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Where to ground block?

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1Gina2G

10+ Year Contributor
810
2
May 6, 2011
Beaufort, South_Carolina
I wanted to add a new dedicated ground for both the engine block and the transmission.

I noticed the ground for the starter bolts to the transmisson bell housing, so would that ground out the transmission anyways? Or would it be best to add a dedicated ground?

As far as the engine block, does it matter where on the block you bolt the wire to?

And it's a better ground connection if you bring the wires to the battery correct? or is it better to actually go to the frame? My battery has a dedicated wire to the frame so I'm not sure.
 
I already have 2 new ground cables, would like to use them.

what do you mean by ground from block to trans? should i ground to the frame or the battery ?
 
You need one wire from the battery to the starter mount bolt, and one from the battery to the body of the car.
 
I already have 2 new ground cables, would like to use them.

what do you mean by ground from block to trans? should i ground to the frame or the battery ?

So your stock setup should already have the battery ground go to the starter mounting bolt to the battery. And then you should have another stock ground wire from intake to firewall. If your adding another ground like I said before use the engine to transmission mounting BOLT.. For the next major grounding location. Ground that wire to the body. Firewall area. Do not ground to the subframe.
 
keeping the starter ground on the trans to battery.

Adding another ground to the other trans mounting bolt to the firewall.

adding a ground to the block to the battery.

This ^^ should be good right? I don't understand what the sub frame is? Just the frame? how's the frame different then the firewall?
 
You should be fine.

The subframe is what the engine and trans bolt to. The subframe is then bolted to the main unibody. The reason you shouldn't bother grounding to the subframe is that the subframe has rubber inserts. Rubber is not a good conductor. So will not make a viable candidate for a grounding point.
 
If you negative battery post has at least two ground wires comin off it you should be good. Negative battery post ground wire should go to starter bolt. The other wire that comes off the negative battery post should go to the body. Anything else is just extra.
 
keeping the starter ground on the trans to battery.

Adding another ground to the other trans mounting bolt to the firewall.

adding a ground to the block to the battery.

This ^^ should be good right? I don't understand what the sub frame is? Just the frame? how's the frame different then the firewall?

You are really wasting your time in my opinion. The stock ground wire locations are perfectly fine. If anything just add a bigger gauge wire, but that is all that is required. There is no need for 3 grounds on the engine/transmission. There is nothing that grounds on the engine other than the alternator, starter and the ignition. All of the sensors ground thru the wiring harness.
 
The only thing I could think to recomend is a few good ground points to try if this guy bought some fancy ground wire kit that's made of special wire (like hks circle earth or something) other wise it is indeed a waste of time and effort to add a buncha crappy material wire that's not gonna cause any effect or justice at all. There is no need to mess with the factory grounds as they are plenty good right from the get go
 
There is no need of extra ground, but if you have a spare one and wanted to put them on, The only place I would recommend is the alternator.

Just add a ground from the alternator to the frame and/or to the block, that's all what will benefit, especially if you have a big amp or some sore of electronic that pulls high juice.

Note, if you have an Automatic dsm, the transmission has a ground on the end transmission cover, it attaches from the trany to the frame, this is for the automatic sensors to get a better signal, it is not required, but is good to have it so the sensors doesn't get a false signal.

I don't think you need more than what just stated.
 
So there's no dedicated engine block ground from the factory? I thought there would be.

I understand I vary well maybe adding things that aren't even needed. I just happen to have some relativeley new thick 4 guage ground wires that'd I'd like to use specifically for the purpose of thrust bearing wear protection...THEORY

It's been suggested that improper grounding of the engine block can cause wear on the thrust bearing, but I'm not hear to debate the theory, which is why I didn't even mention CW in the original post I'm just trying to do everything I can for the prevention of crankwalk and the health of the engine.

Also, there's not really any 'factory' grounds in this car, I've still yet to drive this car for the first time, and alot of electrical work has been fixed, so new grounds have been added left and right, So I'm not %100 on how things were grounded from the factory, that's why I was just trying to clarify the best way to ground the engine and or transmission.


