38mm wastegate suitable for 1.5 bar boost?

[GT_AUTO]

i dont really think its correct GT AUTO..
"Big Turbo/High Boost = Smaller Wastegate"

using a big turbo, high boost, cant use anything that is smaller than 40mm... it will spike to 1.8 br.. shite...

there,u said it urself.1.8bar.that's consider hi-boost.smaller w/gate can hold
higher boost cos of the diameter of the valve.if ur thinking of fooling around with
boost higher then 1.5,u should choose a smaller w/gate.40mm is still consider
small bro.what i mean big is 44mm n above.

 

[GT_AUTO]

hehe..bro i m running on 4G93T GSR..bro any advice?

advice?hehehe...none here:).just how much hp u expect from ur engine?what turbo r u using?

 

[vick85ong]

hehe..bro i m using td05h mod td06 front fin..if can wanna get around 300hp..hehe..can a bro?

 

[GT_AUTO]

sure....u can achieve ur goal easily.a lot of gsr with std td05 running
around with 300hp under the hood.

 

[kRiminaLz]

there,u said it urself.1.8bar.that's consider hi-boost.smaller w/gate can hold
higher boost cos of the diameter of the valve.if ur thinking of fooling around with
boost higher then 1.5,u should choose a smaller w/gate.40mm is still consider
small bro.what i mean big is 44mm n above.

anything that is B]
40 n above is considered big..
im using a 44....

 

[GT_AUTO]

anything that is B]
40 n above is considered big..
im using a 44....

below 38?there's only 1 more option n that is 35mm.usually 35 is
more suitable for k-car cos it to small.for me,38 n 40mm is considered
small n anything above that size is big.in our market there's several size
to choose from.35,38,40,41,44,46,50 n 60mm.by the mention size,u can
see for urself which 1 is consider small,medium n big.
that just my opinion lar kriminalz..

 

[DDgreystar]

m i rite to say in order to achieve higher boost n whp (based on stock evo td05-16g).....bigger wastegate should be better ??....some evos using .38........some on .44 .........hmmm

 

[GT_AUTO]

the bigger the valve,the easier the exhaust gas escape.u do the math.:)

 

[kRiminaLz]

"Big Turbo/High Boost = big wastegate

small wastegate (doesnt matter if its 0.7 or 1br spring) will choke for this kind of application, resulting a boost spike.. try to d.i.y n see the result...
***high boosting

this can only be overcome if let say (example)............ if ur using a 20g turbo boosting at 1.4 - 1.5br with a 38mm wastegate, u need to port the turbo/exhaust housing so that it can releases the extra gases efficiently n to eliminate boost spike....

 

[GT_AUTO]

i'm also skeptical about this 6 years ago.i even disagreed with those
guys at tial.they use to preach about using small w/gate for hi boost
application.after turbosmart came out with the same conclusion
on choosing w/gate,i find that their statement make sense
(not saying that my theory r better then those w/gate maker).
think about it logically.:)

btw kriminalz,on ur second paragraph about porting the exhaust housing.
what does it got to do with w/gate???the w/gate is mount at the exhaust
manifold before the turbine housing.if the turbine housing is choking,that's
the design of the turbine that r flaw not the w/gate.:)

 

[kRiminaLz]

i'm also skeptical about this 6 years ago.i even disagreed with those

guys at tial.they use to preach about using small w/gate for hi boost
application.after turbosmart came out with the same conclusion
on choosing w/gate,i find that their statement make sense
(not saying that my theory r better then those w/gate maker).
think about it logically.:)

btw kriminalz,on ur second paragraph about porting the exhaust housing.
what does it got to do with w/gate???the w/gate is mount at the exhaust
manifold before the turbine housing.if the turbine housing is choking,that's
the design of the turbine that r flaw not the w/gate.:)

i dont really know how to actually explain this technically in sentences...
but this is proven..
there's this bloke few days back who just bought a big turbo (t04e if im not mistaken) uses a 38mm tial with 1br spring...
he sets his boost at 1.4 but the boost spike accordingly with his car's rpm, scary..
since that he is darn broke after spending, he opted to send it for modifying which costs a lil' bit lower than buying a new big wastegate...
after porting he's turbo (not sure which side, the inner or the outter part, n i believe this will add a bit" lag to the turbo) and also changed his wastepipe bigger, he manage to use back his 38mm tial...
now he's boosting happily at 1.4 without spike..

this ''Bloke" is somewhere in the forum, will ask him to reply hehehehe...
apologies if my sentence is a bit confusing

 

[GT_AUTO]

there's nothing wrong with ur sentence.i understand...:)

 

[renxun]

GT... try to imagine this.... take an example running 1.5bar with 38mm gate.
lets consider the 38 is small ....and it will spike to 1.8bar.. and i understand you trying to say that boost will only go higher if you use smaller gate.... hence if i presume that your boost that you want is actually 1.8bar, then your gate already start opening at 1.5bar and creep up to the 1.8bar.and that doesnt do any good too for your spool up...

an effective and efficient setup is ... gate fully close...assume you want to boost 1.5bar. it should be fully close untill 1.5bar and when the moment it open it will release all the xtra and hold your boost steady on 1.5bar. this means that your spool up time faster and hold your boost steady without spike. i would recomend to use biggest anyone can afford and play around with the spring and a proper boost controller. no harm having bigger gates. but never undersize a wastegate.

