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Long ram intakes. Solid rollercam. 496" Stroker...

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  • Long ram intakes. Solid rollercam. 496" Stroker...

    Yesterday I re-installed the long ram-intake system back on the engine of my '60 NewYorker.
    I had put them aside a while back and used a single carb intake in the mean time, after I had installed a nice little solid rollercam in the engine, and performed a drum-to-discbrake conversion on the car aswell.

    Today I got around to startup the engine again to tune the carbs.
    I still have some work to do 'cause I'm faced with a surging issue at idle. Probably a mis-adjustment between both carbs still.
    But already I've found the motor sounds why crisper with this cam then it did with it's pretty much stockish cam before.






    www.BigBlockMopar.com

  • #2
    And new brakes? That's wise

    Do you think the engine will be able to pull hard at higher rpm with the long intake?
    My fabulous web page

    "If it don't go, chrome it!" --Stroker McGurk

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    • #3
      Im drooling...
      Ive always loved the Sonoramic long ram systems. They work great in MPI form too! Eliminates the warm up puddling in the intake and allows you to ditch the heater tubes from the exhaust to the intake. Herman would know this for sure but I think the Long Sonoramic system is a bit restrictive at the top end. The "Short" Sonoramic tubes hav a joined Plenum from the carb to about half way down to the heads, and those, while even rarer, supposedly made the numbers at the top (5500 rpm or so). The passing power at 3800 rpm or so with the long tubes was unstoppable. I think the motors were specd at 325 hp and 435ft lbs or something like that...2+ tons of fun
      BKB
      www.FBthrottlebodies.com
      Bruce K Bridges

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      • #4
        When I started on the cam-swap a while back, I deliberately cut the main brakeline coming from the single pot MC in half.
        This was to prevent myself from getting tempted to run the car with the front drumbrakes after the rollercam was installed. I know myself.
        The drums were working fairly good on this car, but were not sufficient for repeated braking during 'speedtrials'.

        With the stockish cam there were 1.6 rockers on the Edelbrock heads, in favor of the 1.5 ratio rockers which come stock on Mopar engines. With the .570" lift rollercam now in the block I switched back to 1.5 rockers.
        The motor pulled hard with the stockish cam and it had a good amount of torque. It made the 4500 lbs car feel like you were driving a small pony-car. Even with 3.23:1 gears.

        I've got my Innovate O2-gauge installed in the car at the moment, to help get a better tune with the carbs. But I'm thinking of getting myself a second O2-gauge and sensor so I can adjust both carbs properly at the same time.
        www.BigBlockMopar.com

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        • #5
          Mopar drums were always a little stingy on the whoa.
          I would love to see a chassis dyno sheet for that combo.
          BKB
          www.FBthrottlebodies.com
          Bruce K Bridges

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          • #6
            I've had this car on the track a couple of years ago, but due to driveline-vibrations I couldn't run the 1/4 at fullthrottle. But at the 1/8 the car made a 8.6sec ET. It had 3.9 gears and did a 1.6 60'.

            I'm sure the smallish tubes are restrictive at higher rpms. But the exhaust is equally restrictive with it's shorty headers and 2.5" system all the way back. Got 2 Dynomax mufflers and 2 resonators after the rearaxle.

            The added torque these longrams help making during the lower rpms is indeed so much fun on the street, the high rpm characteristics of the engine don't really matter for me.
            www.BigBlockMopar.com

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            • #7
              That is an awesome setup BBM!!!!!!

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              • #8
                Originally posted by BigBlockMopar View Post
                I've got my Innovate O2-gauge installed in the car at the moment, to help get a better tune with the carbs. But I'm thinking of getting myself a second O2-gauge and sensor so I can adjust both carbs properly at the same time.
                That's one of the few engines that have one carb feeding one exhaust pipe.

                Should be fun!
                My fabulous web page

                "If it don't go, chrome it!" --Stroker McGurk

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                • #9
                  There is a large balance tube running between both intakes but that's mostly for equalizing the vacuum.
                  Certain things pop up that need some tweaking still, like the stock brakebooster has a very slight leakage when the brake are applied. So if I connect the booster vacuumline to just 1 carb, it disrupts that carb's tune. Originally one of the tubes has a vacuumfitting for this, but I don't like one cylinder receiving a leaned out mixture.
                  Because of this I created a vacuum-fitting in the balance tube. I also want to connect the PCV to that and pull ignition advance from it.

