Page 6 of 8 FirstFirst ... 45678 LastLast
Results 76 to 90 of 110

Thread: Turbo performance?

  1. #76
    Join Date
    6th December 2003 - 15:22
    Bike
    2001 Duc 7 4 8 R
    Location
    Capital
    Posts
    520
    To turbo timer or not comes down to the use of the vechile. If your running a standard boost and you've allowed turbo to spool down then you dont need one. If your running extra boost or using for comp. use then a minute or two gives the housing and manifold a chance to drop below the point of cooking up the remaining oil from the oil feed. It takes a while for it to return via the drain feed back into your sump. I'll be running one on my club car for this reason

    Check out this vid , and think about how long the manifold is taking to drop down from being red hot.

    http://www.youtube.com/watch?v=Yfom9...ture=endscreen
    It's not a beer pot .... It's a fuel tank for a sex machine

    Trip of a life time http://www.buenosaires-caracas.com.ar/tours.html
    Trip details here

  2. #77
    Join Date
    10th December 2005 - 15:33
    Bike
    77' CB750 Cafe Racer, 2009 Z750
    Location
    Majorka'
    Posts
    1,395
    Quote Originally Posted by onearmedbandit View Post
    I've never seen a turbo glow 'cherry red hot' under normal use, including thrashing the nuts off turbo cars. And if they were so critical, how come virtually no turbo cars from factory come with them?
    I'm guessing because In a lot of places its illegal to leave a car running unatended not to mention safety issues if the car was left in a locked garage. Your car your turbo your money, if you look on all the turbo repairers and manufacturers websites they all mention the dangers of hot shutdowns. Its not that hard to get a dull cherry red glow on an unturboed engine, how often have you looked at night?
    I love the smell of twin V16's in the morning..

  3. #78
    Join Date
    10th December 2005 - 15:33
    Bike
    77' CB750 Cafe Racer, 2009 Z750
    Location
    Majorka'
    Posts
    1,395
    Quote Originally Posted by ducatilover View Post
    How often are people running the turbo in their Evo/etc that hot?
    I still think there is no advantage running the engine on for 1-3min to "cool" the oil. It's not going to cool much and it's still pumping hot oil to the turbo.

    I can understand if you're getting the turbo red hot just before stopping (shouldn't really be an issue on the road...) as that's an extreme.
    But, otherwise letting your engine idle is not really helping anything.

    In my opinion.
    Not sure what your saying, the oil is cooling the turbo bearings the oil won't get cooler it will get hotter taking heat away from the turbo.
    I love the smell of twin V16's in the morning..

  4. #79
    Join Date
    16th September 2004 - 16:48
    Bike
    PopTart Katoona
    Location
    CT, USA
    Posts
    6,542
    Blog Entries
    1
    Quote Originally Posted by FJRider View Post
    Most diesel manufacturers reccommend an idle-down period before shutdown.
    Actually anything with 2 foot throw on a piston recommends "idle-down" times.
    Hell its even on the old David Brown 885.

    I can answer the "why is not factory ttimer?" question. There is on 'few' cars. But there has to be a need for it. And most only have about 2-5 seconds........not the bad old 1-2 minutes.
    Not to mention that the turbo's of today from what they were in the 80's. I felt like a complete noob recently when I found out a TD04/05 Hybrid has nothing on the new standard turbos.
    Reactor Online. Sensors Online. Weapons Online. All Systems Nominal.

  5. #80
    Join Date
    16th September 2004 - 16:48
    Bike
    PopTart Katoona
    Location
    CT, USA
    Posts
    6,542
    Blog Entries
    1
    Quote Originally Posted by jonbuoy View Post
    I'm guessing because In a lot of places its illegal to leave a car running unatended not to mention safety issues if the car was left in a locked garage. Your car your turbo your money, if you look on all the turbo repairers and manufacturers websites they all mention the dangers of hot shutdowns. Its not that hard to get a dull cherry red glow on an unturboed engine, how often have you looked at night?
    Yeah/Nah.......sometimes its good and sometimes its crap advice.