Since you are talking about grounds, don't forget the throttle body ground strap for the idle switch.

I totally didn't realize that the TB has it's own ground strap? :confused:
My TB is new & rebuilt, where/what would I look for?
 
Last edited by a moderator:
I would also recommend a ground from the alternator case to the unibody/frame.

If you have that much extra 4ga laying around then you could rewire the positive from the alternator to the battery to combat possible voltage drop at high rpms.

I added a few extra grounds myself, and it was probably overkill.
 
I would also recommend a ground from the alternator case to the unibody/frame.

If you have that much extra 4ga laying around then you could rewire the positive from the alternator to the battery to combat possible voltage drop at high rpms.

I added a few extra grounds myself, and it was probably overkill.

I deffinatley wouldn't mind doing that, anything to help the cars reliability, and run correctly :thumb: Already did the fuel pump rewire 'fix'
My dad's an electrician, so I DO have the extra wires I can use for whatever I need to do.

Any links on this? Would you happen to know where the ground strap for the TB mentioned above is?
 
Thrust bearing wear? Crank walk? And your insurance policy aginst this is a ground wire on the block? No way is a piece of 4awg wire gonna save you from thrust bearing issues. Crank walk is never gonna happen because there isn't a engine ground wire. That's a issue more towards starting the car up with a super duper heavy aftermarket clutch. If you had a super strong after market pressure plate and when you hold the clutch pedal down to start the car there's a whole awfull amount of squish load pressed on the crank from the clutch pushin hard at the flywheel then start it up for a split second with not much oil pressure yet and do that about 50,000 times and now you MAYBE MIGHT have thrust bearing wear.


A extra ground most certainly will not fight off crankwalk. Only reason for beefier ground system is if your running a lot of aftermarket electricall stuff. Don't over think it man. Your factory ground is plenty good. And if your just lookin to burn up that nice 4awg wire than use it like this

Replace the two factory ground wires with your nice stuff. Now for the extra. Ground alt to body, ground coilpack to body, ground ignitor to body, run a additionall jumper ground from the body back to your negative battery post
 
http://www.dsmtuners.com/forums/articles-engine-fuel/342560-crankwalk-depth-explanation.html

This is what I read. Never said this was my full-proof plan to feel crankwalk proof. As anybody that's read about CW knows, the real cause is unknown, most likely not just 1 thing but multiple things, and there's a few small things you can do to help the thrust bearing out.

As I was saying in my original post, I just wanted to figure out if it mattered where on the block would be best. I'll just take a guess. And still didnt know if the battery post was a 'stronger' ground since it's more direct, where as grounding to the frame would have some resistance. Doesn't matter I guess, and it's probably also better do have grounds isolated rather than piled up in one place..

This is from the link above:
"Electrical Grounds
Yep. I bet most of you didn't think electrical grounds for the engine were that important, right? Well it has been shown that poor engine grounding can actually cause a thrust bearing to prematurely fail. If there is too much current in the vehicles drive train, it must be corrected. In order to find this out get a digital volt meter. Disable the vehicle from actually starting, but will still be able to crank the starter. Ground the meter to the vehicles battery. Place the positive on the transmission. Have the starter cranking for at least 4 seconds. There should be no more than .01 volts. If the meter exceeds .01 volts, add or replace engine ground straps. (From the frame of the vehicle to the engine). It would also be a good idea to ground the transmission to the frame. Better grounding can also aid in better performance"
 
I totally didn't realize that the TB has it's own ground strap? :confused:
My TB is new & rebuilt, where/what would I look for?

It's a small piece of metal shaped something like an "L", that goes over the upper right (front) intake manifold to TB stud, and screws into the top of the TB with a phillips screw.

Sorry... don't have a pic handy at the moment.
 
