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  •  » Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

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    7/02/2021 5:38 PM  #1

    josh-kebob
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    From: Madison, AL
    Registered: 4/06/2013
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    Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Here on Mustang Myth Busters, Season one, Episode one, we address the age old debate, "HiPo manifolds on GT40P heads cause interference with spark plug removal/installation."

    To test that theory, we employ semi-scientific principles using a set of new HiPo mannys (thanks TimC) on the Mustang Myth Busters 2000 Explorer 5.0/GT40P heads,  test mule engine.

    Carefully aligning each manifold, our myth buster technician, Kari Byron, (I wish she was here) expertly installed all manifold bolts, torquing each bolt to manufactures specifications.

    Next, using a perfectly calibrated 5/8 spark plug socket and starting at cylinder #1,  we expertly inserted the socket onto the spark plug, noting with interest, we experienced zero interference from the HiPo manifold. Surprised by our initial findings but not deterred, we continued the process in precisely the same manner on the remaining seven spark plugs, all with the same results.

    Our findings therefore conclude that there was/is zero interfence with the HiPo manifolds on GT40P heads with respect to accessing each spark plug for the purpose installation or removal.

    Our conclusion?

    This Myth is BUSTED!!
    (Billy Walton didn't type that last word.)


    Now to be serious. I have a 5.0 P-head engine on a stand and after acquiring a new set of HiPo manifolds, I wanted to test fit them and check to see if I'd experience any clearance issues accessing the spark plugs...I did not. Others have stated these manifolds on P-heads are problematic with respect to spark plug access.

    All I can say is, if you use these manifolds on these heads vs using headache prone headers, you'll be just fine.

    Stay tuned for the next episode of Mustang Myth Busters....

    Last edited by josh-kebob (7/02/2021 7:39 PM)

     

    7/02/2021 5:45 PM  #2

    Chaplin
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Pics or it didn't happen!!  😂

     

    7/02/2021 7:26 PM  #3

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Chaplin wrote:

    Pics or it didn't happen!!  😂

     
    Sure thing....I will post multiple pics on VMF, its really easy to do, and you can see for yourself this myth buster episode....

    Last edited by josh-kebob (7/02/2021 7:27 PM)

       •Thread Starter
     

    7/02/2021 7:29 PM  #4

    Chaplin
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Perfect. 😀

     

    7/02/2021 7:41 PM  #5

    cman66
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    From: Ponchatoula, LA
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Thanks Josh for the info.
    Donor for ol Paint is 2000 Exxploder with 5.0 GT40 p heads'
    Will have to source Hi Po Manifolds.
    Don't need anymore headaches than I am making for myself.
    Cman

    PM me your username on VMF I'll look for pics.

     

    7/02/2021 9:07 PM  #6

    6sally6
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    From: Surfside Beach,SC
    Registered: 4/02/2013
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    I guess we (I also) are guilty of posting stuff "we read/heard" as gospel even though we have not first hand knowledge.
    Maybe we think we are hep'in somebody prevent a problem or........ whateverrrrrr. 
    Does that qualify as a lie??? (well it ain't the truth so you finger-it-out!!)
    A feeble attempt to help and a Mustang urban legend is born!!!!!!
    OK.....how bout a group "I'm sooooorrrrry"!
    6sally6

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    7/03/2021 5:53 AM  #7

    Bullet Bob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Well...the ones you got from my Falcon Friend DEFINITELY had spark plug interference.  So I can only surmise that the ones you tested for this episode of MMB are slightly different.  Either the same mfg. made a change or they are from a different mfg.
    Whatever the reason, you might want to post the source, manufacturer, and exact part number.  I can't recall where we got the ones for the Falcon...NPD I think...butt (TS&T) maybe not.
    Thanks for that good info, Josh.  Having run HiPOs on the Heap for over 30K miles I absolutely believe they are a far better (simpler) solution than ANY headers on a street driver.

    BB1
     

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
     

    7/03/2021 5:57 AM  #8

    TKOPerformance
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    There's a second part to this though, how did the plug wires fit and what boots are needed? 

    Common knowledge is always common, but often not as it turns out knowledge. 