    As mentioned earlier - sometimes a new 'hot fix update' comes out for a vehicle............I suspect if Mitsubishi blew up a decent amount of turbos, factory fitted turbo timers would be high on their list.
    Instead it seems that a carbon fibre roof is more important

    I actually think they should be factory fitted (on all vehicles), but then again I am an engineer who dreams of utopia and never gets the budget.
    Reactor Online. Sensors Online. Weapons Online. All Systems Nominal.

  6. #81
    Join Date
    10th December 2005 - 15:33
    Bike
    77' CB750 Cafe Racer, 2009 Z750
    Location
    Majorka'
    Posts
    1,395
    Timers are illegal here even so I would probably just go with an egt gauge. Lets face it car manufacturers arent interested in long term reliability of your car, after 7 years they want you to buy a new one.
    I love the smell of twin V16's in the morning..

  7. #82
    Join Date
    17th July 2005 - 22:28
    Bike
    Dougcati, Geoff and Suzi
    Location
    Banjo town
    Posts
    10,162
    Quote Originally Posted by jonbuoy View Post
    Not sure what your saying, the oil is cooling the turbo bearings the oil won't get cooler it will get hotter taking heat away from the turbo.
    Was typing too fast for my d\slow brain methinks. (Happens a lot, I own a Kawasaki)
    The oil in the turbo is getting as hot, if not hotter than the block.
    So how is a turbo timer going to help that? Agreed, in extreme situations, it may help, but why do you need a turbo timer at the track? No-one is stealing your car and the time the engine spends at idle is more important than your turbo cooling isn't it? You have far lower oil pressure at idle, the turbo is only heating the oil if it's red hot unless you idle your engine for a significant amount of time (Loner than 1-3min).

    So, why bother? Your turbo is going to be hotter than the block temp, regardless, so it's only heating the oil. In a road application.

    (Disclaimer; In my opinion.)

    I have seen many vehicles with turbo timers have "early" turbo failure, as well with vehicles without. I personally think it comes down to the design of the turbo, for example, a lower friction shaft will last well, whereas an older design with solid bearings will not last as well. Same goes for a turbo set up with a decent wastegate and blowoff valve, without the compressor stall/surge you'll have a much happier turbo.
    Quote Originally Posted by Paul in NZ View Post
    Ha...Thats true but life is full horrible choices sometimes Merv. Then sometimes just plain stuff happens... and then some more stuff happens.....




    Alloy, stainless and Ti polishing.
    Bling your bike out!
    PM me

  8. #83
    Join Date
    17th July 2005 - 22:28
    Bike
    Dougcati, Geoff and Suzi
    Location
    Banjo town
    Posts
    10,162
    Quote Originally Posted by avgas View Post
    Instead it seems that a carbon fibre roof is more important
    Have you seen how many roofs on 90's Mitsis rust? CM/CD5A etc etc etc all pull the spot welds int he roof because the glue in them is shiiiiiiiiiite? I think they should have looked at that long before turbo problems...
    Quote Originally Posted by Paul in NZ View Post
    Ha...Thats true but life is full horrible choices sometimes Merv. Then sometimes just plain stuff happens... and then some more stuff happens.....




    Alloy, stainless and Ti polishing.
    Bling your bike out!
    PM me

  9. #84
    Join Date
    10th December 2005 - 15:33
    Bike
    77' CB750 Cafe Racer, 2009 Z750
    Location
    Majorka'
    Posts
    1,395
    Quote Originally Posted by ducatilover View Post
    Was typing too fast for my d\slow brain methinks. (Happens a lot, I own a Kawasaki)
    The oil in the turbo is getting as hot, if not hotter than the block.
    So how is a turbo timer going to help that? Agreed, in extreme situations, it may help, but why do you need a turbo timer at the track? No-one is stealing your car and the time the engine spends at idle is more important than your turbo cooling isn't it? You have far lower oil pressure at idle, the turbo is only heating the oil if it's red hot unless you idle your engine for a significant amount of time (Loner than 1-3min).

