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Topic Review (Newest First)

  • 03-08-2008, 01:03 PM
    Some Kind Of Monster
    Quote Originally Posted by 396_Ways_To_Spit View Post



    That scoop is old school. You need to step up to a Dooley
    Newsflash:
    Most of the boats we run are from the 70's! That's pretty oldschool! I actually want to step up to a fiberglass scoop.
  • 03-08-2008, 12:48 PM
    396_Ways_To_Spit
    Quote Originally Posted by Some Kind Of Monster View Post
    I might sell the butterfly scoop because I think it restricts flow also. .




    That scoop is old school. You need to step up to a Dooley
  • 03-07-2008, 11:46 AM
    Jerkizoid

    Well good news for me Thanks SteelComp!

    Out of desperation, I run a Wiend single dominator tunnel ram on my 049 modified heads. In comparison, I was pulling 6800 with a Dart single open. Now with a different prop (more bite) , I run 6500 with the tunnel and its all the torque my weak little fingers and bad eyesight can handle. This sled 2400 lb Aquacraft runs 84mph at 6000! This is plenty for an old man trying to adapt to the 80 mph clsss! The carb is an 830 with the dominator butterfly conversion and HVM style spacer. Fuel distribution is a little difficult to chase with the outside cylinders running a little lean. Stagger jetting helps alot but I dont do much testing, just racing in circles. Oh this is a 12-1 468 with a small 600 lift low end camshaft. I love to make cheap junk work enough to win races. Of course the competition would be way tougher if I was in division 12! Great info for poor dudes like me. Thanks!

    PS Havent manifold designers been mis matching ports for years to gain bottom end? Wont the intake air swirl somewhat when it hits the oval port? Swirling adds velocity and atomization, yes, no? Anyone try the screen at the intake gasket area to do the same?? Of course Dyno info would be nice! Did I miss these results? jErK
  • 03-06-2008, 03:16 PM
    Some Kind Of Monster
    Quote Originally Posted by cfm View Post
    To answer your last two questions: airflow !

    Dual plane has split plenum and longer runners for better low-mid rpm power. The Air Gap RPM has larger plenum and runners that help it breate more than normal dual planes. thus why a very effective intake manifold. However, it will become a restriction at some point, which your engine will surpass. If you built a sub 6krpm sub 10.5:1 454 I would say RPM Air Gap also. Although, the Dart oval would still be a tad better there too.

    You are at 12:1 compression brother. Give it what it wants !

    Forget about the rect intake on oval head thing - that was yesteryear when there where no decent flowing dual planes for even mild oval port headed engines. There where for rect ports - thus the rect intake on oval head. So..........forget about that stuff. We are way past those years in technology and parts availability. Oh, fyi: many have used the oval Dart single plane on rect port heads very effectively.
    That's the info I was looking for. Looks like I will be looking for the Dart intake. Maybe I can find one on ebay that I can blast and clean up. They don't look cheap so I'll be selling a few parts to pay for it. I might sell the butterfly scoop because I think it restricts flow also. I suppose that would pay for it right there.
  • 03-06-2008, 03:02 PM
    cfm
    To answer your last two questions: airflow !

    Dual plane has split plenum and longer runners for better low-mid rpm power. The Air Gap RPM has larger plenum and runners that help it breate more than normal dual planes. thus why a very effective intake manifold. However, it will become a restriction at some point, which your engine will surpass. If you built a sub 6krpm sub 10.5:1 454 I would say RPM Air Gap also. Although, the Dart oval would still be a tad better there too.

    You are at 12:1 compression brother. Give it what it wants !

    Forget about the rect intake on oval head thing - that was yesteryear when there where no decent flowing dual planes for even mild oval port headed engines. There where for rect ports - thus the rect intake on oval head. So..........forget about that stuff. We are way past those years in technology and parts availability. Oh, fyi: many have used the oval Dart single plane on rect port heads very effectively.
  • 03-06-2008, 02:49 PM
    Some Kind Of Monster
    Also I am still curious what are the specific applications for both single and dual plane manifolds?
  • 03-06-2008, 02:46 PM
    Some Kind Of Monster
    Quote Originally Posted by cfm View Post
    The Performer 2-0 was designed for low rpm low compression truck motors.
    I couldn't even imagine this on a 12:1 motor.

