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where to mount neg bat. cable alum head hemi?

Posted By: toplescuda

where to mount neg bat. cable alum head hemi? - 07/08/11 11:58 PM

ok i asked in q n a but no responce so ask you guys
where the heck di ya mount the neg. battery cable on a hemi with alum heads?
Posted By: mickm

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 12:07 AM

same place. i have mine on the front of the head, bolt hole up top close to the valve cover.
Posted By: MR_P_BODY

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 01:00 AM

Are you running a mid plate... mount it there(out
of the way)
Posted By: toplescuda

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 02:42 AM

ok went back down and looked there is no bolt hole at all on the front of the driver head
no plates so that wont work either
didnt think alum would make a good ground???
intake,water pump and heads are alum.
Posted By: Hemi Allstate

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 03:42 AM


Aluminum is an excellent conductor of electricity. Anywhere you can to 3/8" or larger bolt should be good.
Posted By: Cab_Burge

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 03:49 AM

Due to dissimilar metals and the corrcosion that can occur in electrcical circuits do to that I would install it onto the block and not the heads Maybe ground the motor to the frame off of the bottom 7/16 bellhousing bolts, the ones on the bottom ears
Posted By: MRMOPAR622

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 03:59 AM

I ground my neg. to the frame and run a ground from each aluminum head to the side of the aluminum block then to the frame again per MSD inst..
Posted By: Dragula

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 04:48 AM

Quote:

I ground my neg. to the frame and run a ground from each aluminum head to the side of the aluminum block then to the frame again per MSD inst..




This is the only way you want to do aluminum headed engine with a nasty ignition....Each head must be grounded....Otherwise the coil wire will arc to the head or anything close to it.
Posted By: toplescuda

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 04:56 AM

i will redo it but i needed to bump motor over to do the converter bolts so right now it to the top power stearing pump bolt
Posted By: RAT PATROL

Re: where to mount neg bat. cable alum head hemi? - 07/09/11 04:31 PM

It should be grounded to the frame in the trunk, where the battery is supposed to be located.
Posted By: Hemi Allstate

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 02:52 AM

Quote:

Quote:

I ground my neg. to the frame and run a ground from each aluminum head to the side of the aluminum block then to the frame again per MSD inst..




This is the only way you want to do aluminum headed engine with a nasty ignition....Each head must be grounded....Otherwise the coil wire will arc to the head or anything close to it.





I am sure that there is a good explanation for this, but... why is this necessary with the contact of every head bolt joining the heads to the block ?
Posted By: 526ciduster

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 03:15 AM

Run ground to front and attach it to bell housing or block and to each head and intake and frame. if battery is in trunk never ground to frame in back and front too. From hours of chasing down problems this is what worked for me.
Posted By: rowin4

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 03:29 AM

Quote:

Run ground to front and attach it to bell housing or block and to each head and intake and frame. if battery is in trunk never ground to frame in back and front too. From hours of chasing down problems this is what worked for me.





I have never heard of '"not to ground back and front " Reason why? enquiring minds want to know. And for the grounding of the heads
Posted By: 526ciduster

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 03:40 AM

static loop. and also any part that shifts with heat and expansion should have a groung by itself. using a frame by itself for ground is never a good idea. I dont want to get into pee pee match but this is coming from some of the fastest in the business that have experienced the problem that high output ignitions can provide through bad grounds.
Posted By: HEMIFRED

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 04:13 AM

Quote:

Quote:

I ground my neg. to the frame and run a ground from each aluminum head to the side of the aluminum block then to the frame again per MSD inst..




This is the only way you want to do aluminum headed engine with a nasty ignition....Each head must be grounded....Otherwise the coil wire will arc to the head or anything close to it.



the primary reason both heads are grounded is for the spark plugs. Composite head gaskets can reduce the quality of their ground.
Posted By: toplescuda

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 04:51 PM

ok guys the only reason i asked is cause MY heads do not have a lug or bolt hole to mount a battery cable to
i was always under the impression that alum dont make as good of ground as steel
i had to ground it on the power steer bracket wich does not look clean to me and i want to (and will) find a differnt spot to ground it
as far as running a wire to each head??? does it not have 17bolts doing just that??
(alum head iron block)
Posted By: toplescuda

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 04:56 PM

..motor on the left

Attached picture 6723952-Photo0058.jpg
Posted By: John_Kunkel

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 05:03 PM

Quote:

I have never heard of '"not to ground back and front " Reason why? enquiring minds want to know.




Many of the wiring system suppliers (Painless, Ron Francis, etc.) recommend against using the frame as the battery ground, too many joints that might not be making good contact. They recommend running a ground cable (same gauge as the power cable) directly to the block then another from there to the body.
Posted By: toplescuda

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 05:20 PM

this is what iv been working on....angies 74challenger now with a 426 hemi
lil sollid roller (600),alum rod,landy heads
will get the tunnel ram back on it i just wanted to fire it up get timing where i wanted it then switch it over
not sure how pic will show up as did with the phone

Attached picture 6723997-Photo0028.jpg
Posted By: HEMIFRED

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 05:23 PM

to the head can also include using an intake or exhaust bolt.
Posted By: Hemi Allstate

Re: where to mount neg bat. cable alum head hemi? - 07/11/11 07:01 PM

as far as running a wire to each head??? does it not have 17bolts doing just that??
(alum head iron block)




I called MSD and asked about this. The response was that the coating on the bolts, or studs, along with the sealer, or moly lube used, can prevent a good ground!
Posted By: 526ciduster

Re: where to mount neg bat. cable alum head hemi? - 07/12/11 01:16 AM

Quote:

as far as running a wire to each head??? does it not have 17bolts doing just that??
(alum head iron block)




I called MSD and asked about this. The response was that the coating on the bolts, or studs, along with the sealer, or moly lube used, can prevent a good ground!



