What? 'Nother 360 magnum on the dyno?

Magnum Engine Swaps

  1. IQ52

    IQ52 Well-Known Member

    Messages:
    2,267
    Likes Received:
    1462
    Joined:
    Jul 30, 2011
    Location:
    Idaho
    Local Time:
    10:50 PM
    Tried to build a 360 horsepower 360 for a '96 2whl drive pickup. We haven't yet set the dyno up to run the stock/modified computer, so just to break the 360 in we used a modified/stock '74 distributor and the 850 cfm Mighty Demon (yeah, I know) we had laying around.

    Hughes/Edelbrock FI Air Gap intake manifold
    Stock rockers
    Stock lifters
    Comp XR265HR-14 Roller
    Mildly ported stock Magnum heads 255 cfm @ .500"
    forged pistons 9.3:1 compression

    After break in and a coupla' pulls,

    RPM..........TQ/HP

    2500........350/166
    2600........354/175
    2700........351/180
    2800........352/188
    2900........362/200
    3000........380/217
    3100........390/230
    3200........394/240
    3300........400/251
    3400........407/264
    3500........414/276
    3600........417/286
    3700........421/297
    3800........422/305
    3900........427/317
    4000........431/328
    4100........431/336
    4200........436/348
    4300........433/355
    4400........430/360

    Well, we made it! Might as well wind it a few more RPM.

    4500........427/366
    4600........423/371
    4700........424/379
    4800........419/382
    4900........408/381
    5000........407/387
    5100........400/388
    5200........392/388
    5300........389/392
    5400........378/389
    5500........377/394

    The owner will be here tomorrow to see it run. He said, "Does it have a nice lope?"

    Ah, nope, it's got a real mellow idle. It's meek, that is, strength under control!

    What is it with the lopey crap? If you don't need the lope, why bother? You think it makes you look tough? Buncha cars lope that can't spin the tires. How cool is that? It's like buying yourself a trophy to put on the mantle.

    We're gonna hafta put a raunchy exhaust on it for him. Make it sound like it lopes.
     
    • Like Like x 3
    • Abodybomber

      Abodybomber Breaking street machines , since 1983.....:) Legendary Member

      Messages:
      31,731
      Likes Received:
      10443
      Joined:
      May 21, 2011
      Location:
      Arroyo grande ca
      Local Time:
      9:50 PM
      LMAO! NICE TORQUE CURVE! Next question: 1.92,1.97,or 2.02 intake valve?. Guessing, 2.02 GREAT POST!
       
    • ir3333

      ir3333 Well-Known Member

      Messages:
      4,051
      Likes Received:
      713
      Joined:
      Jun 1, 2008
      Location:
      ontario,canada
      Local Time:
      11:50 PM
      that lope helps at the big end,but if you're not careful very disappointing at
      lower rpm on the street
       
    • IQ52

      IQ52 Well-Known Member

      Messages:
      2,267
      Likes Received:
      1462
      Joined:
      Jul 30, 2011
      Location:
      Idaho
      Local Time:
      10:50 PM
      You guessed correctly on the valve size.
       
      • Like Like x 1
      • JGC403

        JGC403 Well-Known Member

        Messages:
        972
        Likes Received:
        34
        Joined:
        Nov 22, 2010
        Location:
        Baileyton, TN
        Local Time:
        10:50 PM
        Some people just like the sound at idle. I would rather have performance than sound.
         
      • oldkimmer

        oldkimmer FABO Gold Member FABO Gold Member

        Messages:
        10,453
        Likes Received:
        1296
        Joined:
        Nov 11, 2006
        Location:
        Kindersley, Saskatchewan,
        Local Time:
        11:50 PM
        ....................Sweet........I like a lil chop............kim.......
         
      • Abodybomber

        Abodybomber Breaking street machines , since 1983.....:) Legendary Member

        Messages:
        31,731
        Likes Received:
        10443
        Joined:
        May 21, 2011
        Location:
        Arroyo grande ca
        Local Time:
        9:50 PM
        Thanks. Conservative cam timing,well done heads usually destroy the rest. Damn nice build.
         
      • PanGasket

        PanGasket has cork sides

        Messages:
        4,625
        Likes Received:
        64
        Joined:
        Mar 16, 2010
        Location:
        Gainesville, GA
        Local Time:
        12:50 AM
        Wow! Look at that torque! very well done :cheers: That thing will definitely pull some cargo.

        Sorry for such a novice question, but why does it suddenly drop almost 100ft/lbs at 3200?
         
      • Abodybomber

        Abodybomber Breaking street machines , since 1983.....:) Legendary Member

        Messages:
        31,731
        Likes Received:
        10443
        Joined:
        May 21, 2011
        Location:
        Arroyo grande ca
        Local Time:
        9:50 PM
        Pure bitchin! Everyone about the peak numberib the day. I was taught, velocity and balance. I think you found balance.(and then some).
         
      • IQ52

        IQ52 Well-Known Member

        Messages:
        2,267
        Likes Received:
        1462
        Joined:
        Jul 30, 2011
        Location:
        Idaho
        Local Time:
        10:50 PM
        Sucked a small humming bird into the intake right at that point,





        or crappy proof reading..........
         
        • Like Like x 1
        • OldmanRick

          OldmanRick Well-Known Member

          Messages:
          7,112
          Likes Received:
          320
          Joined:
          May 11, 2012
          Location:
          Ladson, Sc
          Local Time:
          12:50 AM
          394lbs......it's a misprint.

          Nice work Jim :thumbrig:.

          I assume in the final configuration that there may be a modest jump in torque and a little less Hp? That's a real nice engine for that truck. I owned a 94' and swore it was heavier then it was supposed to be.....at least it drove that way...lol. I think your customer will be thrilled with the performance your engine will provide.
           