    So, why bother? Your turbo is going to be hotter than the block temp, regardless, so it's only heating the oil. In a road application.

    (Disclaimer; In my opinion.)

    I have seen many vehicles with turbo timers have "early" turbo failure, as well with vehicles without. I personally think it comes down to the design of the turbo, for example, a lower friction shaft will last well, whereas an older design with solid bearings will not last as well. Same goes for a turbo set up with a decent wastegate and blowoff valve, without the compressor stall/surge you'll have a much happier turbo.
    No I'm still not getting it, if the turbo is hotter than the oil that flows through the bearings (which it will be if its got 400 degree gasses passing through) the turbo will be cooled by the oil. As long as there is oil flowing what has the pressure got to do with it? Even at idle your exhaust gets pretty toasty, I can put my hand on the engine block after a hard run for a few seconds, I wouldn't try touching a turbo or exhaust manifold. So yeah the block, cooling water and oil will soak up the heat from the hotter turbo. You dont think passing oil through it can cool it?
    I love the smell of twin V16's in the morning..

  10. #85
    Join Date
    4th November 2003 - 13:00
    Bike
    BSA A10
    Location
    Rangiora
    Posts
    12,711
    Quote Originally Posted by avgas View Post
    ..I suspect if Mitsubishi blew up a decent amount of turbos, factory fitted turbo timers would be high on their list..
    The Mitusubishi Tredia/Cordia had a window sticker advising to let it idle for a minute or two before shutting down or it could cause turbo "problems"
    "If you can make black marks on a straight from the time you turn out of a corner until the braking point of the next turn, then you have enough power."


    Quote Originally Posted by scracha View Post
    Even BP would shy away from cleaning up a sidecar oil spill.
    Quote Originally Posted by Warren Zevon
    Send Lawyers, guns and money, the shit has hit the fan

  11. #86
    Join Date
    17th July 2005 - 22:28
    Bike
    Dougcati, Geoff and Suzi
    Location
    Banjo town
    Posts
    10,162
    Quote Originally Posted by jonbuoy View Post
    No I'm still not getting it, if the turbo is hotter than the oil that flows through the bearings (which it will be if its got 400 degree gasses passing through) the turbo will be cooled by the oil. As long as there is oil flowing what has the pressure got to do with it? Even at idle your exhaust gets pretty toasty, I can put my hand on the engine block after a hard run for a few seconds, I wouldn't try touching a turbo or exhaust manifold. So yeah the block, cooling water and oil will soak up the heat from the hotter turbo. You dont think passing oil through it can cool it?
    I just don't think it's making a huge difference if you idle it for 1-3min, that's not exactly a long period of time and the turbo is still accumulating heat during idle. As OAB said, why were there not more fitted from factory?

    I could be completely wrong though, highly possible
    Quote Originally Posted by Paul in NZ View Post
    Ha...Thats true but life is full horrible choices sometimes Merv. Then sometimes just plain stuff happens... and then some more stuff happens.....




    Alloy, stainless and Ti polishing.
    Bling your bike out!
    PM me

  12. #87
    Join Date
    3rd February 2004 - 08:11
    Bike
    1982 Suzuki GS1100GK, 2008 KLR650
    Location
    Wallaceville, Upper hutt
    Posts
    5,049
    Blog Entries
    4
    Quote Originally Posted by ducatilover View Post
    I have seen many vehicles with turbo timers have "early" turbo failure, as well with vehicles without. I personally think it comes down to the design of the turbo, for example, a lower friction shaft will last well, whereas an older design with solid bearings will not last as well. Same goes for a turbo set up with a decent wastegate and blowoff valve, without the compressor stall/surge you'll have a much happier turbo.
    Most of my turbo experience was Cat earthmovers, but these ALL used floating bush type bearings (ie what you describe as solid bearings) - the oil film seperates the shaft from the bushing (bearing), AND the bushing from the housing. These turbos had uptimes of thousands of hours, most of which was under full load, red hot exhast housing conditions. The turbo was correctly sized at the factory (not much aftermarket hotrod stuff for D8s ), no wastegate or blowoff, and provided they were fed a steady diet of clean oil and clean air would last more or less indefinitly. An extended (15 minute or more ) pre-shutdown idle was mandatory.

