Port nozzle size stagger

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by MKR-588, Oct 26, 2008.

  1. ITS IN MY BLOOD

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    Why not try this for thought,..
    You have two cylinders that are too lean,... your system already has
    ample fuel, your fuel pressure is in the ok range,..so why wouldnt you determine which of the other cylinders are colder (or rich), and put a smaller nozzle in them,..??? that would put more fuel into the two lean cylinders, and also increase fuel pressure too, and still be getting the same amount of fuel to the motor. if you have egt`s thats a big helper in itself as long as the system is fairly close to begin with. getting the balance correct is the objective without sacraficing fuel delivery and burnt pistons.
    Just bored
    Vic
     
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  2. WJ Birmingham

    WJ Birmingham New Member

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    Vic;

    We had an error in the last test 'n tune I went to. A pit guy didn't tell me that when he pulled #2 & #4 plug wires off, they weren't pushed on all the way. I leaned 2/4 out based on the EGT's from the prior run (stupidity, without checking the EGTs on the pass before that).

    Due to this, the #2 went WAY lean, at 1660F, tulipping the intake valve. I've gotten that $125.00 mistake fixed, and back together. But, I now need to go back to the old tune up (before frying the valve) to see where I need to go with the plug wires properly secured.

    But yes, I agree, if two cylinders were fat, and 2 were lean, it'd be easy to swap nozzles around to get the proper distribution without changing pressure or total GPM to the system.

    Mark;

    Since you called me out on my pump size. I believe in 1/3 overage on the pump capabilities. While 17.3 GPM might be a lot at 26 PSI (10.1 GPM), and moderately oversized at 33 PSI (10.8 GPM) , when I crank the blower up to 35-40% OD (where I desire to run it), 11.4 GPM is about 66% of the 17.3 pump I have. This will allow me to run a 50 jet in the pump bypass, keeping the main jet around 100. This should also get my system pressure into the 110 PSI range. I can step down a couple nozzles in the ports (which I have plenty of nozzles for) to increase the system pressure into the 125 degree range.

    Again, this shit isn't that tough. I dont know why everyone pretends like it is. It's simple math and common sense.
     
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  3. Lorenzo

    Lorenzo New Member

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    We've been telling him this for years :p
    WJ I gota use that one, that right there is some funny shit,
    Hey Grumpy old man They make pills for that rope problem :eek: Damn that's a scary thought.
     
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  4. john348

    john348 Top Alcohol

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    maybe so;
    But i have seen the files that Gerardot has kept from 30+ years of doing fuel systems on a wet bench, he can get you very close:, you would be very impressed of the who's who of names that have had their stuff there or made there :D:D
     
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  5. blown375

    blown375 New Member

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    Sometimes the most expensive help or advise is... FREE !
     
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  6. mark6052

    mark6052 Member

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    not "calling out" anybody wj. but you are a good example of somebody that "read" a book and missed the point. you personally think you need a 1/3 extra amount of fuel supply? funny, guys run alot smaller pump, like a 15gal, and get the pressure up above 125. like 150ish and run very safe. you are like many I have seen run way to big a pump and get lost in the flow. not putting you down, just stating fact. sorry if you cant take alittle input different than your ego:( now please , lets not get in a pissing contset. for the amount of money spent "buying" atune has helped alot of guys get on target alot quicker. you maybe the exception.
     
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  7. MKR-588

    MKR-588 Member

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    Take that WJ, anyway guys back to the point in hand. If the blower was set back say another 2-3 inches, would this make the air distribution a little more even in the manifold thus allowing the port nozzles to even up a bit more.How much more work are the front cylinders doing compared to the rear? Do the fabricated manifolds help in this situation?
     
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  8. eli

    eli Banned

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    So, I took the time to check out your fuel system, According to your post of the nozzles you use you are running 62% threw the blower and 38% threw the port nozzles,Should be 70% --30%, See i'm not so bad, Now go home and get your shoeshine box, and send your system out to be flowed before you burn up more shit. P/S where did you get $100.00 for a flowed nozzle? some one is yanking your chain. By the way that book, is that the one that tells you you can get 5,000 HP with alky? And did you get there yet? :p;):D
     
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    Last edited: Oct 28, 2008
  9. WJ Birmingham

    WJ Birmingham New Member

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    Ya know, you're absolutely right. I'm a nobody and a know nothing.

