Updated Code: Calculator Section Idea

[GVR4592]

You lost me. Or maybe you're the one that's lost. You say a larger turbo will move the same amount of air, but will result in lower intake temperatures. So the difference in power potential between a 14b and a GT42R is intake temperature?

 

[Injected]

You lost me. Or maybe you're the one that's lost. You say a larger turbo will move the same amount of air, but will result in lower intake temperatures. So the difference in power potential between a 14b and a GT42R is intake temperature?

Dude, not cool. I'm not lost, let me explain this to you. The difference in power of a 16G at 22 psi and a GT35R at 22 psi is due to the intake difference in intake temperature since they are pressurizing the intake to the same level of boost. The cooler air from the more efficient GT34R compressor will be more dense and thus create more power. The difference in the power potential of the setups is the ability to turn a GT35R up to 30psi+ which is far outside the 16G's zone. Got it now?

 

[GVR4592]

You're just not making any sense.

The difference in power of a 16G at 22 psi and a GT35R at 22 psi is due to the intake difference in intake temperature since they are pressurizing the intake to the same level of boost. The cooler air from the more efficient GT34R compressor will be more dense and thus create more power.

So you are saying that because the air that the GT35R has pressurized is cooler than the air the 16g has pressurized, then the GT35R will make more power because of the cooler air charge. Correct?

The difference in the power potential of the setups is the ability to turn a GT35R up to 30psi+ which is far outside the 16G's zone.

So now in this statement the 16g isn't capable of producing the same power as the GT35R because of what? Intake temperature?

 

[Injected]

You're just not making any sense.



So you are saying that because the air that the GT35R has pressurized is cooler than the air the 16g has pressurized, then the GT35R will make more power because of the cooler air charge. Correct?



So now in this statement the 16g isn't capable of producing the same power as the GT35R because of what? Intake temperature?

Cooler air is more dense and contains more oxygen which means more fuel can be burned to make more power. Let's say you have a good T-25 setup making 253 hp at 6500 rpm running 14 psi. If you were to change out the turbo ONLY to an EvoIII16G turbo, at 6500 rpm running 14 psi you will see a small increase in power due to the charge being cooler. Why? Because a T-25 isn't operating within it's optimal range an is really blowing extra hot air. The 16G, however is happy to blow only 14psi all day long. The difference in the power potential of the 16G comes from its ability to support the engine at 20psi whereas a T-25 will only spike to 19 psi quickly and settle around 14 psi. Follow?

 

[GVR4592]

Ok how do I calculate the power of a 4g63 with a Evo 3 16g at 22 psi, and then calculate the power of a 4g63 with a GT35R at 22 psi?

 

[Injected]

Ok how do I calculate the power of a 4g63 with a Evo 3 16g at 22 psi, and then calculate the power of a 4g63 with a GT35R at 22 psi?

Decrease the intake temperature. By how much will depend on what compressor you are going from, the compressor you are going to, what boost level, the intercooler efficiency and intake system pressure drop. The best way to actually know what that change in temperature is would be to measure it. Your ability to use these calculations effectively will increase with your understanding of the variables and relationship between them and the output. Those with an engineering background or at least college level physics should find these concepts simple. Some will struggle to find the correlation. That is why I have a default setting for every single variable. As a person actually modifies their car and begins to understand the variables involved, he can change them to better accommodate his particular setup. Also, a person may be able to play with the calculator and come to an understanding of the variables and how they affect the outcome. It's also a learning tool. Try the working code.

 

[GVR4592]

Yeah I know nothing of engineering or physics. That's probably why I'm having trouble with this. I'm going to pm you it will be much easier and it will keep the garbage out of your thread.

 

[Quasimondo]

You're just not making any sense.



So you are saying that because the air that the GT35R has pressurized is cooler than the air the 16g has pressurized, then the GT35R will make more power because of the cooler air charge. Correct?



So now in this statement the 16g isn't capable of producing the same power as the GT35R because of what? Intake temperature?

I've tried to explain this before. You have to keep in mind that this pressure is not static like you're blowing on the end of a tube, the turbo has to force air into the engine at the same time the engine is sucking in as much air as possible. The best way to imagine this scenario is to take a straw and an empty paper towel tube and blow through each one as hard as possible. With the straw, you can force as much air as you can and not feel winded. that's your GT35R. With the paper towel roll, it doesn't take long for you to run out of breath. That's your 16G. You can maintain intake pressure with both, but obviously with the 16G, it'll be working much harder to do so and at elevated boost levels the heat generated at the 16G will be much higer than the heat generated from a GT35R.