Uh,... Your rated as a WISEMAN and your not gonna chime in about crank walk? OP there is no way in hell that info you posted is ever gonna shake down like that. I've been in the dsm world for 11 years, I've owned 3 first gens and 3 second gens all of which have been the four wheel drive turbo model. Yes I've read about every piece of info on crank walk that there is to offer. Thrust bearing faliur is caused by heavy clutches that put a tremendous amount of "squish" on the crank when you hold the clutch pedal down and start it. Add the fact that all the engine oil has drained back to pan and that start up (even worse when engine is all the way cold) doesn't fling oil all the way super fast when the engine is cranking. Add these two together and thrust bearing wear may happen

Why do you think people disconect the neutral safety wire off the clutch pedal? That's to start the car with no clutch pressin super hard on the flywheel which then pushes super hard aginst the crank. That side load started up with out $hit for oil for that tiny second about 50,000 times may cause bearing wear.

The mystery reasons that you have read about were why the hell this could happen to a stock set up. As in no heavy clutch and it still happens. Not to mention over half of the info you have read is over ten years old... The brainiacs on this sight have long figured out the explination for crank walk

Trust me man a ground wire on your engine isn't gonna have any effect on that. I could post reason after reason as to why that has nothing to do with crank walk but because my reputation status doesn't have stars next to it what the hell would I know right?

Ill wait for someone with all the lil stars next to there avatar to come along and back me on this. The only gain to be made from extra ground is reduced audio noise, brighter lights, and a more constant voltage. THATS IT

And maybe if you drop the coin on a real ground wire kit like from sun auto or hks or somethin than you MAYBE MIGHT dyno like 1hp higher. Maybe
 
http://www.dsmtuners.com/forums/articles-engine-fuel/342560-crankwalk-depth-explanation.html

This is what I read. Never said this was my full-proof plan to feel crankwalk proof. As anybody that's read about CW knows, the real cause is unknown, most likely not just 1 thing but multiple things, and there's a few small things you can do to help the thrust bearing out.

As I was saying in my original post, I just wanted to figure out if it mattered where on the block would be best. I'll just take a guess. And still didnt know if the battery post was a 'stronger' ground since it's more direct, where as grounding to the frame would have some resistance. Doesn't matter I guess, and it's probably also better do have grounds isolated rather than piled up in one place..

This is from the link above:
"Electrical Grounds
Yep. I bet most of you didn't think electrical grounds for the engine were that important, right? Well it has been shown that poor engine grounding can actually cause a thrust bearing to prematurely fail. If there is too much current in the vehicles drive train, it must be corrected. In order to find this out get a digital volt meter. Disable the vehicle from actually starting, but will still be able to crank the starter. Ground the meter to the vehicles battery. Place the positive on the transmission. Have the starter cranking for at least 4 seconds. There should be no more than .01 volts. If the meter exceeds .01 volts, add or replace engine ground straps. (From the frame of the vehicle to the engine). It would also be a good idea to ground the transmission to the frame. Better grounding can also aid in better performance"

We are not blaming you about the false information, we just giving you the right information so you know how things works.

That article has some true information but not a lot, but it doesn has quite a bit of wrong information, do a google search about crank walk and you will find a lot of good information for you to get a really good knowledge ( I am not saying you haven't search).

On a side, to explain a little about,,,, block grounding.
The block, Transmission and Starter gets grounded by the cable that comes from the battery, the cable has to be bolted down to the bolt that holds the Starter, this way the starter will have a strong ground by the bolt, the transmission will get grounded by the bolt head and cable which the cable will be touching the transmission housing, the Block will get grounded by the transmission housing and the starter plate,.

There is a light wire from the back of the Intake to the firewall, this is for the TPS, if you don't have that wire, then you need to put one, or add a ground to the Throttle body, You don't need a ground for the throttle body if you have the ground on the intake manifold, some people have had problems not getting ground on the throttle body even with the ground wire at the intake manifold, this is because the bolts from the throttle body are not clean enough for the ground to pass and make contact to the throttle body, There is another wire at the end cover of the transmission (Automatics only), this is for the sensors of the transmission, All the other sensors will get its own ground by the wiring harness which they are attached to the firewall.
Some people have being saying that have found a ground wire (from factory) from the alternator to the block, personally, I haven't seen any car with it, and most of the cars doesn't have it and performs very well with out it.

Hope this clears a little about Block Grounding.
 
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