Speedmaster Small block porting tips and results

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  1. pittsburghracer

    pittsburghracer Well-Known Member

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    I finally bolted one of my heads down on the flowbench today and got some numbers. I bought mine bare so these numbers are with one used Edelbrock exhaust valve and one used 2.02 Edelbrock intake valve with a 30 degree backcut added. Other than that as out of box

    .100——55
    .200——131
    .300——185
    .400——-235
    .450——-247
    .500——-240. Numbers backing up
    .600——-246
    .700——-256-262 turbulence
     
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    • 318willrun

      318willrun Roadkill '80 D150

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      These results are for the "unported heads"... not the cnc'd heads, correct?
       
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      • PRH

        PRH Well-Known Member

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        Might not have had that spike(or less of a spike) @.450 without the back cut on the valve?
         
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        • pittsburghracer

          pittsburghracer Well-Known Member

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          After that test I added a 30 degree and 15 degree cut to the factory 60 and 30 seat cuts from the factory. I then widened the .930 measurement at the pushrod pinch to the 1.015 measurements given to me from the cnc’d heads from Speedmaster. I then removed the slight overhang right before the seat on the shortside. I then took a 40 grit sanding roll to the whole port and mounted it for my second flow test. Before and after number side by side.
          Before—————-after
          .100——55——————65
          .200——131—————137
          .300——185—————-194
          .400——235—————-240
          .450——247
          .500——240—————250
          .600——246—————265
          .700——256-262———263

          .
           
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          • K.O. SWINGER

            K.O. SWINGER Well-Known Member

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            Those are very respectable numbers for a high performance small block Mopar Head low lift number are better than a W-2 to 400 correct me if I'm wrong
             
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            • pittsburghracer

              pittsburghracer Well-Known Member

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              8CE6AEA5-8FC4-4441-963C-02B82B73F8B1.jpeg 94E3ECB3-45EB-4D5C-96FA-31775572EBCE.jpeg 70A651C8-2E20-4856-A3CB-76C18A0A7BC1.jpeg The common wall needs straighten and that Damn ugly bulge for the head bolt goes next along with some chamber work. I have airspeeds both before and after and will drawl a diagram with the numbers ASAP. I usually tube the pushrod to grab more volume and for anyone looking to do so all that is needed is a tubing cutter, JBweld, 17/32 K&S tubing available at Ace Hardware or Amazon for around 5.50 for a 10 inch piece.
               
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              • pittsburghracer

                pittsburghracer Well-Known Member

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                B6BD76AD-3F4A-4065-BB96-991E108CE4E4.jpeg 3A6367FD-3DD8-4300-9E6B-5EEA999DB008.jpeg 1CD320E5-AA6A-4642-BE12-26F4C4B82C7F.jpeg 22C6D5D5-770F-4119-930C-F472E9CB4397.jpeg
                 
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                • pittsburghracer

                  pittsburghracer Well-Known Member

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                  The only number I remember from my stock W2 heads were 260cfm@.450 then they fell on there face. But that was easily rectified
                   
                • pittsburghracer

                  pittsburghracer Well-Known Member

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                  Correct.
                   
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                  • K.O. SWINGER

                    K.O. SWINGER Well-Known Member

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                    :thumbsup::thumbsup:Wow, you're the man I have been running as cast speedmasters with a 4 angle valve job for about 3 years now they've been a great little head but I will definitely be watching your work. Thank you
                     
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                    • K.O. SWINGER

                      K.O. SWINGER Well-Known Member

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                      Screenshot_2019-12-26-17-20-46.png
                       
                    • K.O. SWINGER

                      K.O. SWINGER Well-Known Member

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                      Don't get me wrong there no W-2s but they're a good little head and I will love to see their potential
                       
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                      • abdywgn

                        abdywgn dismantler

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                        can you sleeve the head bolt hole and if so, how is that done?
                         
