1 Bar VS 1 Bar,whats the difference?

[Vboostec]

Jinkl...

Hoskos said... 1bar from td04 and td05 has a same pressure level but... the amount or mass of "air" volume is different. I 2nd this...

But hoskos....

U cant simply said 'not to throw unneccessary factor like compressor "flow" map'... this i'm not fully agreed with u. The flow map is the most important factor to determine turbo performance...

If u look at the turbobygarrett site... they shows us how to select a proper turbo for your application...

 

[xtremeleo]

I thought that was the topic of discussion and anyone cares may pose his/her opinion. Perhaps you can start turbo discussion on a new topic and let this one go on on its own? :regular_smile:

i didnt say dat nobody cant post anything, iam just pointing out dat u cant clarify anything when there r too much variables ie different turbine on different engine. u have to use sumthing dat can be a common factor and compare, i tot ive made dat clear in my previous post? i wasnt posting about preformance firgure, but how to compare CFM. u can only clarify dis only and if only u examine the turbines mentioned, on boost level mentioned on the same power supply unit ie engine.

how can u compare two different turbine on two different engine? dat doesnt make any sense.. or if its making sense to u, please explain as iam in deep confusion rite about now:_:

 

[xtremeleo]

Jinkl...
Hoskos said... 1bar from td04 and td05 has a same pressure level but... the amount or mass of "air" volume is different. I 2nd this...

i think its better if u post "amount or volume of air flowing through it per time is different" as if time isnt taken into consideration, any turbine can flow any amount of air past by it. rate is the keyword here

 

[Vboostec]

Heh heh...

So.. what is "amount/volume of air flowing through it per time is different" in rating or ratio? its lb/min rite? I know rate is the keyword here... mass/time.

Mitsu using CFM and garrett using lb/min

lb/min = 0.07 x CFM

I would like to put in as simple as I can... act

 

[lilvee]

For what ever reason, 1bar from td05 should produce more peak torque output than 1bar td04 from same engine.

 

[xtremeleo]

vboostec : dats a good explanation, bravo!!

lilvee : its becuase of the CFM difference, TD05 flows more in a certain time compared to a TD04, even at the same boost level. the thing is, where is its peak torque gonna be at?

 

[jinkl]

agreed
td04 and td05 1bar is 1bar , pressure is the same ,1 bar of pressure is one bar of pressure, bt the cfm that the turbo produce isnt the same, thats the reason u get better performance.
thats the confusion aight :)

 

[lilvee]

Nah... now a new topic already... more confussion.. heh heh

If u talking about where peak torque gonna be.. a load of thing need to be considered..

Actualy u can "tweak" (or maybe shift) your torque from a same turbo. Reducing back pressure at exhaust turbine one of them. This can be tweak by getting bigger A/R and trim sizzing. Sometime people call it "more lag", but actually u shift your peak torque to higher rpm. Your exh manifold sizzing also play a big role in this back pressure issues...

Many more variable can be "tweak"... Intercooler sizzing, charge pipe sizzing... and this excluded EMS tweaking... heh heh... fenin laa

vboostec : dats a good explanation, bravo!!

lilvee : its becuase of the CFM difference, TD05 flows more in a certain time compared to a TD04, even at the same boost level. the thing is, where is its peak torque gonna be at?

 

[lilvee]

And this was taken from Turbo Tech 101 Turbobygarrett site...

Mass Flow Rate

• Mass Flow Rate is the mass of air flowing through a compressor (and engine!) over a given period of time and is commonly expressed as lb/min (pounds per minute). Mass flow can be physically measured, but in many cases it is sufficient to estimate the mass flow for choosing the proper turbo.