                  Also, someone made up the 'new' carb-linkage around the original bellcrank in the center. But they used aluminium tubing for this. Although it's nice and light, it also expands when heated, causing the engine's rpm to increase some aswell.


                  When I got this combo up and running to my liking again I plan to put it on a dyno to see what comes out of this.

                  This would indeed be a fun project to 'EFI'.
                  I've seen a pic of an EFI'd 'short' longram system in progress years ago. Never saw any further info or heard how it ran unfortunatly.


                  Last edited by BigBlockMopar; July 14, 2012, 04:00 AM.
                  www.BigBlockMopar.com

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                  • #10
                    Spent some time with the engine today but I couldn't tackle the stubborn idle-surging the engine is experiencing. It pretty much sounds like a surging blower-motor now. When I give it some throttle and it disappears.
                    I disconnected all the linkage and made sure both carbs idle-speed adjusters were backed out. Turned them in, just until the throttle blade barely started moving. Did this on both carbs. Then reconnected the linkage.
                    Tuned the idle by turning both idle-adjusters an equal amount. Did the same for the mixture screws.
                    Engine still surges. Even with the linkage disconnected again.
                    With adjusting idle-speed per carb I couldn't get rid of it either. I'm thinking there's another issue here.

                    Checked for vacuumleaks. Disconnected the PCV and brakebooster. This had an effect on the AFRs, but not on the surging.
                    Also checked timing during the surging for possible mech. advance kicking in already, but it was steady.

                    So, I think I could use some help here.
                    The longram intakes have performed perfectly before on this engine. But since the roller cam-swap it doesn't like to idle nicely anymore. I know the fairly big-ish cam has a lope to it. That I don't mind. But I need to get rid of the surging.
                    Cam specs are as follows:
                    CompCam XR274R-10 - Mechanical Roller
                    Advertised Duration 274/280, Lift .564/.570

                    I will get myself a 2nd AFR gauge and hook it up to the other exhaust-pipe.
                    I had a vacuumgauge mounted earlier, it hovered around 14-18 during idling.

                    Been reading up on this surging issue a bit, and I noticed some modify the carbs and drill tiny holes in the primary throttle blades to get some added airflow again across the idle-slots.
                    Would this be a smart thing to do 'already'?
                    It's not that I 'have' to increase the rpms to even get it to run properly.

                    Got some video of the engine running which I will put on YouTube shortly.
                    Last edited by BigBlockMopar; July 15, 2012, 12:18 PM.
                    www.BigBlockMopar.com

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                    • #11
                      Drilling the throttle plates might help, if you had to open them more with the new cam to set the idle speed.

                      I don't know why you need to eliminate the surge, but then I have a blower so I'm used to it.

                      What do the AFRs do when it is surging?
                      My fabulous web page

                      "If it don't go, chrome it!" --Stroker McGurk

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                      • #12
                        AFR hovers between 13.5 and 15's during the rpm up- and downs.
                        I tried to richen up the carbs, but even with lower AFRs (highs under 14.5) the surging is still present.
                        (The AFR-gauge is currently sampling the driversside exhaust/Pass.side carb).

                        Forgot to mention, (I don't 'really' mind the surge) but when I put it in Drive, I have to keep it from stalling.
                        With a tad throttle, I can have it idle in Drive, but the surging is worse then. The engine really pushes up against the brakes. (Stock stallconvertor)
                        With more throttle the surge goes away (engine runs on primaries then).
                        Last edited by BigBlockMopar; July 15, 2012, 12:28 PM.
                        www.BigBlockMopar.com

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                        • #13
                          That's a rather lean idle....hmmm.....
                          My fabulous web page

                          "If it don't go, chrome it!" --Stroker McGurk

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                          • #14
                            I've had the idle AFRs going from 12-14 aswell... Still surging.
                            But I tried to keep it on the lean side to prevent loading up the plugs. Changing/cleaning plugs on this engine is not my cup of fun I can tell you.

                            Here are the 2 clips I made of the engine idling...




                            www.BigBlockMopar.com

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                            • #15
                              It's leaning way, way out. I'd look for vacuum leaks. Probably the cause of surge too.
                              BS'er formally known as Rebeldryver

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