Whats a waste gate for

Discussion in 'Diesel Engines' started by Frosty, May 28, 2007.

  1. Frosty

    Frosty Previous Member

    waste gate-- whats it for? waste of time?
     
  2. StianM
    Joined: May 2006
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    StianM Senior Member

    I supose your talking turbocharging here.

    They are for opening a bypas valve when the Turbo preshure reatch a desired preshure.

    Maybe your engine can't take a higher preshure (octane rating or just mecanical reasons)

    A smaler turbo not being able to provide the same airflow would have some disadvantages and chosing a larger one so you could meintain a desired preshure at max rpm would probartly not deliver anny bost at low rpm.
     
  3. lazeyjack

    lazeyjack Guest

    yeah jack get wiv it man
    blow off valve same thing geezeeeeeeeeee
     
  4. Frosty

    Frosty Previous Member

    So why 'triple' charge turbos if pressure should not get so high?
     
  5. StianM
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    StianM Senior Member

    More HP, but you could not do that to anny engine.

    If you want to turbocharge a gasoline engine you will nead to increase the octane rating or lover the compresion.

    If you turbocharge a diesel you have to hope the piston, crank, rods can stand the preshure.

    I think I heard that those tractor pullers using triple stage turbos weld the top to the block in adition to bolts to preventing it from blowing off.
     
  6. Frosty

    Frosty Previous Member

    Never seen a tractor puller using diesels. Welding what??? Alluminium to cast or cast to cast --Ha ha ha. i think you would blow the crank out onto the tarmac before you would lift the head off.

    Anyway not talking petrol thats different all together.

    Diesel waste gate. A diesel is a hardy motor to begin with, we are talkin a waste gate on one single turbo -why would you want it to blow off?
     
  7. StianM
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    StianM Senior Member

    The engine is designed for a certain cylinder preshure and if it's increased it will be the same as tuning anny other engine. Reduced reabilety and increased service.

    Using a Wastgate make you able to have a bether operational range off the turbo than you would when fitting a turbo that only chanrge optimal at max rpm and load.

    Isota use two turbos for there offshore engines. At low load only one turbo is being used with allow a faster response while at high loads they open a valve that supply the second turbo charger allowing to keep a high preshure.
    This system is mutch more expensive. Called sequensial turbocharging I belive.

    The optimal for a diesel is to have a turbo fitted that match the engines caracter at max load, but not all engines runn at max load all the time.
     
  8. StianM
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    StianM Senior Member

    Would defently be something to try out on the penta:D
     
  9. Frosty

    Frosty Previous Member

    I would imagine that Isota would have therefore taken off thier waste gates.

    You say (quote) at low load only one turbo is being used wich allows for a faster respose.-- Un quote) How does that work then?

    Truck racers triple charge thier motors . I think im sure when I say those road haulage Volvos werent designed for triple charging. But triple they do.

    For racing applications a waste gate would be a waste of time.
     
  10. Frosty

    Frosty Previous Member

    Why so long for a reply ?--are you googling?
     
  11. StianM
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    StianM Senior Member

    [​IMG][​IMG]

    I don't think those Volvos last 10 years eather. A waste gate would be a waste if you use it for tractor pulling, but would be bether if you want to have a larger range off operation on the turbo.
     
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  12. StianM
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    StianM Senior Member

    The only draving I have off a sequensial system is in a old book I have about turbocharging gasoline engines so I neaded to seartch, but I did not use google;)
     
  13. lazeyjack

    lazeyjack Guest

    googling ? **** I spent my life with diesels
    turbos are not jus for hp, sometimes jus to quieten the exhaust
    clean the exhaust
    been around since the 50,s
    you can put the biggest T on a motor, won't do ZILCH less you have the breathing cap. the fuel,
    engine builders in tiny engines like volvo,have hand grenade ratings, just to sell their product, serious builders rate their engines sensibly, take your pick
     
  14. Frosty

    Frosty Previous Member

    Stan None of the pictures (nice pics ) are of sequential charging though.

    For instance if one of those chargers blew out you would still get charging from the other.

    I assume that it is a circuit drawing of the real motor.
     

  15. StianM
    Joined: May 2006
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    StianM Senior Member

    Turbos is for more than that. Turbos lower the exhaust gas temperature since more air/g fuel is used and is increased more if a intercooler is aplied.

    A turbo increase the mass off air in the cylinder creating conditions for a behter combustion. I think the B&W two-strokes use 4 bar now to make shure they can burn all the HFO.

    Your right the turbo silence the exhaust.

    A turbo is a all ower good investment on the diesel and gues that is why we had it for so manny years. I think sulzer used forced induction on there marine engines in the 30's, but I think it was mecanical.

    I think your confusing with a twin turbo setup and a sequensial. They work the same, but a sequensial only runn 1 turbo online at all times. The second one is only engaged when more airflow is required. It's a system that brings more bost earlier and almoust without lag. I would not want one unless it was original or as a kit, it's almoust imposible to make it work properly.

    [​IMG]

    As you can read on the tecnical spesifications this is sequensial.
    Maybe you where thinking about two stage?
     
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