turbos don't BLOW UP...if it's genuine...
only NON GENUINE will blow up.
hmm , thts not the only cause rite
ceramic turbine wheel turbo boosted up cant break although its genuine ?
imbalanced compressor wheel can break the turbo ?
alien object sucked into turbo cant break the turbo ?
oil starvation cant break the turbo ?
modded heavy wheels on a thin shaft can break the turbo ?
a non performance 360 bearing put into trashing wont break the turbo although genuine ?
a even the ultimate garrett GT series boosted up high wont break the turbo ?
a genuine or not, depends on design too and its requirement, doesnt mean genuine its not gonna break. RB25's use GENUINE GARRETT mar, y not boost up to 2bar :D , genuine just means its designed and have passed through r&d and inspections. Their designs still have its limations, GENUINE is not BULLET PROOF , even the GT Garrett series has its downs n ups , in US, the DSM ppl have already moved away from the GT series , due to price where they can get a much more reliable & serviceable Holset & Borgwarner for even less than 1/2 the price of the GT with equivalent flow and spool.
depends wht turbo u r using, different turbo have different design failures
ceramic turbine fins tends to chip and crack off if boosted up
holset hx40 series have a smaller diameter shaft compared to the hx35 , there is where some ppl have faced broken shafts with the hx40's , some turbos require less oil , some more oil , some have pressure limits , some need feeds from oil pump, some need from the head , etc
BLOW UP = KAboom and not broken, which is why i said only NON GENUINE blows up.
And for your info : Genuine turbos go through a burst containment test, whereby IF pieces are broken it will not fly out through the compressor housing and turbine housing.
Have you seen a true containment test ?
As for the other parts you mentioned about 'breaking' a turbo..yes we all know if due to negligence and carelessness...a GENUINE turbo will break, but not BLOW UP aka Explode.
Don't tell me bout BorgWarner vs Holset vs Garrett mate..how many comparisons and consistent winning cars run them ? We have all these in stock. Question is, for daily driven versus Drag racing, the requirements are different, which is why certain guys in DSM forum try a Borg Warner -Air Werks or a Holset HX Racing.,why ?
Anything big flows more / alot..duh...which is why S400 or HX50 series can 'flow' an equivalent to a GT42 frame size.
Now..why is Garrett GT so popular worldwide, because of the smaller frame sizes (eg. GT25, GT28, GT30, GT32, GT35) able to spool up very much quicker over other makes and flowing more than a BorgWarner or Holset.
Now..another turbo fact for you.. The best small frames are in fact IHI and MHI, which is why they are mainly used on OEM engines and rarely sold as an aftermarket upgrade. They are lightweight and very durable.
So let's get this straight...my comment on GENUINE vs Non GENUINE is over the word = Blow Up aka Explode and not about it's durability.
according to compressor map
the highest flow is around 1.2bar , no point if u push it to 2bar , not efficient
According to my imagination of the map (extended to top-right of the graph), 1.2 bar is 72% efficiency (corrected air flow of about 30 lbs/min).
Whereas at pressure ratio of 3 (about 2 bar pressure) the efficiency would be about 68% (corrected air flow of nearly 35 lbs/min). I think my big intercooler can accept it in term of efficiency (as long as the turbo isn't blown up).
What we are discussing is the compressor side of the turbo. Anyway, which side will go first under harsh condition between compressor and turbine side? What I've heard, the turbine side will go first.
i wonder why pl like to hit high boost to achieve horsepower...? so much heat... went off efficiency curve....and a lot of stress and wear and tear to the turbo system....
i would rather wind down boost, premix methanol and wind up the timing instead.....it will still achieve what normal pl will achieve with a much higher boost and safer
Ok. That's my next target together with changing a new piggy back ECU.
But, methanol option will easily cost us around RM2k and don't forget for the consumable (mixture) afterward..! That's why some people are still left with the optimization of whatever they've already got.
an ultimate can switch between 2 injection maps and 2 ignition maps... which i tune one for petrol and another for methanol MIX.... not to say pure neat methanol...running pure methanol means you have to have another additional setup for you to switch with petrol and alot more complication...
methanol is just less than rm10 per litre... and you can mix from 10% up to 100% if you want provided you knw what you are doing. with a 20% mix i can make the same power im making at 2 bar boost at only 1.5bar. with the timing of 26degree at full boost... and you aint mixing the whole tank of petrol most of the time... maybe when you car had around 20litre left in the tank or less...
dont forget methanol mixture means running richer afr. i run around 10afr and that means an injector upgrade... i had 4units 510cc sub injector ready to spray if it needs additional consumption on top of my existing 6 units of 550cc...
on normal use my car is just like a cat purring at 1.5bar too .. but at much lower timing and conservative tune..
