Turbo Misconceptions

jinkl

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Would like to clear some big misconceptions , received too many PM's regarding this
sifu sifu , sdf , bebolasgalas can add more if got anymore info


1. A/R of turbo
Bigger A/R does not mean bigger turbo. AR80 is not bigger turbo than AR70 or AR60.
Must understand what is A/R first. A/R is just a ratio that garrett uses for their housing.

compressor_housing_showing.gif


some pics of compressor housings

the T04E family housings
T04E60507060.jpg


T04b/e/s
T04housings.jpg


AR80 t25 turbo
S5000185-1.jpg


AR60 t28 turbo
Turbos008.jpg


so how now guys, the AR80 is bigger than the AR70 ? hehehhe
and dont compare a ar70 with another ar70 turbo , u need a full spec to compare the turbos

a GT35R , GT40R , T04R , all uses same front compressor housing, A/R 70 , so u cant really tell that both cars are using AR70 so they have the same power output , a GT40R and GT35R have a diffrent hp range and so does the T04R and etc.

turbos.JPG

this is T70 vs GT40 vs GT42


hehe thank u , :P , too bored to reply all the PM's which states "I have a fren selling AR70 turbo" , "I want to buy AR70 turbo, ok ah?" etc

So guys , a bigger A/R doesnt determine a bigger turbo
 
yeah,,,thx for the write up jin. me too, many of my friends confused about the A/R hence they this big A/R means big turbo...haizz. sometimes i feel not in the mood to straighten up their confusion after many times already tell the same thing over the time
 
just wanna add up..here the plot goes..and this is a real story..

when : last eidulfitri raya
where : kelantan
actors : 1 black satria vs bunch of other turbo's
story : the satria beats all of its nemesis..some of them equipped with GT35 and TO4R and etc..and the best of it is that..rumours say that the satria only use AR 50..and guess what ITS TRUE..
 
so what's the meaning of this ? A/R 50 is what turbo ? that's the most important question


p/s : 1 more thing, in drag race, horsepower won't guarantee a victory. that's why in some cases vtec car with only 200whp ++ can beat 400whp turbo car
 
just wanna add up..here the plot goes..and this is a real story..

when : last eidulfitri raya
where : kelantan
actors : 1 black satria vs bunch of other turbo's
story : the satria beats all of its nemesis..some of them equipped with GT35 and TO4R and etc..and the best of it is that..rumours say that the satria only use AR 50..and guess what ITS TRUE..

black satria JDT ker??:stupid::listen:
 
the one that charges the battery :P

Bump: putra4G63 , dont get ur story, so meaning ? err

Sorry bro jinkl for 'kacau' your thread..This is a very informative thread..I know my post is out of topic a little bit..what i mean to say is that, people keep on asking about AR 50,60 or 70..What is more important is to get the turbo which suits your engine capacity best..A friend of mine explain to me few times already about this AR but to be honest, even until now i dont really understand it..the same does not go for everyone,maybe it's just me(a little bit of lag in learning)..there are too many things to learn, thats why i dont ask about AR anymore although GT35 AR 70 will do wonders to my car..hehehe..
Having said that, i hope that this thread by bro jinkl has settled the misconception once and for all..

..My apologize again...With Regards..
 
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simple explanation from Garrett on their method called A/R.

whereas IHI, MHI, Holset and Borg Warner measure differently, hence they measure the smallest volute in the housing area and it's usually in "cm". Eg. IHI has P12 = 12cm2 and MHI has a 6 or 8 on the turbine housing it depicts 6cm or 8cm volute area.

Holset doesn't measure the trim of a compressor wheel, instead they only look at the width of a compressor wheel, hence the comparison vs a Garrett style (in2 / ex2 x 100 = trim) vs Borgwarner vs IHI vs MHI measurement isn't really fair and the only way is via the manufacturer compressor map chart. (again this is only a guide, if it's been mix-n-matched / hybrid, the compressor map may not be accurate anymore and if the displacement of engine is different, the outcome is gonna be varied as well). Japanese makers are very seclusive and compressor maps are never easy to get, even distributors find it a hassle to obtain one.

Turbine wheel trim is variable as well and old skool style of Garrett (o-trim, p-trim, q-trim) are no longer relevant. IHI has a mixed flow trim. Then came cut backs and now Garrett has GT trims. So too many to compare and explain.

Products these days work out straight out of the box ! Don't bother with old skool tech of mix-n-match and hybrids, buy a part number and plonk it right in your engine, it'll deliver the HP closest to your desire. As an end user like us all, we just want something that works, unless you have lotsa time and money to R&D.

I am glad jin started this thread and hopefully it gets logged and noticed and more importantly it clear up the air over "myths". These explanations and discussion have been around for a long long time in ZTH especially.

Guys, keep it coming BUT keep it constructive.
 

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sdf , can u plz recommend me the best turbine for my evo4 engine? i want lots of torque, my last dyno only manage 382nm of torque, and my budget not much also, around 2k is ok, unless u will trade in my td05hr....and im planning on only putting e-manage, 1.8mm gasket, walbro and higher cc injectors, and maybe banana....
 
sdf , can u plz recommend me the best turbine for my evo4 engine? i want lots of torque, my last dyno only manage 382nm of torque, and my budget not much also, around 2k is ok, unless u will trade in my td05hr....and im planning on only putting e-manage, 1.8mm gasket, walbro and higher cc injectors, and maybe banana....

for 2k, even after trade in n topup, it wont fetch into the gt30 price range
but a t3/t4 is in the range , t04e should be fine in the 350hp+ range
but do remember that u need a banana , cheap ones are 700-800 , good ones are 1200-1400
i tink SDF can also go 20g for ya , ask em n see
 
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jin, i wanted to just shroud the housing and plunk in 20g, but i cant leave my car in the workshop more then 2 days because i use my car for work daily haha....u coming down to mell shop tonite?
 
lotsa torque and great drivability would be the GT3037R with a 0.63t/h.

Then again..2K won't get you there mate.

BTW - jin started this thread as a preconception to misconception on turbo understandings..as for pricing and enquiries, it's better done in private. Thanx.
 
it's clear the muddy water....hope our zth forumers will read this...
 
so what's the meaning of this ? A/R 50 is what turbo ? that's the most important question


p/s : 1 more thing, in drag race, horsepower won't guarantee a victory. that's why in some cases vtec car with only 200whp ++ can beat 400whp turbo car

Why? Please explain? How come 400whp cannot win 200whp?
 
Why? Please explain? How come 400whp cannot win 200whp?

because there are many other factors that come into play in a race for example torque, traction, driver's shifting skills, etc etc.....
Mostly below 300m drag 20B vtec with some mod and slight moded MMC turbo either one of them can win one.Reason is that vtec got good 1st,2nd,3rdgear ratios...MMC standard lock 4wd gearbox is suck.it all depends onlaunching time.Thats why vtec car love to drag with turbo for 250-300m lol.However,if drag for 400m is another difference stories.:biggrin:
 
Mostly below 300m drag 20B vtec with some mod and slight moded MMC turbo either one of them can win one.Reason is that vtec got good 1st,2nd,3rdgear ratios...MMC standard lock 4wd gearbox is suck.it all depends onlaunching time.Thats why vtec car love to drag with turbo for 250-300m lol.However,if drag for 400m is another difference stories.:biggrin:

yess!!!! coz after 300m and the turbo is spooling like crazy :biggrin:
the vtec will probably be behind
 
yeap...63t at 3rd to 4th gear will go like hell.This is bcoz the spool n the ratio match n the traction will stick to the tarmac.IMHO,the best final drive is from e1 n vr4rs.
 
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