Heddman 1-3/4" vs. Angled Plug Clearance

Mopar Exhaust Systems

  1. PurpleBeeper

    PurpleBeeper Well-Known Member

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    I believe I posted this before, but can't remember the answer. I am planning to swap motors & the new heads are Edelbrock E-streets with angled plugs (440 in 70 b-body). Each two pairs of cylinders angle in towards each other slightly.

    I would like to keep the same headers I have now (I "think" they're Heddman 1-3/4"...bought them long ago). I currently have iron heads (straight plugs) & cylinder #6's plug wire is already in there tight. As you can see, the #6 plug/wire is just left of the primary tube for cylinder #6 & the primary tube for cylinder #2 goes up/over/to the left of it. I'm afraid that if the plug is angled more towards the left (& that #2 primary tube on the left) I will have a spark plug/wire clearance issue.

    Has anyone dealt with this & what is the solution?
    I think years ago Accel had some "shorty" yellow spark plugs that might help a little, but I don't want to get the motor in before I figure this out. THANK YOU FOR YOUR HELP!

    Plug 6 Clearance PicB.jpg Plug 6 Clearance PicA.jpg
     
  2. 1967coronet440

    1967coronet440 FBBO Gold Member FBBO Gold Member

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    Hmm that’s going to be interesting, had the same Hedmans on my old 440 with 906 heads and it was tight all the way around, dented the headers up pretty good to get them on. Anyway I’m thinking maybe get a msd or similar brand cut to fit wire set with mixed boots, 90 & 45 and find the right combo.
     
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    • PurpleBeeper

      PurpleBeeper Well-Known Member

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      Funny you mention that. I've saved wire ends for years & have a mixed straight/90 set of ends on there now. "somewhere" I think I have two direct connection "any angle" ends....anybody remember those? They screw together & you can make weird angles with them. I hope I can find them since that's the best idea I have....and some shorty Accel plugs, but I'm not sure if either the "any angles" OR the short spark plugs are still made.

      It is going to be CRAZY tight for sure....hoping I don't have to buy new headers since that would wipe out any savings I had on the heads. This is supposed to be a low-budget highway cruiser motor.
       
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      • 1967coronet440

        1967coronet440 FBBO Gold Member FBBO Gold Member

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        If it helps any here’s my current 440 with victor MW heads, (sorry only pic I have right now) angled plugs, TTI headers. As you can see it’s tight even with the tti headers, I don’t see Hedmans making it any easier... Got a cut to fit msd wire set and a bunch of 90/45 ends on the shelf waiting to make my set.

        698769D7-F3B9-4C3A-8F80-179A36167E33.jpeg
         
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        • PurpleBeeper

          PurpleBeeper Well-Known Member

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          OK, crazy idea....has anyone ever had a muffler shop make ONE custom pipe? I mean, that #2 primary tube going over the top of #6 plug wire I'm concerned about has several inches of room further back towards the firewall. Is it possible (& cheap) to cut that pipe, extend the horizontal part 3", re-bend the bottom half of that pipe (where it heads towards the collector) and re-connect them?

          Is that even possible on header tubing & your basic muffler guy? I'd have one chance when this motor is pulled to get the header out easy, but it had better work or I'd be in a pickle once the new motor is installed.
           
        • 1967coronet440

          1967coronet440 FBBO Gold Member FBBO Gold Member

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          Not sure about cutting the headers but I don’t see why not... Probaly have better luck at a hot rod or even a 4x4 shop than a muffler shop
           
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          • WileERobby

            WileERobby FBBO Gold Member FBBO Gold Member

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            The accel shortly plugs are available.
             
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            • furyus

              furyus Well-Known Member

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              I have those headers on my Fury. Since the plugs point towards each other, they are angled away from the header tubes. I have MSD 45 decree wires, with the last 2 wires on the driver's side has a straight boot.
               
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              • PurpleBeeper

                PurpleBeeper Well-Known Member

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                Hey furyus, is there anyway you can post a picture of the passenger side of your motor/plug wires? I mean, on all my cylinders it does look like I will get a little more clearance with the plug wires EXCEPT for cylinder #6....the one I'm worried about. Maybe Heddman changed the design since these headers are at least 20 yrs. old.

                I think I should pull off that wire boot and look at the plug itself now that I think about it. I know that straight boot on #6 gets cooked pretty well (needs a heat sock at least)...but I haven't really looked at the plug itself lately. I have to re-set the valve last, change plugs and re-set the timing, so maybe now is the time.
                 
              • Sweet5ltr

                Sweet5ltr Well-Known Member

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                I run the shorty plugs in Eddy 84cc heads, they're expensive, but great;
                https://www.amazon.com/ACCEL-0416S-4-Shorty-Copper-Spark/dp/B007RVTBG4

                Accel also has ceramic plug boot. Heard a lot of success stories with these;
                https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=automotive&field-keywords=accel+ceramic+boot

                You could also remove your headers and mount them to your new heads outside of the car, marking where you may need to massage. No reason not to, Engine Masters proved you can nearly collapse a header and not reduce engine performance.

                 
                Last edited: Mar 22, 2018
              • furyus

                furyus Well-Known Member

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                tried to get a photo to download. no luck.
                 
              • furyus

                furyus Well-Known Member

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              • WileERobby

                WileERobby FBBO Gold Member FBBO Gold Member

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                Why go through all that fuss ? I 've used shortly plugs since forever, on mine & others cars.
                 
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                • gtxracer

                  gtxracer FBBO Gold Member FBBO Gold Member

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                  WileERobby, I too have used ACCELL shorty plugs for years. They are kinda spendy but ya gotta do whatever works. :thumbsup:
                  Bob :moparsmiley:
                   
                • not so famous bob

                  not so famous bob Well-Known Member

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                  Accel didn`t have the correct heat range available , or 3/4 reach plugs when I tried to buy a set. MSD has a set of do it urself wires that have adjustable plug ends on them, bend them the way u need. I have a set on my 440/505 w/ tti headers. Only had one boot try to start burning, wrapped the boot w/ a couple turns of header wrap.
                   
                • Sweet5ltr

                  Sweet5ltr Well-Known Member

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                  Heat range, I wonder how much that actually matters, in real world testing? Maybe they need to produce an Engine Masters episode to debunk that myth or prove it's value.
                   
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                  • not so famous bob

                    not so famous bob Well-Known Member

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                    you gotta be kidding !
                     
                  • Sweet5ltr

                    Sweet5ltr Well-Known Member

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                    :popcorn2: It would be interesting to see how much or little it makes a difference on a naturally aspirated engine, going one step colder, stock, then to one step hotter. Let's face it, most just grab whatever the parts store clerk tosses across the counter that's in-stock. I tend to stick with the slightly colder end of the spark-plug spectrum on pump gas.
                     
                  • not so famous bob

                    not so famous bob Well-Known Member

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                    I just went hotter and leaned the f.inj. out a hair more, bet it`s still rich !
                     
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