im still trying my best to lower my boost and my target is on 1.1bar.... it had its own advantage.it will make full boost very early and have a very wide usable power range to pull and lotsa torque and let you use a bigger rear turbine housing for extended top end....runs much cooler...lots of advantage with a reasonable low cost and low risk...
reason why pl blow (damage) their turbo is excessive boost.... running more than 2 bar on a small snail.... it cost excessive speed to the turbo and generate a lot of heat.... need not to elaborate much it will certainly heat your engine oil and if your engine oil overheats and cant do proper lubrication with proper operating pressure.... causing damage not only to turbo but to engine....
another thing is some car runs too high oil pressure to their turbo causing the seal to leak over the time.... it doesnt need to be a very powerfull pump to cause high oil pressure... it can be just as simple as using a wrong viscosity oil.
not proper cooling down of the car....if really whack hard and extreme.... no amount of turbo timer time can help u on the idle... bring your car for a normal drive off boost b4 you came to stop...
alot la... like running too small turbine housing could do damage too ... too long to be listed.. i guess better let bebola ganas sifu to elaborate more as he is specialize in this
Last edited by renxun; 10-27-2008 at 02:35 AM.
Reason: add info
I personnaly prefer water injection (or water mixed with methanol).
Refer to Hot Rod magazine, July 1983 page 59 "Water Injection" by Paul Stenquist says:-
HORSEPOWER IS MAINLY DEPENDENT ON CYLINDER PRESSURE ...
Nearly all of the changes that an enthusiast might attempt are designed to raise cylinder pressure: a higher compression ratio raises pressure by squeezing the mixture into a smaller combustion area; increasing spark advance raises cylinder pressure by giving the hot gases more time to expand; even valve timing and fuel system changes result a more cylinder pressure because they allow the cylinders to fill more completely.
Low octane fuel are incompatible with high cylinder pressure because ...
There are 3 ways to deal with detonation. You can (1) reduce cylinder pressure and sacrifice horsepower and efficiency, (2) buy expensive racing gasoline, or (3) inject water to control rising combustion chamber temperature - undoubtly the best.
Water injection can work for you in two different ways ... if it is injected properly and in the right amounts. A fully aerated water mist that mixes completely with the incoming charge can keep chamber temperature below the flash point of low-octane fuel until the point of spark ignition ...
On the other hand, a well distributed, fully aerated charge will turn into STEAM at the moment of combustion, EXPANDING NEARLY 1,700 TIMES. YOU'LL RECALL THAT HORSEPOWER IS PRIMARILY A FUNCTION OF CYLINDER PRESSURE ...
... in other word, a properly functioning water injection can provide both detonation control and increased horsepower.
Well, I have finally done my BOT and runned in. Now enjoying my ride... Touch wood, no coughing and no sneezing on my engine... Everything is fine boosting at 0.6-0.7 bars daily drive.
well, I've consulted one of my friend on the cooling system on the turbine.. One of my friend and I had an argument over a TD04L. Should it be oil cooled only or water and oil cooled... I insisted on water and oil cooled. And he keep saying that oil cool only is enough... and nobody oil + water cooled...
Well, I came from a mechanical engineering background and till now, I've been dealing with alot of machine built to produce heat... Well, I understand his message that says TD04L can be oil cooled only... But I couldn;t accept that he said no body water and oil cooled a TD04L and TD05... (Mitsu's OEM turbine)
If there is no purpose of having a double cooling system on a turbine, why the hell does Mitsu uses uncountable amount of effort and money in designing and producing a twin chamber cooling system.. I believe they don;t do things for no reason... And I also know that there are lotsa BOTs out there that only oil cooled the turbine... Can use I know can use.... But when say nobody uses water and oil cooled, I mean... i couldn;t accept lar...
however, this topic was brought to be compared with some of the garrett turbine that using oil cooled only.... Well, for me... It all depends on the initial designed cooling method... Well, Garrett using Oil cooled only because it's being designed to do this... So, the oil travelling chamber for cooling would be different from a water + oil cooled chambers... So, to my opinion, it's all about the design... Well, I know it's going to be a never ending argument if we continues... I ended the conversation with "nevermind lar... it's OK"
had a friend whom damaged his TD04L at 1 bar. Told me overheated and shaft bengkok. Send to Turbo Tong to repair cost alot, and finally got himself a TD04HL...
Met up with my cousin last week... Driving an Airtrek Turbo... Just upgraded to TD05. Wanted to sell his TD04L(Stock turbine) in very good condition. not even oil leaks and I asked him about his boost before upgraded to TD05. And I was suprised that he told me it's been 1.2 bars for 1 year + without giving any problem...
So... it immediately reminded me about the argument....
What do U think..?