        • PanGasket

          PanGasket has cork sides

          Messages:
          4,625
          Likes Received:
          64
          Joined:
          Mar 16, 2010
          Location:
          Gainesville, GA
          Local Time:
          12:50 AM
          Either way, nicely built engine. you may wanna clean the humming bird off the pistons. coulda bumped up comp :toothy10:
           
        • txstang84

          txstang84 Well-Known Member

          Messages:
          4,478
          Likes Received:
          407
          Joined:
          Oct 10, 2011
          Location:
          Abilene, TX
          Local Time:
          6:50 PM
          Bravo Alpha! Awesome torque curve!
           
        • crackedback

          crackedback FABO Gold Member FABO Gold Member

          Messages:
          17,999
          Likes Received:
          2131
          Joined:
          Aug 7, 2005
          Location:
          92201
          Local Time:
          9:50 PM
          Or turn the idle WAY down! Easier if it's a stick.

          Solid runner for sure.
           
        • RustyRatRod

          RustyRatRod 30 Degrees Outta Whack FABO Gold Member

          Messages:
          49,179
          Likes Received:
          15383
          Joined:
          Jun 7, 2010
          Location:
          Georgia
          Local Time:
          12:50 AM
          Wonder what it would do in a Dart with 4.10s? Piss lotsa people off, I bet.
           
        • txstang84

          txstang84 Well-Known Member

          Messages:
          4,478
          Likes Received:
          407
          Joined:
          Oct 10, 2011
          Location:
          Abilene, TX
          Local Time:
          6:50 PM
          That in a Dart with 4.10s would indeed piss off a few folks, and probably leave an ear to ear grin on the driver's face. I'd gladly have it in my Scamp
           
        • skrews

          skrews Well-Known Member

          Messages:
          1,252
          Likes Received:
          611
          Joined:
          Jul 20, 2012
          Location:
          Washington state
          Local Time:
          9:50 PM
          Damn near 400 HP out of ported OE Magnum castings. Very nice.
           
        • RustyRatRod

          RustyRatRod 30 Degrees Outta Whack FABO Gold Member

          Messages:
          49,179
          Likes Received:
          15383
          Joined:
          Jun 7, 2010
          Location:
          Georgia
          Local Time:
          12:50 AM
          It is 400 HP I bet. Just twist it a little more. lol
           
        • mcnoople

          mcnoople Well-Known Member

          Messages:
          742
          Likes Received:
          14
          Joined:
          Mar 11, 2012
          Location:
          illinois
          Local Time:
          11:50 PM
          People want a lope for the same reason they put a 6 inch lift kit on a truck that will never even get driven through grass.
           
        • Idaho

          Idaho Well-Known Member

          Messages:
          2,279
          Likes Received:
          86
          Joined:
          Oct 17, 2006
          Local Time:
          9:50 PM
          Interesting... recently finished up a shortened 8.8 with .410s for my Dart. I've got a junkyard 5.9 and a set of RHS heads waiting to go on. I'm hoping that combo will piss lotsa people off :D

          I have to admit I want the lopey idle... was considering a thumpr (oh the shame :angry7:) but tire burnin low end grunt is the first priority. It's getting a 4 speed, so maybe idle turned down and the right exhaust will do it for me.

          IQ thanks for posting.
           
        • crackedback

          crackedback FABO Gold Member FABO Gold Member

          Messages:
          17,999
          Likes Received:
          2131
          Joined:
          Aug 7, 2005
          Location:
          92201
          Local Time:
          9:50 PM
          Put some 2.5" tubes, noisy turbo muffs and no crossover of any kind and it will sound choppier.
           
          • Like Like x 1
          • IQ52

            IQ52 Well-Known Member

            Messages:
            2,267
            Likes Received:
            1462
            Joined:
            Jul 30, 2011
            Location:
            Idaho
            Local Time:
            10:50 PM
            Here ya go Rob, my favorite run from today. After removing the Summit Racing $129.97 headers, we put on the Pace Setter Performance long tube headers part number 70-2213 that he is going to use on his truck.

            Lost a little torque on the bottom going from 1-5/8 to 1-3/4 tubes.

            Put on an Edelbrock Performer 1407 carb and started leaning 'er down. WOW did we have to lean it down!

            RPM................TQ/HP

            2600..............365/181
            3000..............383/218
            3200..............402/245
            3500..............409/272
            4000..............415/316
            4500..............419/359
            5000..............408/389
            5100..............407/396
            5200..............400/396
            5300..............395/398 GO BABY.......GO!
            5400..............392/402
            5500..............386/405
            5600..............370/405

            We had one run at 413 horsepower and never could back it up, but half-a-dozen runs today went over 400 HP.
             
          • Rockerdude

            Rockerdude Rock n' Roll and A-bodies

            Messages:
            2,392
            Likes Received:
            96
            Joined:
            Aug 10, 2007
            Location:
            Arizona
            Local Time:
            11:50 PM
            Damn that thing is strong. Great job!
             
          • skrews

            skrews Well-Known Member

            Messages:
            1,252
            Likes Received:
            611
            Joined:
            Jul 20, 2012
            Location:
            Washington state
            Local Time:
            9:50 PM
            How much port work was in the heads ?
             
          • Woods74

            Woods74 Quick Senior

            Messages:
            6,004
            Likes Received:
            216
            Joined:
            Aug 21, 2010
            Location:
            Seattle, WA
            Local Time:
            9:50 PM
            Don't forget the fact it rev's faster. I keep tellin y'all Magnums are the way. Most act like they don't exist.
             
            • Like Like x 1
            1. This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
              By continuing to use this site, you are consenting to our use of cookies.