tad question. how to calculate afr and or stoicihiometric

[C4V Engineering]

so how would i go about calculating AFR for a modular engine. also how would i calculating stoic. what im trying to do is put them on a monitor so i can see how my engine is run because i like things to be complicated.

thanks you

[bendigo (1983-2023) RIP]

Air/Fuel for afr. You may find a better answer on google for stoichimetric calculation, It involes moles and stuff that I have no idea how to do it. There are some ecms on the workshop that do the calculations, you may be able to look at the way they do it to make it work for you.

[C4V Engineering]

Originally posted by bendigo:

Air/Fuel for afr. You may find a better answer on google for stoichimetric calculation, It involes moles and stuff that I have no idea how to do it. There are some ecms on the workshop that do the calculations, you may be able to look at the way they do it to make it work for you.

ok. ill check and see if google has anything on stoic

[Sampak]

The way the game works, it gives you the information if you use the composite output from the engine/cylinder. Going off memory since it's been a few months, but you read the Fuel "volume" and Air "volume" to get the values and divide whatever to get your ratio. Also, the tool tips when looking a Modular engine (cylinder?) shows you the actual AFR ratio.

[C4V Engineering]

Originally posted by Sampak:

The way the game works, it gives you the information if you use the composite output from the engine/cylinder. Going off memory since it's been a few months, but you read the Fuel "volume" and Air "volume" to get the values and divide whatever to get your ratio. Also, the tool tips when looking a Modular engine (cylinder?) shows you the actual AFR ratio.

yeah i know all of that. at this point its just getting that comp and get the stoic on a dial. i know it requires the AFR and temp of the engine

[bendigo (1983-2023) RIP]

I found this post on redit, I don't know if it will help with what you need.





the engines run most efficient (most power for your fuel) at 0.2 stoichiometric.

the formula to calculate the required afr is:

((14-(y*2))*(1-x))+((15-(y*5))*x)

where y is your desired stoichiometric

x is:

clamp(x,0,100)*0.01 where x is the temperature of the engine, i splited this to keep the functions readable

if you divide the air through the fuel from the composite output of the cylinder, you get the current afr of the engine.

then you can use the method of your choise to regulate your fuel and air intake.

but even if you do everything perfect, the old engines will still do 3-4 times as much with the same fuel. so, modular engines are pretty useless right now.

[C4V Engineering]

Originally posted by bendigo:

I found this post on redit, I don't know if it will help with what you need.





the engines run most efficient (most power for your fuel) at 0.2 stoichiometric.

the formula to calculate the required afr is:

((14-(y*2))*(1-x))+((15-(y*5))*x)

where y is your desired stoichiometric

x is:

clamp(x,0,100)*0.01 where x is the temperature of the engine, i splited this to keep the functions readable

if you divide the air through the fuel from the composite output of the cylinder, you get the current afr of the engine.

then you can use the method of your choise to regulate your fuel and air intake.

but even if you do everything perfect, the old engines will still do 3-4 times as much with the same fuel. so, modular engines are pretty useless right now.

yeah that gives me the afr i need for said stoic which i found from bungslist. i just thinking how to reverse engineer that.

[bendigo (1983-2023) RIP]

I am really not a maths guy. It sucks because the game uses a lot of it. There are a lot of things about it on google buy you need to know the math and atomic weights of the fuel and air and it looks like greek to me. If you google it there are a few ways you can calculate it. I just am not sure what the values are for the fuel. you might be able to use diesel and calculate it though.

[C4V Engineering]

Originally posted by bendigo:

I am really not a maths guy. It sucks because the game uses a lot of it. There are a lot of things about it on google buy you need to know the math and atomic weights of the fuel and air and it looks like greek to me. If you google it there are a few ways you can calculate it. I just am not sure what the values are for the fuel. you might be able to use diesel and calculate it though.

im very bad at math as well. i dont blame you

[Il_simo]

Originally posted by C4V Engineering:

Originally posted by bendigo:

I found this post on redit, I don't know if it will help with what you need.





the engines run most efficient (most power for your fuel) at 0.2 stoichiometric.

the formula to calculate the required afr is:

((14-(y*2))*(1-x))+((15-(y*5))*x)

where y is your desired stoichiometric

x is:

clamp(x,0,100)*0.01 where x is the temperature of the engine, i splited this to keep the functions readable

if you divide the air through the fuel from the composite output of the cylinder, you get the current afr of the engine.

then you can use the method of your choise to regulate your fuel and air intake.

but even if you do everything perfect, the old engines will still do 3-4 times as much with the same fuel. so, modular engines are pretty useless right now.

yeah that gives me the afr i need for said stoic which i found from bungslist. i just thinking how to reverse engineer that.

Thank you for posting this formula: I have made a guide with my findings about stoichiometry of modular engines and your discussion was very useful!!!

I think I discovered something useful for you, if you want you can take a look to my guide:
https://steamcommunity.com/sharedfiles/filedetails/?id=2786538124

[GrumpyOldMan]

Originally posted by bendigo:

but even if you do everything perfect, the old engines will still do 3-4 times as much with the same fuel. so, modular engines are pretty useless right now.

I'm getting ~300kts with a 4cyl 3x3 on a 10m boat. Prefab engines won't even get close to that.

[C4V Engineering]

Originally posted by GrumpyOldMan:

Originally posted by bendigo:

but even if you do everything perfect, the old engines will still do 3-4 times as much with the same fuel. so, modular engines are pretty useless right now.

I'm getting ~300kts with a 4cyl 3x3 on a 10m boat. Prefab engines won't even get close to that.

i once did 400 kts on a 20m boat on 3 rps

[Lawh]

One thing to note is that the engine doesn't seem to start if the afr is less than 2:1. Not sure if you can lower it later, but at least at 0.4 fuel it will not start my engine.