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Topic Review (Newest First)

  • 11-10-2009, 10:30 AM
    STV_Keith
    I'm hoping there is already a solution out there that people could buy. Anyone?
  • 11-09-2009, 07:19 PM
    71hallett
    Quote Originally Posted by STV_Keith View Post
    I have found them for the older motors (83-02), but not for the newest generation of motors (496 Mag, 496 HO, 500HP, etc)
    If your stuck I could make you one.
  • 11-09-2009, 04:47 PM
    STV_Keith
    I have found them for the older motors (83-02), but not for the newest generation of motors (496 Mag, 496 HO, 500HP, etc)
  • 11-09-2009, 04:31 PM
    Outlaw
    I have seen spacers made with a provision for the sensor that is added between the manifold and riser
  • 11-09-2009, 04:14 PM
    STV_Keith
    Thought this might be the right place to ask. Does someone make an O2 adapter plate for stock manifolds on like a 496 Mag or 496 HO, 500HP, etc?
  • 04-26-2008, 08:13 AM
    619 public nuisance
    Quote Originally Posted by 76Miller View Post
    That sounds pretty mild Is this the #509 boat ???
    It is Scott Lumberts old PC...619 Bes set it up to be conservitive,plenty of HP and still lives...These are dyno #...
  • 04-25-2008, 08:46 PM
    76Miller
    Quote Originally Posted by 619 public nuisance View Post
    598 cu in, idle to 7800 rpm's 12.6,with 500 squeez nos 11.0 .
    That sounds pretty mild Is this the #509 boat ???
  • 04-25-2008, 08:44 PM
    WETTE VETTE
    What do you guys suggest for NA marine engines? I have an innovate O2 on my NA 598 and have it tuned for approximately 12.7 at WOT. Cruising is 13.0 and idle is hard to comprehend because I think I am pulling raw air in during overlap and the readings are off. It idles great at 900 RPM and the A/F reads 14-17 and is sporadic. The cam is a healthy solid roller so pulling some fresh air in at overlap isn't really a surprise. I have heard 12.8 - 13.2 is ideal for NA marine stuff and want to hear other opinions.

    Thanks,

    Craig
  • 04-25-2008, 12:25 PM
    619 public nuisance
    Quote Originally Posted by JAY4SPEED View Post
    Great info, thanks!

    What are your AFR figures with an unboosted engine at load and WOT?

    Jay
    598 cu in, idle to 7800 rpm's 12.6,with 500 squeez nos 11.0 .
  • 04-18-2008, 10:15 AM
    scarabrick
    Buy one of these

    http://www.innovatemotorsports.com/products/MTS.php

    We have the "G2"

    BD marine is dead on

    OURS.........

    540 ci

    13.2-13.5 idle
    12.5 from 1000 rpm's to 5600 rpm's

    4.5 power valves in a dom"marine"
    93 squares

    Power valves open up at 4200-4400 (verified with vaccume guage in spacer under carb)
    Great for cruising gas mph and still rich enough so you don't burn a piston
  • 04-15-2008, 07:21 AM
    Warp Speed
    Quote Originally Posted by 71hallett View Post
    You could be rattling away and your a/f is still good.
    True, but you could be "rattling away" and still not see it with the egt data either.
    Can't remember the last time we used them. Now that doesn't mean they are totaly useless, but I think they are just not as useful as we once assumed.
    Kinda like jetting with BSFC, too many variables effecting the reading to rely on them for tuning.
  • 04-15-2008, 06:11 AM
    71hallett
    Quote Originally Posted by Warp Speed View Post
    Why would you rather tune with an EGT?
    Sorry, wanted to see if anyone else would reply. We use an a/f but it will tell you nothing about timming or the quality of the fuel you just bought. Egt will. You could be rattling away and your a/f is still good.
  • 03-25-2008, 09:35 AM
    BDMarine
    Quote Originally Posted by JAY4SPEED View Post
    Great info, thanks!

    What are your AFR figures with an unboosted engine at load and WOT?

    Jay
    Normally aspirated engines are a lot more finicky in their tuning. There are so many things that determine what they like. Cast iron or aluminum heads, compression, lobe seperation, etc. Lets say it's a 540 BBC with alum heads and 9.75:1 compression with 91 octane. I would start at 12.7 - 12.8 and adjust from there.
  • 03-24-2008, 11:09 PM
    JAY4SPEED
    Quote Originally Posted by BDMarine View Post
    Here's what we do.
    Idle 13.5 to 13.8
    Accelerate 12.2 - 12.5
    Cruise no load no boost 13.0 - 13.3
    Cruise with small amount of boost and load 12.5 - 12.7
    WOT 7 - 8 lbs boost 11.8 - 12.0

    These are good general numbers. ALL these numbers will be adjusted depending on what the engine likes. We still look at plugs also.
    Great info, thanks!

    What are your AFR figures with an unboosted engine at load and WOT?

    Jay
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