    Jeesh, even on the 8:1 peanut port 330hp Merc motors, the Edelbrock Rpm pulls more rpms than the Performer 2-0.

    Wow, are you going to be thrilled. If you aren't you have issues somewhere else - engine wise or just mentally. LOL.

    Hope you have a big flame arrestor !
    Hmmm, I knew it was a weak link on my engine, but it was all I had at the time of build. The engine runs great right now but I know it has a lot more left in it if I play with some things. All my cam #'s are in my Hotboat PMs and at home so I don't have that off hand.

    So do I stick with oval port and rework the intake for a gasket match, or try rectangle?
  • 03-06-2008, 02:22 PM
    cfm
    The Performer 2-0 was designed for low rpm low compression truck motors.
    I couldn't even imagine this on a 12:1 motor.

    Jeesh, even on the 8:1 peanut port 330hp Merc motors, the Edelbrock Rpm pulls more rpms than the Performer 2-0.

    Wow, are you going to be thrilled. If you aren't you have issues somewhere else - engine wise or just mentally. LOL.

    Hope you have a big flame arrestor !
  • 03-06-2008, 02:16 PM
    cfm
    I've used them even on 8.5:1- 9:1 relatively big cammed oval port 454's and they don't lose any power at 4k, at 5k it starts to edge out the good dual planes, and from 5k up it kicks ass.

    Your compression is way up there and with oval port heads I would not be concerned about any low speed power loss. You want to really take advantage of that compression and cid and let'r rip.

    What cam specs are we runnin' ?
  • 03-06-2008, 01:41 PM
    Some Kind Of Monster
    Quote Originally Posted by cfm View Post
    Dart Oval Port Single Plane !!!!
    Any reason why?? Impatient 1 says RPM air gap. Which is better and why?
  • 03-06-2008, 12:36 PM
    cfm
    Dart Oval Port Single Plane !!!!
  • 03-06-2008, 12:29 PM
    Some Kind Of Monster
    Quote Originally Posted by IMPATIENT 1 View Post
    what kinda of dual plane are you currently runnin? rpm intakes are that shiat for a heavier lake jet that's only gonna run up to 6200-6500tops. ran a rpm bbf intakes on my sj, sc, a buds sanger sj 557bbf, and a have recommended it to a few others with bbc and they had really good things to say also.
    Right now I have an Edelbrock Performer 2-0 topped by an 850 dp. It's a 468 Chev running 12:1 comp. I see up to 6k RPM but I am always trying for more (of course).

    FYI they are 781 oval port heads that have oversized valves and have been worked a bit. I'm also considering the RPM square port just like Hotbo was. Opinions?
  • 03-06-2008, 11:48 AM
    IMPATIENT 1
    here's more info on the rpm oval port intake. sounds like 100 plus shipping is a hella deal compared to a new price

    http://store.summitracing.com/partde...1&autoview=sku

    better hurry quik if you're wanting it, little birdy told me hotbo bought a tx-19 this week and is putting the sj up for sale
  • 03-06-2008, 11:45 AM
    IMPATIENT 1
    Quote Originally Posted by Some Kind Of Monster View Post
    Ok, I'm considering the intake for my engine.

    Somewhat along the same lines here.. What applications are the single and dual plane intakes better suited for? How do I know which will be better for my mill? I'm running a dual plane and wondering if I should be running a single?
    what kinda of dual plane are you currently runnin? rpm intakes are that shiat for a heavier lake jet that's only gonna run up to 6200-6500tops. ran a rpm bbf intakes on my sj, sc, a buds sanger sj 557bbf, and a have recommended it to a few others with bbc and they had really good things to say also.
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