Good work on it so far. How did you insert the code, btw? I've been working on a few calculators myself, but I never figured how to insert the code into a UBB forum.


*Edit*
I added my calculator which shows how much airflow is needed for a specific HP target, as well as instructions for plotting that number on a compressor map. Maybe this spreadsheet will work better for others.

 

[GVR4592]

Ok I have AEM EMS so I know exactly what my intake temperature is right before the intake manifold. So I should be able to use that and figure out the difference correct?

 

[dyablo]

How in the world do you get that file to work after downloading? I tried downloading the file into word and that didnt work. Tried wordpad and still no work? What Am i doning wrong?

 

[GVR4592]

Read post #5

 

[Injected]

I've tried to explain this before. You have to keep in mind that this pressure is not static like you're blowing on the end of a tube, the turbo has to force air into the engine at the same time the engine is sucking in as much air as possible. The best way to imagine this scenario is to take a straw and an empty paper towel tube and blow through each one as hard as possible. With the straw, you can force as much air as you can and not feel winded. that's your GT35R. With the paper towel roll, it doesn't take long for you to run out of breath. That's your 16G. You can maintain intake pressure with both, but obviously with the 16G, it'll be working much harder to do so and at elevated boost levels the heat generated at the 16G will be much higer than the heat generated from a GT35R.

Good work on it so far. How did you insert the code, btw? I've been working on a few calculators myself, but I never figured how to insert the code into a UBB forum.


*Edit*
I added my calculator which shows how much airflow is needed for a specific HP target, as well as instructions for plotting that number on a compressor map. Maybe this spreadsheet will work better for others.

Cool. I'm writing the code using VBScript (I believe you used Excel to generate a spreadsheet inside of a Word document) and the HTML tags work inside the post, but the scripts aren't allowed to run. I figured that if shown enough support, it would be the easiest way to integrate into a website (copy/paste). I like the explanation on using a compressor map. Perhaps if each calculator were on a different page, a "How to use this calculator" paragraph could be useful.

 

[Injected]

Ok I have AEM EMS so I know exactly what my intake temperature is right before the intake manifold. So I should be able to use that and figure out the difference correct?

Yes. Use the temp for your first turbo for the calculation. Then, use the temp for the second turbo at the same psi and rpm. That will give you the difference in power generated by the turbos due to the compressor efficiency.

I also responded to your PM. I don't mind this conversation in the thread as it shows the validity of the theoretical calculations and may help to refine them.

 

[Injected]

How in the world do you get that file to work after downloading? I tried downloading the file into word and that didnt work. Tried wordpad and still no work? What Am i doning wrong?

Eh, I'll go through it one more time. Why not.
1. download the word document from the first page.
2. open the file and select all of the text (ctrl+A) and copy it (ctrl+c).
3. open Notepad and paste (ctrl+v) the text into Notepad.
4. Save As... whatevernameyouwant.html to wherever (such as desktop).
5. Navigate to the file and open the page.
6. If you have scripting disabled, you will need to enable it, but you will be able to see the page.

I'm loading a new script now (5:30 Houston time) to include the newest sections and error messages for empty fields or non numeric fields.

Here you go guys, and let me know if there is another section or calculator that you can think of that I can include.

(Edit: I have removed this script and a newer version can be fount later in this thread.)

 

[Jeremoose]

Amazing work Keep in mind guys that he's obviously still working bugs out I took university level phsyics and calculus and know that even if you work and re-work a problem 100 times it might still be wrong and its damn frustrating. So just keep up the good work man

 

[Injected]

Amazing work Keep in mind guys that he's obviously still working bugs out I took university level phsyics and calculus and know that even if you work and re-work a problem 100 times it might still be wrong and its damn frustrating. So just keep up the good work man

Thanks.

Has anyone tried out the latest code? I've debugged the whole thing (~ 400 lines of code) and think that the latest one is good to go.

I'm racking my brains trying to think of another calculator that I can add.

So far (those who have downloaded the scripts already know) I have it calculating:

1. HP Potential of engine/turbo combination
2. Pressure Ratio
3. CMf
4. HP estimate from 1/4 trapspeed
5. 1/4 ET and trapspeed estimate from HP
6. Tire Diameter
7. Static Mass Equivalency of Rotating Mass in all 5 gears
8. Injector size calculator in both Lb/Hr and CC/min
9. Engine Displacement
10. Convertor (cc to cu in)
11. Convertor (cu in to cc)

All are working and I would like to get some feedback from those who have downloaded the working version.

