Wastegate Explained.

SDF

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SDF

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Wastegates - Facts and Fiction


With so many contradicting opinions and recommendations, it’s a little wonder choosing the right Wastegate for your application can be a confusing.
We try to disspell some myths and shed some light on the most common misconceptions regarding wastegates.


TRUE OR FALSE
*The more powerful the engine, the bigger the
wastegate you need.*
False. This is one of the more popular misconceptions. A wastegate is possibly the only component in your whole engine package that can actually be made smaller as you increase your boost/horsepower output. Use this simple guide:
Big Turbo/Low Boost = Bigger Wastegate
Big Turbo/High Boost = Smaller Wastegate
Small Turbo/High Boost = Smaller Wastegate
Small Turbo/Low Boost = Bigger Wastegate

Wastegates don’t operate in high temperatures.
False. Contrary to the popular belief, external wastegates are usually mounted at the hottest part of the exhaust. It’s the place where all the exhaust gases meet, creating extra heat. This, combined with the late combustion of unburnt fuel (due to rich mixtures, retarded timing and high octane fuels) significantly raises the exhaust temperature.


Larger wastegate valve diameter = better flow.
True – sort of. While the valve diameter is without a doubt an important part of the flow rate, equally important, but often misunderstood, is the importance of the flow path. When comparing wastegates with similar valve size, it is important to have a balanced body/valve/spring combination that is designed to work together to allow for maximum boost control. All Turbosmart wastegates are designed with this in mind.


(*article courtesy of Turbosmart) :smokin:
 

renxun

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renxun

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But.... do enlight me if im wrong... i guess there will be other factor for my situation too...

my 50mm and my 44mm trust unable to regulate and give me a stable boost building and boost hold when i set my boost anything above 1.5bar...it will creep

my 50mm turbosmart progate 50mm... can give me very good boost control even at above 1.5bar... no creeping

could it be matter of design? or the fact of the reasoning of big , small wastegate?
 

NFS

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NFS

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shudn't high or low boost depends on the turbo size ...

that's what i thought ...
 

speed2horizon

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speed2horizon

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Aiyo.....
T.T

Turbo size determines how high u want to boost... But now ppl are asking at what boost level begins to consider high boost.

Back to ur question. maximum efficient boost depends on the turbo size. Boost depends on wastegate or actuator. I can have a big turbine, but using tial 38mm external wastegate with 0.4bar spring. I'll still boost at 0.4 bars....
 

SKYBLUEV6

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SKYBLUEV6

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if 1 bar spring so i can stand to 1 bar boost?

Bump: if 1 bar spring so i can stand to 1 bar boost?
 

rakesh_v6

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rakesh_v6

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im using TDO5,changed my cam to HKS standard degree and crankshaft HKS attached with haltech ecu..boosting at 1.2 bar...does it make sense sifus

need advice
 

SDF

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SDF

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rakesh..wrong thread to ask and the what is the question ? it doesn't tie in.

this thread is about Wastegates.
 

SDF

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SDF

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lowest boost = 7psi (0.5bar)
highest boost = 28psi (2bar) without boost controller

If you run an electronic boost controller.. the wastegate will alter according to the preset level.
 

r_monstar

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r_monstar

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thanks, now i can sleep better. knowing the car can boost..heehehe...(before this max at 1.5 bar, old w/gate and old ext.manifold)
 

blitz3r

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blitz3r

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hey guys... i nd some help... i recently brought my car 2 a workshop 4 a check n he told me my waste closes 2 slow n late... so i cant get a high boost... wat can i do 2 decrese d time of d waste gate opening n closing bside changing d whole unit....
im using an implanted 2jz... stock turbos...
realli nd help...thx... stil a newbie=p
 

SDF

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SDF

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blitzer..more info on your turbo and your wastegate / actuator please.
What boost you running now and what boost you intend to run it to ?
what boost controller you have now ?

Bump: blitzer..more info on your turbo and your wastegate / actuator please.
What boost you running now and what boost you intend to run it to ?
what boost controller you have now ?
 

turbolover

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turbolover

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Hey guys.hope u can help me explain this.having a stock GSR engine with a GSR RS chip.All running stock.I am thinking of mating a 44mm wastegate(which i already have).will this be ok?i keep hearing about the wastegate spring.do i need to do any modification since i'm running stock?

Bump: Hey guys.hope u can help me explain this.having a stock GSR engine with a GSR RS chip.All running stock.I am thinking of mating a 44mm wastegate(which i already have).will this be ok?i keep hearing about the wastegate spring.do i need to do any modification since i'm running stock?
 

speed2horizon

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speed2horizon

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Hey guys.hope u can help me explain this.having a stock GSR engine with a GSR RS chip.All running stock.I am thinking of mating a 44mm wastegate(which i already have).will this be ok?i keep hearing about the wastegate spring.do i need to do any modification since i'm running stock?

Bump: Hey guys.hope u can help me explain this.having a stock GSR engine with a GSR RS chip.All running stock.I am thinking of mating a 44mm wastegate(which i already have).will this be ok?i keep hearing about the wastegate spring.do i need to do any modification since i'm running stock?
Well, 38mm or 44mm, it depends on the wastegate spring whether it opens at 0.7 bars, 1 bars or etc... When u have everything stock, GSR turbo boost at 0.7bars. So, if you have a wastegate with 0.7 bars spring rate, they should be the same. Wastegate has a better boost consistency compare to the stock internal actuator.

So, first thing u need to find out is the spring rate of your wastegate...