    I'll just sit back and read the site for the entertainment value it provides.

    Guys like Eli who have forgotten more than I'll ever know (never forgotten about how to be an ass) can continue to criticize anyone who thinks outside of the box.

    Peace...
     
    #29
  10. eli

    eli Banned

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    The guys that flow these systems have flow benches and a lot of data, I'm not criticizing you just letting you know that your system is flawed, lots of people don't have the mathematical skills you have and wouldn't be able to do what you did, so thats why they are told to send it to a pro. Outside the box? the INTERNET made the box two big to be outside it! as far as being an ass, No, I'm a PRICK, ask anyone that knows me. he he he. :D :) :p
     
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  11. ZERO260IN1

    ZERO260IN1 Member

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    Make me understand your logic.

    WJ’s pump is flowed, he knows his GPM of his pump and the pressure in his system. Now he is tuning by watching his plugs and EGT's. He’s on his way.
    At this point...Telling him to get his system flowed is ridiculous. Flowing his system doesn’t give him a tune up, it gives him data of HIS system, (that he already has) to keep the "math" right during the tuning.

    If its running 'okay' and he's pulling plugs and knowing what to look for, NOONE can improve on his tuning unless they are there with him looking at his plugs.
     
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  12. MKR-588

    MKR-588 Member

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    I remember in a previous thread that WJ gave me a little shi# that I was putting too much fuel through the blower. Now Eli is saying that you need 70% thru the blower & 30% thru the ports.Whats the problem with say a 60 - 40 split or even less thru the blower ?Looking to be educated please
     
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  13. eli

    eli Banned

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    The more fuel run thru the blower the cooler the charge, a roots blower after a certan point is just heating up the air, ever hear the saying your full of hot air? :D The motor don't like hot air, the colder the charge the more power you make, by the way you are the origanel poster on this tread, my question to you, Is this a K- Boat 18-19 foot flat bottom tune up your looking for?:)
     
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  14. MKR-588

    MKR-588 Member

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    Eli, a 21 ft v hull. Not really looking for a tune as much as trying to see what is normal. You will never get a top tune unless you work on it. The best way to learn is when you hurt parts, that way you won't do it again. We have been sneeking up on it as we had the blower re-stripped & ran it only 25% with 20 lbs boost @ 7500 rpm.The tune is reasonably safe as we are trying to get them even as possible & safe before we turn the blower faster. The 2 front cylinders are much hotter than the rear and was curious just how much stagger guys are running. We now have 59 in the front down to 45 @ the rear. Maybe a bad manifold too ?
     
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  15. eli

    eli Banned

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    Is your hat on backwards? and is the motor in with the front to the front of the boat? I'm tuneing a 18 foot k-boat flat bottom, you cant use a drag strip tune up in a flat bottom. where only using a 8/71 at 3 teet over( 11 % ) 9 lbs and the driver is afraid of it. try this site it may help. http://www.fuelinjectionenterprises.com/supercharged.htm
     
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    Last edited: Oct 30, 2008
  16. ALKY4sure

    ALKY4sure New Member

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    "we had the blower re-stripped & ran it only 25% with 20 lbs boost @ 7500 rpm.The tune is reasonably safe as we are trying to get them even as possible & safe before we turn the blower faster."


    I would put the blower at the maximum overdrive you intend to run at, the fuel way on the safe side and work down from there. The distribution you find now at this overdrive will more than likely not be the same with more overdrive. Manifold turbulence will definitely change how and where the fuel flows through the manifold and exactly which ports end up with more or less fuel. So you'll end up right back where you are now, chasing nozzles.
     
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  17. MKR-588

    MKR-588 Member

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    Eli, the motor is in backwards, we run a 'v' drive and the hat is facing forward or you can say the hat is backwards compared to the motor.

    ALKI,Just figured that if we are way safe with what we have now then we can up the OD say 5% then check the system again & adjust as neccasary. Thinking to take things slowly and surley & will log all the changes as we go along for future records.
     
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  18. eli

    eli Banned

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    How do you keep the spray from the other boats from going into your motor?
     
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  19. Mike Canter

    Mike Canter Top Dragster

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    Be the guy in the lead
     
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