                      • pittsburghracer

                        pittsburghracer Well-Known Member

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                        The hole is under 9/16 but bigger than 1/2 for the 1/2 inch bolts. The factory bolts are back cut so that oil can get to the rockers. With a 1/2 inch stud things get tighter so I run a 9/16 drill bit through the hole and use 9/16 K&S brass tubing and put a small coat of JBweld on it also. Just don’t forget to redrill the two holes for rocker oiling after the JB weld sets
                         
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                        • pittsburghracer

                          pittsburghracer Well-Known Member

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                          Ok here are some before and after airspeed numbers. Let me begin to say mine maxes out at 401 foot per second which is crazy fast. I’ve found that anything over 350 at a curve is in the hard to control numbers. What happens is in the case of the short turn if air can’t navigate the turn it will shoot across the turn and crash into the “good air” going across the back of the port and shut it off. These speed numbers are at .500 lift so when you see numbers back up at say .600 lift this is what is going on. The port becomes noisy and numbers back up. Without a flowbench we could never check this and without checking speed numbers we wouldn’t know where to port next for better flow numbers. When you port one area say the shortside and get better numbers you may be able to go back to the pinch and get even better numbers. I call it milking a port. It is time consuming but well worth the effort.
                           
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                          • pittsburghracer

                            pittsburghracer Well-Known Member

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                            0E1070E0-1A8A-4F7B-AB99-70A69AEFE9D1.jpeg 33C271EB-AFAB-441B-8FC9-60891272451A.jpeg Sorry I’m not an artist so I hope you guys understand this.
                             
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                            • j par

                              j par Well-hung Member

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                              So all things being 100% equal as in same car, same track, same atmosphere, same everything.. starting with Speedmaster loaded unCNC'ed heads and a Time slip to to totally custom valves, springs, and Port work what would you like to gain in the quarter mile?..
                               
                            • pittsburghracer

                              pittsburghracer Well-Known Member

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                              9AE880A1-5907-47FF-A3D9-FABEE9244916.jpeg This will be a little harder to understand from my drawling but these are the airspeeds across the bottom of the shortside. Look at how the number jumped on the left side (pushrod) after opening up “the pinch” and letting the air flow tighter against the wall. Now it’s begging for more area at the shortside so I will remove the head bolt bulge and push the common wall over, shape the bowl, and open the combustion chamber up around the valves.
                               
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                              • j par

                                j par Well-hung Member

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                              • pittsburghracer

                                pittsburghracer Well-Known Member

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                                As much as I can!!!
                                 
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                                • j par

                                  j par Well-hung Member

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                                  Well no crap! LOL... So I guess for us Unknowing tightwad Cheapskates who had a set of these sent to our house loaded for $700 if we mailed these off to some Guru and he charged this ungodly amounts absolutely doubling the amount without question what would be really gain at the track?.. I mean they were completely budget-minded in the first place correct? I mean why wouldn't a guy just by Trick flows and be done with it or shockers??. I mean really the normal guy buying Speedmaster isn't trying to set the world on fire with $700... I mean if you were going to spend $1, 500 you would have probably just got the Shockers.. and if you were going to spend 2502 3K you would get the trick flows...
                                  The one place that I called about these heads and having them checked out they said the seats were junk and the valve guides were junk and that would be $800.. that's not even porting them or a nice valve job or anything that's just fixing them according to their phone call...
                                   
                                • j par

                                  j par Well-hung Member

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                                  Which Guru do you believe...
                                   
                                • rumblefish360

                                  rumblefish360 So close, yet so far away FABO Gold Member

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                                  The numbers are at the location in the port, reporting the speed of air. Before and after numbers in pictures, the numbers locations are where there air speed is reported. Top left middle and right side, then on downwards in the middle of the port and then the bottom.

                                  Correct me if I’m wrong Pittsburghracer
                                   
                                • rumblefish360

                                  rumblefish360 So close, yet so far away FABO Gold Member

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                                  You should know that the gain is a totally dependent on the combo and CID of the engine it’s on. The ability to call an amount of HP gain is a bit hard considering the variables.

                                  What you can guesstimate is 2 HP per cfm or flow. It’s a layman’s term, and it’s lame, but it will ball park it for the average guy to what is possible in a good series hot rod build.

                                  It should be entirely possible to exceed this equation without a problem. But at that level, is it a street engine or a race engine? Street ability is strictly driver dependent and what there willing to live with.

                                  A good example I think is the Victor head build done with the modified W2 Pro Dominator tunnel ram with only 376 cubic inches IIRC???
                                   
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                                  • pittsburghracer

                                    pittsburghracer Well-Known Member

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                                    You got it right. I have a probe with a J-turn (180 degree) in it so it goes in the port and faces incoming air. The probe for checking exhaust speed is just a straight probe.
                                     
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