OK, who can read this map???
OK, who can read this map???
I need someone expert to read this map and please try to explain to us as well. How much PSI this turbo can run and how laggy it will be on our 2.0 engine.
im no expert, but it looks like you will have to run pretty high boost with this turbo, that or running low boost will result in real slow spool up.
Looks like its most efficient in the 29-35ish psi range.
and it looks like you might have some surging when you are building boost at low engine rpm's.
Im new to reading compressor maps, so i might be totally off.
Looks like its most efficient in the 29-35ish psi range.
and it looks like you might have some surging when you are building boost at low engine rpm's.
Im new to reading compressor maps, so i might be totally off.
Originally Posted by EvilDylan
im no expert, but it looks like you will have to run pretty high boost with this turbo, that or running low boost will result in real slow spool up.
Looks like its most efficient in the 29-35ish psi range.
and it looks like you might have some surging when you are building boost at low engine rpm's.
Im new to reading compressor maps, so i might be totally off.
Looks like its most efficient in the 29-35ish psi range.
and it looks like you might have some surging when you are building boost at low engine rpm's.
Im new to reading compressor maps, so i might be totally off.
No problems. at least you are trying to help
Actually, I think the maximum efficiency range is from 17.5psi to 26.5psi (the center circle). I don't know a whole lot about compressor maps, but this all depends on the mass of air it is moving. As far as lag, I have no idea how to read that from a compressor map.
As far as how to read off the ideal pressure, the scale on the left is pressure ratio. The lowest level (1) is the same as 0 psi. The pressure is the same on both sides of the compressor (1:1). The center circle is where maximum efficiency is achieved, and it ranges from 2.2:1 to 2.8:1, which is about 17.5 to 26.5psi. The bottom is the mass of air flowing through the compressor. If you know the temperature of the incoming air and the volumetric flow rate, you can estimate the mass airflow.
As far as how to read off the ideal pressure, the scale on the left is pressure ratio. The lowest level (1) is the same as 0 psi. The pressure is the same on both sides of the compressor (1:1). The center circle is where maximum efficiency is achieved, and it ranges from 2.2:1 to 2.8:1, which is about 17.5 to 26.5psi. The bottom is the mass of air flowing through the compressor. If you know the temperature of the incoming air and the volumetric flow rate, you can estimate the mass airflow.
im pretty sure that the 1 is 14.7 psi
Understanding the Axis:
First we will start by looking at air flow through the turbo measured on the x-axis. Garrett uses lb/min on their maps while other companies like Mitsubishi use cubic feet per minute (cfm). Since I think it’s easier to work with cfm, we’ll convert. Every 10 lb/min is equal to 144.72 cfm, remember this.
The pressure ratio measured on the y-axis is merely the ratio of air pressure leaving to the turbo to air pressure entering the turbo. Since atmospheric pressure at sea level is 14.7 psi, if you were to run 29.4 psi of boost, the pressure ratio would be 2.
Understanding the Axis:
First we will start by looking at air flow through the turbo measured on the x-axis. Garrett uses lb/min on their maps while other companies like Mitsubishi use cubic feet per minute (cfm). Since I think it’s easier to work with cfm, we’ll convert. Every 10 lb/min is equal to 144.72 cfm, remember this.
The pressure ratio measured on the y-axis is merely the ratio of air pressure leaving to the turbo to air pressure entering the turbo. Since atmospheric pressure at sea level is 14.7 psi, if you were to run 29.4 psi of boost, the pressure ratio would be 2.
The turbo will flow up to about 500hp, you can usually take about 2.5 pr and follow the line all the way over to the last circle, look down and see how much lbs/min you flow. In this case you get about 50lbs/min or 500 crank hp.
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Originally Posted by EvilDylan
im pretty sure that the 1 is 14.7 psi
Understanding the Axis:
First we will start by looking at air flow through the turbo measured on the x-axis. Garrett uses lb/min on their maps while other companies like Mitsubishi use cubic feet per minute (cfm). Since I think it’s easier to work with cfm, we’ll convert. Every 10 lb/min is equal to 144.72 cfm, remember this.
The pressure ratio measured on the y-axis is merely the ratio of air pressure leaving to the turbo to air pressure entering the turbo. Since atmospheric pressure at sea level is 14.7 psi, if you were to run 29.4 psi of boost, the pressure ratio would be 2.
Understanding the Axis:
First we will start by looking at air flow through the turbo measured on the x-axis. Garrett uses lb/min on their maps while other companies like Mitsubishi use cubic feet per minute (cfm). Since I think it’s easier to work with cfm, we’ll convert. Every 10 lb/min is equal to 144.72 cfm, remember this.
The pressure ratio measured on the y-axis is merely the ratio of air pressure leaving to the turbo to air pressure entering the turbo. Since atmospheric pressure at sea level is 14.7 psi, if you were to run 29.4 psi of boost, the pressure ratio would be 2.
here you go doods.
http://www.geocities.com/joesaccordpage/turbosizing.zip
http://www.majesticturbo.com/images/chart4.gif
http://www.honda-tech.com/zerothread?id=142398
Its all ya need!
http://www.geocities.com/joesaccordpage/turbosizing.zip
http://www.majesticturbo.com/images/chart4.gif
http://www.honda-tech.com/zerothread?id=142398
Its all ya need!
With the EVO's 2.0L motor, it appears this turbo would be in its most efficient range when delivering up to 26psi at 5000-5500rpm, and should be able to hold onto 24psi until maybe ~8000rpm. On race fuel, it should be able to give 28psi fairly efficiently until around 6000rpm, when it would begin to taper. It looks like it would ramp up on boost quickly between ~3700-4000rpm.
It's rated ~720cfm and is good for a theoretical ~500hp.
It's rated ~720cfm and is good for a theoretical ~500hp.
Originally Posted by Ted B
With the EVO's 2.0L motor, it appears this turbo would be in its most efficient range when delivering up to 26psi at 5000-5500rpm, and should be able to hold onto 24psi until maybe ~8000rpm. On race fuel, it should be able to give 28psi fairly efficiently until around 6000rpm, when it would begin to taper. It looks like it would ramp up on boost quickly between ~3700-4000rpm.
It's rated ~720cfm and is good for a theoretical ~500hp.
It's rated ~720cfm and is good for a theoretical ~500hp.
Thank you Ted. after all this Info this map is much easier to read now.
Don't get caught up reading too much into compressor maps. It's a good starting point but there is so much more to it. When you calculate PR you have to pre turbo delta P(air filter, pipe, ect.), and delta P from your turbo to where you would be measuring intake manifold pressure. To say that the turbo is putting out X mass air flow at 20psi does could mean that you only see 16psi on your boost gauge because of pressure loss along the way.
Also just because one wheel is bigger and the chart looks like should make more power it doesn't always go that way. I've tested a bunch of turbos' and sometimes the smaller, new, more efficient wheel will make more power.
here is an article I wrote about 3 years ago on how to read compressor maps, it's basic and simple.
http://www.vfaq.com/mods/Turbo-compressor-maps.html
-Martin
Also just because one wheel is bigger and the chart looks like should make more power it doesn't always go that way. I've tested a bunch of turbos' and sometimes the smaller, new, more efficient wheel will make more power.
here is an article I wrote about 3 years ago on how to read compressor maps, it's basic and simple.
http://www.vfaq.com/mods/Turbo-compressor-maps.html
-Martin