BINGO !!

Also there is no way that 16ft of spot welded metal is a s good as 16ft of copper wire.

my head grounds are bolted to the exhaust studs.
Posted By: Chris'sBarracuda

Re: where to mount neg bat. cable alum head hemi? - 07/12/11 01:43 AM

Quote:

ok guys the only reason i asked is cause MY heads do not have a lug or bolt hole to mount a battery cable to
I was always under the impression that alum don't make as good of ground as steel
i had to ground it on the power steer bracket wich does not look clean to me and i want to (and will) find a differnt spot to ground it
as far as running a wire to each head??? does it not have 17bolts doing just that??
(alum head iron block)





Read this..

It helped me a bunch when I re-wired my ride..


https://www.shogunindustries.com/cgi-bin...ech/ground.html

Shogun Industries

Grounding

- RESISTANCE IN ELECTRICAL GROUNDS -

There have been many discussions and some controversy about grounding methods on race cars. Much of the discussion is the questioning of, "Why isn't the chassis good enough for grounds".

Let’s begin with some basics;
On the list of good materials for electrical conductors, silver is number one and copper is number two. Due to the expense of silver, it is seldom used for electrical conductors. Copper is the most widely used and the material of choice. Actually, silver is only slightly better than copper in the amount of electrical resistance when measured, per foot of length for the same gage of wire. Without getting extremely technical, if we compare aluminum wire to copper, the aluminum has over twice the resistance of the copper. Now most racers would not even think about using aluminum wire in their race cars but consider this. Common iron has about 7 to 8 times the resistance of the copper. Then throw in the alloys such as carbon used in chrome moly and the picture gets much worse. As an example, NICHROME wire as used in heater elements, has 60% nickel, 12% chrome and 26% iron and has 66 times more resistance than copper. Most people think that metal is metal and nickel, chrome and iron all should make good conductors but you better change the way you think, because it's not all the same.

Now look at an application like a starter motor trying to crank over an engine. If the wires used to connect the starter to the battery were, 6 gage with the starter 5 feet from the battery, you would have ten feet of wire in the circuit. Five feet to the starter and five feet back to the battery. With 6 gage wire there would be about .0041 ohms of resistance in the wire, with 200 amps of current flowing, you would measure .82 volts less at the starter, than at the battery. This says that if you had 12 volts in the battery, your starter could only receive just over 11 volts. Now lets say that you used 6 gage iron wire (chassis), you would have 7 to 8 times more resistance or voltage drop and your starter would only have from 5.44 to 6.26 volts available to crank the engine. Even though you should never consider it, the use of aluminum wire would be a much better choice than iron, the aluminum wire would get 10.36 volts to the starter.

Another way to look at it is that a 6 gage wire is .184 inches in diameter and to get an equivalent iron wire, it would have to be 1.250 to 1.500 in diameter. Now I suppose if you think your frame or chassis has a cross sectional area, uninterrupted with seams or welds, equaling this dimension, you may be okay but then remember if you have alloy's such as chrome moly, your really in trouble.

The last thing to keep in mind is that as the voltage to the starter motor or any other device drops, the amount of current to operate that device increases. The increased current not only is the main drain to the battery but is also what pre-maturely burns out these items, due to over heating. The home appliance industry just loves it when your residence gets brown outs during peak electrical hours, the low voltage of a Brown-Out quickly burns up your refrigerators.




Nice Ride..


Chris..
Posted By: rowin4

Re: where to mount neg bat. cable alum head hemi? - 07/12/11 03:34 AM

I have never heard the term static loop used for the grounding on a car. I do know that running a #2 copper wire ground to the motor deffenatlly made a difference in in starting. Now should I unbolt the ground that I have to the frame in the trunk?
Posted By: moparphillie

Re: where to mount neg bat. cable alum head hemi? - 07/12/11 01:23 PM

Good morning Rowin4

When you say that adding a #2 copper wire GROUND to the engine definitely helped, where did you attach the other end of the copper ground wire? Also what condition did it help ? Were you experiencing starter heat soak or some other starting issue ?

Thanks...
Posted By: 526ciduster

Re: where to mount neg bat. cable alum head hemi? - 07/12/11 06:12 PM

Quote:

I have never heard the term static loop used for the grounding on a car. I do know that running a #2 copper wire ground to the motor deffenatlly made a difference in in starting. Now should I unbolt the ground that I have to the frame in the trunk?



if your not having problems and the car runs fine without any electrical issues leave it alone. Do you have any data logging it will show up in your logs without noticing it in the car during a run. Now if you have a wire run to front why would you need the ground at rear? Just a place to cause a problem.
Posted By: rowin4

Re: where to mount neg bat. cable alum head hemi? - 07/16/11 04:50 AM

Quote:

Good morning Rowin4

When you say that adding a #2 copper wire GROUND to the engine definitely helped, where did you attach the other end of the copper ground wire? Also what condition did it help ? Were you experiencing starter heat soak or some other starting issue ?

Thanks...





I have two batteries mounted in the trunk, both grounds are bolted to 1 stud welded to the back half frame next to the batteries. The cable going to the front is also fastened to that stud. The starter was dragging probably because of the grounding condition that I was not aware of. no other noticeable electronic/ electrical problems. The ground wire now bolts to rear intake bolt, I had it on the starter bolt but that was a pain to work with. Electrical ground for the rest of the car comes off the intake valley pan bolt to inside of the car to a terminal bar for each accessary , lights , pumps, gauges etc. And a big THANKS to Chris for the article, I'm sure it will help out many racers
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