 

[DDgreystar]

renxun....i think your statement makes good sense although i been using dis kind of setup similarly

 

[GT_AUTO]

GT... try to imagine this.... take an example running 1.5bar with 38mm gate.
lets consider the 38 is small ....and it will spike to 1.8bar.. and i understand you trying to say that boost will only go higher if you use smaller gate.... hence if i presume that your boost that you want is actually 1.8bar, then your gate already start opening at 1.5bar and creep up to the 1.8bar.and that doesnt do any good too for your spool up...

an effective and efficient setup is ... gate fully close...assume you want to boost 1.5bar. it should be fully close untill 1.5bar and when the moment it open it will release all the xtra and hold your boost steady on 1.5bar. this means that your spool up time faster and hold your boost steady without spike. i would recomend to use biggest anyone can afford and play around with the spring and a proper boost controller. no harm having bigger gates. but never undersize a wastegate.

yes i understand ur statement rexun.what i'm trying to say is that small valve
hold hi boost better then the bigger 1.imagine the exhaust escape from the
bigger valve.the small valve will make the exhaust gases squeeze itself out from
a small hole hence higher boost.let say if ur looking at 1.8,of course we want
it to reach the targeted boost before the valve open.that not the issue here.
the issue is that the capability of a smaller valve to hold the boost higher
then the bigger valve.1 example is like today.i talk to a friend of mine who
own a 5++ hp drag satria.he's selling his 38mm tial w/gate n getting a bigger
1.i ask him why n he said that he's aiming for a lower boost at launch cos
the smaller valve tend to give higher boost.even tial n turbosmart recommend
this kind of set up.
"The more powerful the engine, the bigger the wastegate you need. This is one of the more popular misconceptions. Use this simple guide before setting out to find the biggest wastegate you can afford.
Big Turbo/Low Boost = Bigger Wastegate
Big Turbo/High Boost = Smaller Wastegate
Small Turbo/High Boost = Smaller Wastegate
Small Turbo/Low Boost = Bigger Wastegate"
-quote by turbosmart company.

or maybe this site can explain it better then me.:)
http://www.evans-tuning.com/tech11.html
and this site.
http://forums.performancecar.co.nz/phpBB/viewtopic.php?p=455903&sid=a901ed4ecca264afc5501659531eb0fa


btw,"it should be fully close untill 1.5bar and when the moment it open it will release all the xtra and hold your boost steady on 1.5bar"-this only work if u
have gated or electronic boost ctrl.it will hold the boost n let it go once the
targeted boost is reach.

 

[renxun]

thats is wat im trying to say ... smaller wastegate will NOT hold high boost steady. im running on a gt3540 and its consider big for the normal street cars out there. running 1.7bar on hi-boost mode and 1.4bar low boost. using 38mm gate will not be able to hold my boost steady at all.it will continue spiking up as my rpm goes higher. hence my 1.4bar become 1.6-1.65 and my 1.7 will be somewhere close to 2bar. and where is the point that it can hold? if around 2bar is what i want then its already creep at 1.7. and if i set my rev limit to 9000rpm the boost will even climb higher. it doesnt hold my friend. its not a lot of misconception out side pl have. an internet write up is still a write up. they can write anything they want. you can find out your own answer by xperimenting if you have a big turbo and your engine is safe to run hi boost (above 1.5bar)

and holding boost is actually not 2 differant things with the spike and creep issue with smaller wastegate.what your friend is telling you in his satria is his wastegate tend to give higher boost because the wastegate will spike and he want to change bigger gate to eliminate this issue...bcuz it CANT hold the boost it had been set.ie. 1.5bar set value spike to 1.8bar. hence bigger gate to hold 1.5bar.for him he say lower down the boost.some pl xplain and they knw wat they mean however might not be clear on verbal and also there might be misunderstand on his meaning on your side.

i hope this can clear lots of doubt. u mayb still unable to catch wat im trying to say as xplaination in words also 'might' lead to misunderstanding. however im trying to my best to xplain it here. this had not been an issue all this while as long as im concern most street cars on the road are runnig 1.2bar and below and turbine size not bigger then a td05.some old school might use up to ct26 size type.hence using a good tial 38mm is not an issue.

but when it goes beyond the level... ie... my car..or any car which are street drag, drag car.....somewhere between 45-60 is used depends on affordability and need.i dont have 500++ whp but i have somewhere near that 500whp figure with high octane fuel on my 1jz. a 2000cc satria fully make up will have to run around 1.7-2bar of boost with at least a gt3037 and above to hit 500whp and not to forget boosted fuel too...hence the need of bigger wastegate

**might sound like a personal attack to gt but pls dont feel so. me not intended to do so.hoping this can be a constructive discusssion

 

[GT_AUTO]

no lar bro.is a forum mar.we discuss thing here.it's ok what.at least i can
hear other ppl's opinion on the w/gate thingy.

btw,gt3540 is big for a street use car.u can achieve better then 500whp.

 

[renxun]

tak dapat la.. dyno mati mati also somewhere near 500 only ..i cant go higher then 1.7 as my injectors are maxing out at 85% duty cycle. and i cant afford larger injectors . furthermore im afraid my intercoolers,piping connection and fuel pumps unable to deliver because the bosch fuel pump im using is only capable of 73psi max.. and its already near that region at 1.7bar. worst thing is its still stock internals except for the head area.and afraid my clutch might fail to grip if i go beyond the hp....

conclusion is it will be another major upgrade or major jump if i were to go further increase the horsepower that im having..the only way i can up my hp the easiest way is to use high octane fuel and add some timing while maintain the current boost

 

[GT_AUTO]

1 of my friend is also using gt3540 but on a drag car.573whp.but he's experience
the same problem as ur's.the inj duty cycle is nearly max out.right now he's
changing the injector to 1000cc.after this,maybe he can reach 600whp.

 

[renxun]

for me i guess thats where i stop upgrading.. will cost too much for the next level... almost everything need to re-do....anyway my car is not drag car... its quite fast already for street usage and now my younger bro is using my car to work since tis is his first job and cant afford a car yet... =P