 

[dyablo]

Eh, I'll go through it one more time. Why not.
1. download the word document from the first page.
2. open the file and select all of the text (ctrl+A) and copy it (ctrl+c).
3. open Notepad and paste (ctrl+v) the text into Notepad.
4. Save As... whatevernameyouwant.html to wherever (such as desktop).
5. Navigate to the file and open the page.
6. If you have scripting disabled, you will need to enable it, but you will be able to see the page.

I'm loading a new script now (5:30 Houston time) to include the newest sections and error messages for empty fields or non numeric fields.

Here you go guys, and let me know if there is another section or calculator that you can think of that I can include.

Sorry, Im not to good with computers. I managed to do everything except for #6. How do i do that on notepad?

 

[Injected]

Sorry, Im not to good with computers. I managed to do everything except for #6. How do i do that on notepad?

You change that in the browser options. It should prompt you when you try to open the file.

 

[Quasimondo]

Cool. I'm writing the code using VBScript (I believe you used Excel to generate a spreadsheet inside of a Word document) and the HTML tags work inside the post, but the scripts aren't allowed to run. I figured that if shown enough support, it would be the easiest way to integrate into a website (copy/paste). I like the explanation on using a compressor map. Perhaps if each calculator were on a different page, a "How to use this calculator" paragraph could be useful.

I'm going to try to re-write it later tonight then. I have an HTML editor, but I'm useless when it comes to writing HTML or any other web language. I'll see if my brother has the time to make a webpage out of it (unless somebody else is willing to give it a shot) and hopefully these calculators can be added to the Tech Guide once all the kinks are worked out. It'd be a great way to figure how much horsepower Turbo X can support versus Turbo Y.

 

[Injected]

I'm going to try to re-write it later tonight then. I have an HTML editor, but I'm useless when it comes to writing HTML or any other web language. I'll see if my brother has the time to make a webpage out of it (unless somebody else is willing to give it a shot) and hopefully these calculators can be added to the Tech Guide once all the kinks are worked out. It'd be a great way to figure how much horsepower Turbo X can support versus Turbo Y.

Maybe you and I can figure out a formula to determine the turbo outlet temperature using compressor efficiency and the Ideal Gas Law (pV=nRT). That would make a great calculator. Then we could take the output and create a formula that uses intercooler efficiency and come up with a good estimate as to what the intake temperature would be with using inlet temperature and pressure as inputs, and outlet temperature and pressure as outputs . This is a daunting task seeing as the compressor maps don't give an exact number for compressor efficiency, only islands. Intercooler efficiency would probably have to be calculated as well (I can't think of any sources off the top of my head). I think we could do it.

 

[Quasimondo]

I figured that out in a roundabout way using the calculators from the stealth316 site:
http://www.stealth316.com/2-turbotemp.htm

Maybe something can be worked from there, but I don't know how they did their calculations.

 

[Injected]

Hey GVR4592,
How is the calculator working for you? Have you tried selecting 12 cylinders yet?

 

[Injected]

I figured that out in a roundabout way using the calculators from the stealth316 site:
http://www.stealth316.com/2-turbotemp.htm

Maybe something can be worked from there, but I don't know how they did their calculations.

That's perfect! I'll decode their scripts and figure out what formula they used. I bet it's based on the Ideal Gas Law. We'll see.

(Man, you responded fast!)

 

[Injected]

Okay, after staring at their code for a while, I also came to the realization that their inlet pressure in in absolute, but their outlet pressure is not. That confuses the crap out of the user since it looks like the compressor is only making 1.5 psi over atmosphere. I'll fix that in my version. Also, I don't see a point in including the Pr and Dr in my version since we are only after the intake temperature. Also, I think that I will make mine one calculator that will do all of the calculations at once and spit out a temperature and pressure.

What do you guys think?

 

[GVR4592]

Hey GVR4592,
How is the calculator working for you? Have you tried selecting 12 cylinders yet?

It does something but wether or not it's accurate I can't say. I have some old logs from when I had my 16g and my intake temps at the throttle body were 113 degrees at 24 psi. With my 60 trim the temps are 107 degrees at 24 psi. According to your calculator the power difference is minimal, but seat of the pants says other wise. I need to do some more messing around with it and see what I can come up with. It could also be my intake temp sensor is not accurate, or it doesn't respond to changes in air temperature fast enough. Or am I going about this the wrong way?

I found this post about compressor efficiency and temperature and all of that good stuff. It's way over my head but maybe it will help you out with your outlet temp calculator.

http://www.teamnabr.com/cgi-bin/index.cgi?page=archives.pl&action=view&topic=3113