     

    7/03/2021 6:04 AM  #9

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Bullet Bob wrote:

    Well...the ones you got from my Falcon Friend DEFINITELY had spark plug interference.  So I can only surmise that the ones you tested for this episode of MMB are slightly different.  Either the same mfg. made a change or they are from a different mfg.
    Whatever the reason, you might want to post the source, manufacturer, and exact part number.  I can't recall where we got the ones for the Falcon...NPD I think...butt (TS&T) maybe not.
    Thanks for that good info, Josh.  Having run HiPOs on the Heap for over 30K miles I absolutely believe they are a far better (simpler) solution than ANY headers on a street driver.

    BB1
     

    Bob, on the mannys I got from your friend, definitely were ground on the outside so as to afford more falcon shock tower clearance but, I couldn't see where the area around the spark plugs had been ground....could be wrong tho..

       •Thread Starter
     

    7/03/2021 8:02 AM  #10

    Bullet Bob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    josh-kebob wrote:

    Bullet Bob wrote:

    Well...the ones you got from my Falcon Friend DEFINITELY had spark plug interference.  So I can only surmise that the ones you tested for this episode of MMB are slightly different.  Either the same mfg. made a change or they are from a different mfg.
    Whatever the reason, you might want to post the source, manufacturer, and exact part number.  I can't recall where we got the ones for the Falcon...NPD I think...butt (TS&T) maybe not.
    Thanks for that good info, Josh.  Having run HiPOs on the Heap for over 30K miles I absolutely believe they are a far better (simpler) solution than ANY headers on a street driver.

    BB1
     

    Bob, on the mannys I got from your friend, definitely were ground on the outside so as to afford more falcon shock tower clearance but, I couldn't see where the area around the spark plugs had been ground....could be wrong tho..

    Hmmmm? No, you could be right, probably are.  Old minds......
    Good info, Josh.

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
     

    7/03/2021 9:42 AM  #11

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    TKOPerformance wrote:

    There's a second part to this though, how did the plug wires fit and what boots are needed? 

    Common knowledge is always common, but often not as it turns out knowledge. 

    Ford performance, 9mm wire set, 135° boots.....they're BLUE....

       •Thread Starter
     

    7/03/2021 12:03 PM  #12

    MS
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    From: Canyon Lake, Texas
    Registered: 1/24/2013
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Thanks, Josh!

    I just bought a set of hipo manifolds yesterday after shopping around at as many vendors I could think of. Best price was Kentucky Mustang, then they added a 5% discount too!  Fourth of July discount…
    Don’t forget to order the correct bolts to go with the manifolds.

    I bought the manifolds because everybody seems to be out of them and the prices are getting higher weekly.  I want a set on the shelf for future use.

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

    7/03/2021 1:53 PM  #13

    6sally6
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Always ran the "FoMoCo" 135* wires on my stuff and...........was never 'really' happy with how close they came to my heads and stuff.
    My buddy Pat gave me some 90* Shivel-lay wires (yellow onez) to try and........great fit! 
    NONE were close to the headers/heads anything that could get melted.
    I'm ordering  Ford Blue wires that fit a 350 Shivel-lay next time. (right now I have 4 blue and 4 yellow warz...
    'looks-real-nice-Clark'!
    6sal6

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    7/03/2021 2:36 PM  #14

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    6sally6 wrote:

    Always ran the "FoMoCo" 135* wires on my stuff and...........was never 'really' happy with how close they came to my heads and stuff.
    My buddy Pat gave me some 90* Shivel-lay wires (yellow onez) to try and........great fit! 
    NONE were close to the headers/heads anything that could get melted.
    I'm ordering  Ford Blue wires that fit a 350 Shivel-lay next time. (right now I have 4 blue and 4 yellow warz...
    'looks-real-nice-Clark'!
    6sal6

    Get rid of the headers and you'll have no issues with plug wires...

       •Thread Starter
     

    7/03/2021 2:39 PM  #15

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    MS wrote:

    Thanks, Josh!

    I just bought a set of hipo manifolds yesterday after shopping around at as many vendors I could think of. Best price was Kentucky Mustang, then they added a 5% discount too!  Fourth of July discount…
    Don’t forget to order the correct bolts to go with the manifolds.