• Many people use Volumetric Flow Rate (expressed in cubic feet per minute, CFM or ft3/min) instead of mass flow rate. Volumetric flow rate can be converted to mass flow by multiplying by the air density. Air density at sea level is 0.076lb/ft3

• What is my mass flow rate? As a very general rule, turbocharged gasoline engines will generate 9.5-10.5 horsepower (as measured at the flywheel) for each lb/min of airflow. So, an engine with a target peak horsepower of 400 Hp will require 36-44 lb/min of airflow to achieve that target. This is just a rough first approximation to help narrow the turbo selection options.

emm.... thanks vboostec for reminding me turbobygarrett site

 

[flamefox850]

And this was taken from Turbo Tech 101 Turbobygarrett site...

Mass Flow Rate

• Mass Flow Rate is the mass of air flowing through a compressor (and engine!) over a given period of time and is commonly expressed as lb/min (pounds per minute). Mass flow can be physically measured, but in many cases it is sufficient to estimate the mass flow for choosing the proper turbo.

• Many people use Volumetric Flow Rate (expressed in cubic feet per minute, CFM or ft3/min) instead of mass flow rate. Volumetric flow rate can be converted to mass flow by multiplying by the air density. Air density at sea level is 0.076lb/ft3

• What is my mass flow rate? As a very general rule, turbocharged gasoline engines will generate 9.5-10.5 horsepower (as measured at the flywheel) for each lb/min of airflow. So, an engine with a target peak horsepower of 400 Hp will require 36-44 lb/min of airflow to achieve that target. This is just a rough first approximation to help narrow the turbo selection options.

emm.... thanks vboostec for reminding me turbobygarrett site

waahh bro..so these r the best definitions.

many people also confuse between volume flow rate (cfm) and mass flow rate (lbs/min).

cfm doesn't count temperature but lbs/min does count the temp factor. so, lbs/min is a good number to look at when choosing a turbo.

so, the mass flow rated turbo already calculate using Ideal Gas Law formula for us la eh ? hehehe

 

[xtremeleo]

lilvee : dat was a good post

but as i mention, keeping a common factor(s) is important in comparing things such as flow rate, performance, of any items. iam sumone dat had been through several exhaust pipe an muffler selections (just to compare between pipe sizes, muffler types, etc), so i know the importance of back pressure, at least for my engine. iam now wit an apexi supermegaphone s-flow and its superb compared (comparison made between acceleration and top end powah) to the previous oval remus straight flow muffler. no doubt dat a straight flow muffler gives better top end, but my current s-flow seems to give better torque down under and revving red isnt a drama.

oh, back to our issue comparing pressure.. sorry guys, iam just happy wit dis kinda discussion.

 

[lozo]

1 bar td04 and 1 bar td05 is the same with relation to the atmospheric pressure. only that td05 has a bigger volume.

my thermo rusting already

 

[bongweeyap]

but why every one say that bigger tubine must hev thicker gasket???
since pressure is the same???

 

[lozo]

bigger turbine = more air volume

thicker gasket will increase the clearance volume of the cylinder, thus reduce the compression ratio of the engine, making the usage for bigger turbine possible. changing to thicker gasket is one of the way of lowering the compression ratio.

 

[HanJackaL]

Air volume that can be contained in a cylinder is fixed.Its impossible for a 2 liter cylinder to suddenly combust 2.2 liters of air,unless its been rebored and stroke has been increased.What changes is only 2 things :

1)How fast the air enters the cylinder (bigger turbos,port and polish,high lift cams..etc) help with that.

2)How much the air is compressed. With higher boost,air molecules is compressed so that more air molecules can be fit into the cylinder. More air molecules = more power.Thats why bigger intercoolers help because colder air= denser = less expanding = more air molecules = more power

3)To my understanding,a bigger turbo will lag more but once it starts giving boost,it will be stronger than a small turbo for a longer time.For example,a TD04 might run out of steam at 5000 RPM where else a TD05 might run out of steam only at 6500-7000 RPM.And the torque increases because the bigger compressor is sucking in air faster than the smaller turbo.

4)If you change a bigger turbo,replacing head gasket to a thicker one is needed because you get more air molecules inside the combustion chamber.More air molecules = more oxigen = easier to combust = more chances of "knock"

Correct me if i am wrong.

