Master Power Turbo T70 Compressor Map

[Lextreme II]

Here is the compressor map of T70 for the new turbo brand call Master Power.

Brand new! Perfect for extremely high HP engines. 0.70 A/R compressor housing. Super 70 Trim compressor wheel (flows more than 85 lbs/min). My goal is 15 psi. The T70 is running right in the island of the compressor map above. Therefore, this turbo is great between 8-27 psi. That mean lots of room for improvement. Why did i choose this turbo? I want this to be my last turbo. All I have to do is to upgrade internal parts to run the max. I also added dots for the compressor map so u can see where the effeciency located. Once again, this turbo is best runing from 15 psi to 22 psi. However, for the 4.0 liter, 20 psi is the most effecient working condition for the turbo. At 20 psi, its in the middle of the island. The red highlight is the airflow for the 1uzfe 4.0 engine. You can trace along the red line and see the boost level and horse power produced.

Here is the formula:
1UZFE Displacement = 4.0 liters = 244.09 cubic inches

Air flow equals: Cid X RPM X 0.5 X Ev divided by 1728


For 6500 redline and Ev = 0.80:

Air flow equals: 244.09.07 X 6500 X 0.5 X 0.80 = 367.26cfm divided by 1728

1lb/min = 14.472 cfm

so 367.26cfm = 25.37 lbs/min



air flow at boost = stock air flow X pressure ratio

Pressure Ratio = (boost + 14.7) divided by 14.7


So for 15psi of Boost @ 6500rpm:

Air flow = 367.26 X (15+14.7) = 742.01cfm or 51.27lbs/min divided by 14.7


Look for those compressor map with the above value and 51.27lbs/min
With the link below, you can compare pressure level with airflow in the uzfe engines. Here is a spread sheet on boost level with different UZFE engines.


Here are other compressor map of MP turbos
Master Power 60-1/62-1 Turbos

Master Power T61/T62 Turbos

Anyone can explain if this turbo is good for the 1uzfe? The price and quality is very attractive.

 

[JBrady]

David, those maps look great. Here is an EASY rule of thumb for you... each pound of air per minute equals more or less 10 horsepower!!! This makes it simple.
30lbs flow = 300hp
85lbs flow = 850hp

As long as you keep your compressor flowing enough air at any given boost level you will stay out of surge and your golden.

That 70 looks to be awesome and in the high efficiency island from 250hp at 8psi... to 675hp at 33psi.

One thing that always seems to happen, turbos make more peak power than their maps would suggest. I always attributed this to the fact that before you make any boost... you must first overcome the engines VACUUM. Think about it, an engine is flowing X amount of air to make X amount of power, so, before you can register boost there is that much air mass flowing through the compressor. So, it is not unheard of for a turbo that looks like its max is say 850hp to actually support 1000hp.

 

[Trvln Nalzmn]

On the face of it the T70 looks too big for a street car.

The 10 lb of air per 10 horsepower is just a figure based on a lot of peoples experience. I'd say that if you get 1000hp out of a turbo that has a compressor that is rated at 85lb/min then you are probably just getting a few more RPM out of the turbo and the engine is running efficiently.

 

[Lextreme II]

John,

Does the 10x rules also engine size dependant? From the T70 map above, the best would be T67 for street application. The effeciency would be right in the center.

 

[JBrady]

On the face of it the T70 looks too big for a street car.

The 10 lb of air per 10 horsepower is just a figure based on a lot of peoples experience. I'd say that if you get 1000hp out of a turbo that has a compressor that is rated at 85lb/min then you are probably just getting a few more RPM out of the turbo and the engine is running efficiently.

I am sure you mean (as I said above) 1 pound air mass = 10hp.

Why do you suggest that the reason for more output is more turbo RPM? Look at any compressor map... as the mass air nears its limit... increasing turbo RPM has virtually no effect on mass flow. You may be arguing that the particular engine is making more efficient use of a given air mass... IE 0.85lbs = 10hp. But the phenomenon occurs on virtually any engine that can exceed a compressors flow rating. This at a point in the map that efficiencies are plummeting. That is why I proposed the above theory.

 

[JBrady]

John,

Does the 10x rules also engine size dependant? From the T70 map above, the best would be T67 for street application. The effeciency would be right in the center.

David, this rule of thumb (resonable estimate) is not engine size dependent although it is somewhat engine efficiency dependent. Power is the result of converting the available energy in the air fuel mixture. The more efficient the engine is the more energy it can convert from a given quantity. In conventional and comercially available automotive engines there may be a range of 20% (reasonable guesstimate) meaning super efficient engines may make 1hp for every .9 pound of air mass and very inefficient engines may make 10hp for every 1.1 pounds of air mass. So, the rule of thumb 1lb=10hp is good for most applications. That plus the fact that peak power is a combination of turbo flow and engine flow leaves a rule of thumb as a very good estimater.

Consider how compressors are tested and their maps created. The compressor is connected to a controllable power source (typically an electric motor)... its outlet connects to a throttle valve and the inlet connected to a mass airflow meter. By varying the compressor speed and throttle opening... various pressure vs. flow points can be graphed. Outlet temperature measurements calculate efficiency at each point.