    This book http://www.amazon.com/Turbochargers-.../dp/0912656492 gives a LOT of good info (MacInnes designed a lot of the Rajay turbos)and the engine pictured on the cover is niiice
    it's not a bad thing till you throw a KLR into the mix.
    those cheap ass bitches can do anything with ductape.
    (PostalDave on ADVrider)

  13. #88
    Join Date
    17th July 2005 - 22:28
    Bike
    Dougcati, Geoff and Suzi
    Location
    Banjo town
    Posts
    10,162
    Quote Originally Posted by pete376403 View Post
    Most of my turbo experience was Cat earthmovers, but these ALL used floating bush type bearings (ie what you describe as solid bearings) - the oil film seperates the shaft from the bushing (bearing), AND the bushing from the housing. These turbos had uptimes of thousands of hours, most of which was under full load, red hot exhast housing conditions. The turbo was correctly sized at the factory (not much aftermarket hotrod stuff for D8s ), no wastegate or blowoff, and provided they were fed a steady diet of clean oil and clean air would last more or less indefinitly. An extended (15 minute or more ) pre-shutdown idle was mandatory.

    This book http://www.amazon.com/Turbochargers-.../dp/0912656492 gives a LOT of good info (MacInnes designed a lot of the Rajay turbos)and the engine pictured on the cover is niiice
    Very good info, thanks
    Quote Originally Posted by Paul in NZ View Post
    Ha...Thats true but life is full horrible choices sometimes Merv. Then sometimes just plain stuff happens... and then some more stuff happens.....




    Alloy, stainless and Ti polishing.
    Bling your bike out!
    PM me

  14. #89
    Join Date
    12th July 2003 - 01:10
    Bike
    Royal Enfield 650 & a V8 or two..
    Location
    The Riviera of the South
    Posts
    14,068
    Quote Originally Posted by ducatilover View Post
    I just don't think it's making a huge difference if you idle it for 1-3min, that's not exactly a long period of time and the turbo is still accumulating heat during idle.
    My take of this is: the turbo is NOT 'accumulating' heat during idle to the extent it did during a high-load fang, it would only be as hot as a regular exhaust manifold if just left at idle - but during the high-load fang it creates heat, lots of it after that the temp drops as the load drops.

    The oil flowing through the turbo while the motor is idling (whether with a timer or otherwise) will keep the bearings lubed as (I may be wrong - again!) shutting down after 'giving it heaps' the oil-pressure drops to zilch - but the turbo-shaft will still be spinning a bit.

    And a steady flow of oil through the turbo will cool it as the oil will be way cooler than the turbo housing.
    Winding up drongos, foil hat wearers and over sensitive KBers for over 14,000 posts...........
    " Life is not a rehearsal, it's as happy or miserable as you want to make it"

  15. #90
    Join Date
    17th February 2005 - 11:36
    Bike
    Bikes!
    Location
    Christchurch
    Posts
    9,651
    Quote Originally Posted by schrodingers cat View Post
    The problem is the heat soak 'burning' the oil and causing carbon buildup which reduces the clearances. Something spinning at thses speeds needs to be pretty right. Too much build up leads to reduced lubrication and then some riding on the bus.
    And here was me thinking we'd go the entire thread without hearing from somebody who knows.

    The OEM doesn't fit them because most people never run them WOT then switch them off straight away... and they tell you not to do that in the handbook. As a result, it's cheaper to replace the odd turbo than it is the equip every car with one. Every manufacturer has entire departments dedicated to calculating risks like that, and those people get just as much say as the engineers.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •