Cylinder head ground straps

Discussion in 'PSI Superchargers Tech Questions' started by BrianD, Sep 29, 2012.

  1. BrianD

    BrianD Member

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    What are everyone's thoughts on grounding the heads to the block/mag with dedicated ground straps? It seams as if this would be a good idea? With all of the effort being put into making the front end of the ignition systems as efficient posable, it seems as if it be a simple way to make the completion of the circuit efficient as well.
     
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  2. srxspec

    srxspec Member

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    I run a ground wire from the head to the block, distributor to block, and then from the block to the chassis as well. I don't know if it makes a big difference, but it definitely doesn't hurt.
     
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  3. TAF 316

    TAF 316 Member

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    run a current TF car dual 44s....dont use um at all anymore
     
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    Last edited: Sep 30, 2012
  4. lucky devil

    lucky devil Member

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    When we started using a 44mag , we would get cylinders dropping under load , the plugs were cracking on random cylinders. The cure was to add more earth straps.

    We run them from one cylinder head to another , front and back , and from the heads down to the frame. It cured our problem
     
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  5. moparchris440

    moparchris440 Member

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    its a must!!
     
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  6. Blown5402

    Blown5402 Member

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    MSD says to ground the heads

    MSD says it makes a better electrical path to the sparkplugs to ground the heads, and we do and have never had any problems the last 10 to 12 years! THANKS! Jim
     
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  7. Kramer Metal Fab Inc.

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    Ground straps

    What type/gage of wire/cable are you guys using? Battery Type wire and ring terminals?
     
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  8. Wildcatracing

    Wildcatracing Member

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    earth straps

    the best kind is the older style flat rectangular nickel coated copper and you only need 3/8" lugs on each end. At the end of the day almost anything is better than nothing and if nothing else it eliminates a potential issue
     
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  9. Iron Mike

    Iron Mike New Member

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    I know it is a "must" but why?
    really why

    ally heads, copper head gaskets, iron block all held together with about 25studs.

    some of the best electrical conductor and we join them with a relatively small earth strap and it is all so much better.

    Tyson (Electrical Engineer)
     
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  10. aj481x

    aj481x Member

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    We have always used them because of MSD info, but it is interesting that the nitro cars, with twice the amperage don't seem to have any.
     
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  11. Wildcatracing

    Wildcatracing Member

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    earth straps

    its because of the different types of materials and the fact that they are not 'bonded' as such just bolted together. The different materials can set up electrolysis which results in high resistance. It may be better to suggest this is a preventative action rather than corrective. It also eliminates this as a potential cause of problems
     
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  12. smashm

    smashm Member

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    we made one harness with 10 gauge wire & soldered d-rings.runs from cyl head to cyl head to coil ground.also have main ground from battery lug at fr of car to coil ground.no problems so far.
     
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  13. Cisco AA/FA

    Cisco AA/FA Member

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    Where on the heads do hou drill, and how deep do you drill?
     
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  14. smashm

    smashm Member

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    our veney heads already had the holes when we bought the motor.we use a 1/4 20 bolt,1/4 inch long w a little blue loctite for good measure. also,the holes are right up front on the face of the heads.
     
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  15. badbird

    badbird New Member

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    never had a problem with putting them on exhaust studs just to the chassis
    iv often wondered ok so the heads only bolted but you just bolt the earth straps on so whats the difference, we do this cause everyone else does it, ;)
     
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  16. Mike Canter

    Mike Canter Top Dragster
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    It is a requirement to ground the heads to each other and then both to the same ground lug as the coil is grounded to. You don't need but a 10 or 12 gauge wire. Grounding the heads to the block is not a requiremnt but doesn't hurt but is not a good path for current return. I have seen EGTs on one head fall because the plugs are not firing at full potential because of a bad ground path back to the coil. Current has to have a complete good path and that for our motors is out of the high voltage windings of the coil through the rotor and cap, through the ignition wires to the plug and across the center electrode to the ground strap and from the ground strap of the plug back to the ground lug the coil uses. If that current path is weak or broken the the spark power at the plug will be weak or non existent. It is amazing that the heads will not be grounded through the studs and head gaskets to the block but they will not. You can actually see spark etching on the face of the heads and copper head gaskets if the ground (earth for some) wires are not installed. Without them you may think you are getting full spark potential but odds are you are not. Why spend all that money on a mag system and risk not completing that current path.
     
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    Last edited: Oct 11, 2012

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