I am just very confused on whether bigger turbos actually increases power if everything is at the optimum level.For example,if you get good reponse and the power curve does not drop on high end using TD04,will it actually help if you use TD05?Since even though you get more torque(faster air flow),you get boost later so its sort of a trade off.

 

[Mat_Isam]

wah, so many info....but whatever it is i love GSR
with td04.....no need to drop gear when 'potong' even in low speed....
damn fast compared to evo (lag lorr)
but when full boosting evo come and say good bye ....
hahaha...........

 

[jinkl]

HanJackaL : bigger turbine doesnt mean confirm lag , there are alwiz ways to overcome that , u can compare evo 9 turbine with evo8
evo 9 is MUCH bigger in size and CFM compared to evo8 , both has same displacements.
here is the pic
http://img204.imageshack.us/img204/326/e9vse8turbocomparo0hq.jpg

there are also better ways to make a big turbine spool up

twinscroll : twin scroll designs meaning that the engines exhaust is divided into two channels . As the engine exhausts in pulses.. its supposed to result in quicker spooling.

ballbearing : very fast spooling compare to journal turbos :P

standalone : tuning up , playing with ingition , timing and a/f.

believe or not , t04r turbines capable of 500+hp on 2.0 car spools up as soon as the stock turbo ? :)


and here are the cfm rate that i have , all same PSI levels but then diffrence CFM . u can also go to forced induction section and see my sticky topic to read more about turbos.

Flow Rates @ 15psi:
TDO4-9B-6CM2 265 CFM
TDO5-12A-8CM2 320 CFM
TDO4-13G-5CM2 360 CFM
TEO4-13C-6CM2 360 CFM
TDO4L-13G-6CM2 360 CFM
TDO4L-15C-8.5CM2 390 CFM
TDO5H-14B-6CM2 405 CFM
TDO5H-14G-8CM2 465 CFM
TDO5H-16G-7CM2 505 CFM
TDO5H-16G-10CM2 505 CFM
TDO6-17C-8CM2 550 CFM
TDO6H-20G-14CM2 650 CFM
TDO7S-25G-17CM2 850 CFM
TFO8L-30V-18CM2 1200 CFM

 

[xtremeleo]

a good article hanjackal, lagg in a TD05H can be reduced wit a couple of mods. but, iam not gonna discuss dat since we r comparing std turbines here.

 

[xtremeleo]

u posted very useful informations jinkl, now if i may ask for d readings for a CT9A.. pretty please..

 

[lilvee]

lilvee : dat was a good post

but as i mention, keeping a common factor(s) is important in comparing things such as flow rate, performance, of any items. iam sumone dat had been through several exhaust pipe an muffler selections (just to compare between pipe sizes, muffler types, etc), so i know the importance of back pressure, at least for my engine. iam now wit an apexi supermegaphone s-flow and its superb compared (comparison made between acceleration and top end powah) to the previous oval remus straight flow muffler. no doubt dat a straight flow muffler gives better top end, but my current s-flow seems to give better torque down under and revving red isnt a drama.

oh, back to our issue comparing pressure.. sorry guys, iam just happy wit dis kinda discussion.

Before that, let me phrase it again, the back pressure that i'm talking about is not after induction aka exhaust.... its pre induction between exhaust valve (inside the engine) and turbine inlet. This known as your "banana" laa. Too shot will give better response but will choke and give reverse back pressure... this will kill your power at high rev... and too long (esp top mount type) give u lag, but as mr mat_isham said, when it start spool... say bye bye

For me, the best exhaust set-up for turbo engine is always NO Exhaust aka short open down pipe... heh heh.. but u know la how loud it is and how its attract our mat bond...

Hanjackal....

Too many physic and thermo formula involve on your question... read terbo tech 101,102 and 103 from turbobygarrett site... soo u can found what are you looking for...

cheers and happy boosting everybody.... terbabowww... heh heh