    I bought the manifolds because everybody seems to be out of them and the prices are getting higher weekly.  I want a set on the shelf for future use.

    Nice to know. I really like dealing with KY Mustang too.

       •Thread Starter
     

    7/03/2021 8:07 PM  #16

    MS
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    From: Canyon Lake, Texas
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    About those 90 degree wires.  With GT40p heads they route the wires directly against the header flanges. I know because I have a set on my truck engine. The 135 degree wires are the only way to go for proper routing.  I have them on my stroker 427 and on every other small block I have ever built with no problems, headers or not.

    I cannot imagine how 90 degree boots would ever fit correctly, but if they work for you, who can argue with that!

    Kind of like installing a radiator in FRONT of the core support. To each, their own!

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

    7/04/2021 1:54 AM  #17

    KM
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    Registered: 4/01/2013
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Good information, I running with the P heads on my 351w and using JBA shorty headers , attempted to use the hippo manifolds but they will not work on a 1971 mustang due to the steering gear box. Also using plug wires with ceramic boots. 

    If its worth doing do it right !
     

    7/04/2021 9:16 AM  #18

    Nos681
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    From: Atlantic Mine, Michigan
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Will ceramic ends clear the Hipo’s or the Jba’s?
    Are ceramic ends straight, 135, 90 degrees?
    Regardless of steering box.

    Just trying to understand clearance problems.
    Thanks

     

    7/04/2021 12:04 PM  #19

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Send me a set of ceramic end wires and I'll test them for you....free!

    Last edited by josh-kebob (7/04/2021 3:36 PM)

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    12/09/2021 8:57 PM  #20

    BILLY WALTON from GEORGIA
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    josh-kebob wrote:

    Send me a set of ceramic end wires and I'll test them for you....free!

    You dont have a extra set or know of a set of GT40P heads do you? I am getting stuff up for when I snatch the stock 289 out of my 65.
     

    Its really me....I fixed my caps lock .
     

    12/09/2021 11:51 PM  #21

    josh-kebob
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    No. If I run across some I'll let you know

       •Thread Starter
     

    12/10/2021 10:58 AM  #22

    Steve69
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    Nos681 wrote:

    Will ceramic ends clear the Hipo’s or the Jba’s?
    Are ceramic ends straight, 135, 90 degrees?
    Regardless of steering box.

    Just trying to understand clearance problems.
    Thanks

    I have a set of JBA's I bought last year that I was going to install on my 69.  After doing some measuring it looks like on the drivers side it might hit the shock tower.  Looks like they will hit my power steering hoses also.  So Im debating on Hipo's too.  
     

     

    12/10/2021 10:38 PM  #23

    BILLY WALTON from GEORGIA
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    josh-kebob wrote:

    No. If I run across some I'll let you know

    Thanks

    Its really me....I fixed my caps lock .
     

    9/21/2022 9:20 PM  #24

    BILLY WALTON from GEORGIA
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    From: CARROLLTON GEORGIA
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    https://www.ebay.com/itm/202948005633

    I got these wires to use on my 5.0 build that has the GT40p heads and Hi-Po manifolds are these 45/135 ends gonna work the best or do I need the 90 degree like some have mentioned?
    I can buy some ends I have not cut them yet.
    Is anybody running the GT40p heads with Hi-Po manifolds?

    Last edited by BILLY WALTON from GEORGIA (9/21/2022 9:23 PM)

    Its really me....I fixed my caps lock .
     

    9/21/2022 9:25 PM  #25

    BILLY WALTON from GEORGIA
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    Re: Mustang Myth Busters: Spark Plug Clearance; Hipo mannys on GT40P heads

    MS wrote:

    About those 90 degree wires. With GT40p heads they route the wires directly against the header flanges. I know because I have a set on my truck engine. The 135 degree wires are the only way to go for proper routing. I have them on my stroker 427 and on every other small block I have ever built with no problems, headers or not.

    I cannot imagine how 90 degree boots would ever fit correctly, but if they work for you, who can argue with that!

    Kind of like installing a radiator in FRONT of the core support. To each, their own!

    so no problems with the 135?
     

    Its really me....I fixed my caps lock .
     

     

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