire grounding system. Most people think it's the chassis, but it isn't. Everything gets back to your block eventually, and ideally everything would be grounded straight to it.
I don't think you'll see problems with grounding to the frame, but over the years the welds between panels start to rust, adhesive fails, corrosion builds up between parts, and this all creates resistance the electricity has to pass to get back to the block.

Wouldn't the "center" (or rather destination) of the grounding system be the negative battery terminal?

 

[SideWinderGX]

There is no central ground point (block or chassis). As long as the ground is connected to a physically large piece of conductive material it is fine, it doesn't matter where it is (within reason...no lugnuts there, wiseguys).

 

[spikesnstuff0905]

http://www.ek9.org/forum/other-technical/3480-helpful-information-grounds-very-important.html
Yes, i understand it's from a Honda forum.
No, i don't think that makes the information any less useful.

 

[whitemike]

i don't think that makes the information any less useful.

Except that you're wrong about the info you posted?

 

[spikesnstuff0905]

How so?

 

[hvyman]

There is no voltage nor amps in a ground so how can something that is not there get pushed to something else?

Amps push volts through resistance.

 

[spikesnstuff0905]

I don't know, since grounds have no driving force behind them anyways what is the point of grounding them to anything? It's not like they are getting pushed into the ground wiring, so how does the current pass through the wire onto your ground location?

---------- Post added at 04:59 AM ---------- Previous post was at 04:58 AM ----------

What is the recommended ground layout if you were to, say... relocate your battery to the hatch?

 

[Devin LeBlanc]

This is not A/C its D/C

 

[spikesnstuff0905]

Regardless, you need to complete the curcuit, right? What does this have to do with anything? I feel like i bought a puzzle and put the entire thing together well enough to get what it's supposed to be, but there are a few pieces missing in the box. SOMEONE GIVE ME MY PIECES!

 

[hvyman]

You were wrong and posted false facts in the tech section and are now demanding. Not really the way to go about things.

Did you realize that when you have 12v before the bulb an 0v after that all the power is used in the part that it is supplying? You should read up on electrical and stop being an asshat.

 

[spikesnstuff0905]

This still doesn't relate to my original post at all. The chassis is a terrible electrical conductor, the block is the central ground for the motor. No, the battery isn't the end ground, because it is only a recepticle for energy created by the Alternator. The battery is not the originator of your motors electrical current, and in fact is only there to start the car. the Alternator is the power source, and that is why it's grounded to the motor, not the chassis or the battery. What you're saying is that everything in the car uses every scrap of power supplied to it, and therefore does not need a ground because once the component is done with the charge there is nothing left? It seems like ever since the other day when you started being a fuckmouth in that other thread you make a point to post something negative and degrading about whatever I say instead of just answering the OP's original question (which should be easy for you with your infinite and indefinite knowledge of every-fucking-thing). Being condescending to people because they ask for the answers that you apparently have is not the way to go about things, since Supramania is now about giving each other etiquette lessons. You should go read up on human interaction and stop demanding respect, when you have done nothing to show me personally that you've earned it. Asshat.

 

[hvyman]

To op steel and iron are better grounds. The steel bolt helps with the grounding in the orig setup. I would bolt to block or frame rail which ever is easier.


I Do not demand respect. I dont care what people think an i also dont tell random people that im going to kill them over there misfortune. You really Shouldnt curse as much either. 1 your mad obviously. 2 Out of respect to other members that view sm in there work place. Demanding anything on here will not get you any where. I could say search which you should but im not.

Here are the ground points
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=151

Most of them are on the chassis.

Yes a component uses up its power. Its basic electrical. If the power was not used up then the alt would not need to be constantly charging.

Maybe you should take an electrical class.

Edit i was also a little drunk the other night waiting to get sushi. Ive been trying to stop drunk posting. Apologies.

 

[spikesnstuff0905]

I haven't asked for aanything but for you two to explain why i was wrong. If you explain to me that i made a mistake, most of the time i will thank you for correcting me, and add it to what i know. If you tell me i'm wrong and don't explain, don't expect me to take you seriously. If you can't even explain your logic to someone clearly enough for it to be useful, why even say anything in the first place?

Just because the original grounds are on the chassis does not mean the best ground is the chassis. I think we all know by now that manufacturer specs. are not always correct... Look at most old hondas. there are three ground wires. 12ga each. they're meant to support like 100hp for 15 years and thats it. You think people are doing 300hp swaps with the oem grounds? No.

My point is I'm NOT an electrician, and as i said, if there is no waste, then why does anything in the car need a ground? Whether the component needs to dispell electricity, or a lack there of, it still needs to get rid of something, or there would only be need for a supply wire. To complete a curcuit you need a ground, and a 20yr old chassis is not the most reliable one.

I'm poor.

Accepted.

 

[Zumtizzle]

^Relax Man!

 

[jetjock]

Lmao. You guys are killin' me. Hey Jon, are you getting all this down?

 

[arknotts]

LOL...geez guys . A lot happened overnight! I've not been able to draw much of a conclusion, so I think I'm just going to ground it to the block unless someone with more knowledge than me chimes in. If I can't find a good spot there it will go on the frame rail that my block is grounded to.

Lmao. You guys are killin' me. Hey Jon, are you getting all this down?

JJ, I know you're the electrical guru around here. Any advice? Or am I just thinking too hard again?