Notice on the maps there is a surge line. That line indicates the minimum amount of mass air flow for any give amount of boost (indicated as pressure ratio). For example, on the T70 map, that compressor cannot make 15psi pressure at less than 20 pounds of air mass flow (or 8psi at 10 pounds or 25psi at 40 pounds). This is below the surge line. Surge conditions are most often seen whenever you close the engine throttle while the turbo is providing boost. This is where a compressor bypass valve (AKA anti-surge valve) comes in. It dumps the pressure and the compressor avoids surge.

At the other side of the map, you notice that there is a maximum mass flow for the compressor. Each RPM line more or less points to this max, whether it is 55,000rpm or 105,000rpm the max flow at any speed or boost level is 84 pounds on this map.

Now, with that information, look again at my theory. Installed on an engine, the throttle is in fact the engine. This engine of course makes power WITHOUT the turbo. So, if the turbo has a max flow of 84 pounds (roughly 840hp) worth of air... some argue that this is the maximum amount of power that turbo engine combination can make. But, on an engine, the flow dynamics are different than on a compressor map test stand. The engine is flowing air and is in fact like a vacuum on the compressor outlet. No boost is observed until the compressor can spins fast enough to outflow the engines vacuum (boost threshold). So, the true power potential of a given turbo on any given engine is somewhere between the turbos compressor test stand maximum flow measurement AND the combination of that same turbos test stand flow PLUS the non-turbo'd engines flow.

Example:
turbo max flow = 84 lb/min air mass
engine max flow (300hp engine) = 30 lb/min air mass
Combined power potential of above engine turbo combination... somewhere between 840hp and 1140hp. Halfway is a good rule thumb guesstimate... or 840 + 1140 / 2 = 990hp.

 

[turboandrew]

Honestly I have never heard of that type of estimation. Would you expect a turbo which flows 10 lbs/min and an engine that flows (non turbo) 30 lbs/min to make 350 HP? I would expect the turbo to choke the motor and probably make less than the 300 HP made in non-turbo trim.

Check out: http://www.moreboost.org/turbos.htm

There are some real world comparisons of what the turbo is rated for and what people have dyno'd, at least on Supras. IMO, rwhp ~= lbs/min*10

IMO, a T61 could be a great turbo for someone looking to make 600 rwhp or less.

 

[Trvln Nalzmn]

Honestly I have never heard of that type of estimation. Would you expect a turbo which flows 10 lbs/min and an engine that flows (non turbo) 30 lbs/min to make 350 HP? I would expect the turbo to choke the motor and probably make less than the 300 HP made in non-turbo trim.

Check out: http://www.moreboost.org/turbos.htm

There are some real world comparisons of what the turbo is rated for and what people have dyno'd, at least on Supras. IMO, rwhp ~= lbs/min*10

IMO, a T61 could be a great turbo for someone looking to make 600 rwhp or less.

It's quite a common estimation to make but only after matched to an engine. If you look at the T70 map it can flow 90lb/min so according to the theory it will make 900hp.....but only if you can boost the motor to 30psi+

 

[Trvln Nalzmn]

David, this rule of thumb (resonable estimate) is not engine size dependent although it is somewhat engine efficiency dependent. Power is the result of converting the available energy in the air fuel mixture. The more efficient the engine is the more energy it can convert from a given quantity. In conventional and comercially available automotive engines there may be a range of 20% (reasonable guesstimate) meaning super efficient engines may make 1hp for every .9 pound of air mass and very inefficient engines may make 10hp for every 1.1 pounds of air mass. So, the rule of thumb 1lb=10hp is g.

Thats all good but the 1lb=10hp is just a figure based on peoples experience.
The airflow INTO the compressor is still the same no matter what you connect the turbo up to. The only variation is how efficiently you can convert that airflow into power.

Perhaps the 1lb=10hp figure is not based on modern fuel injected, high power ignition etc motors. I suggest that if you are getting more power then the figure maybe more like 1lb=12hp now.

A 1uzfe will do more with 40lb/min of air than a pushrod, carb engine with points ignition.

/edit

Sorry I didn't read your first post where you said that it applies to all engines. In that case then we are probably both wrong

 

[Lextreme II]

Like i said, i chose this turbo because its potential for future upgrades.... 990 bhp is too much hp for me. But again, hp is like sex, the more you have the more you want.

 

[JBrady]

Honestly I have never heard of that type of estimation. Would you expect a turbo which flows 10 lbs/min and an engine that flows (non turbo) 30 lbs/min to make 350 HP? I would expect the turbo to choke the motor and probably make less than the 300 HP made in non-turbo trim.

Check out: http://www.moreboost.org/turbos.htm

There are some real world comparisons of what the turbo is rated for and what people have dyno'd, at least on Supras. IMO, rwhp ~= lbs/min*10

IMO, a T61 could be a great turbo for someone looking to make 600 rwhp or less.

Andrew, no where did I suggest that a turbo that flows LESS than the engine NA would apply here... In fact, I am presuming a reasonably well matched engine-compressor combination.

The point I am trying to make is that the WAY the compressor is bench tested is DIFFERENT than the dynamic condition it experiences when it is feeding an engine.

This is a condition that is not uncommonly seen on factory turbo engines when trying to get the maximum output prior to a turbo upgrade. With modern large capacity turbocharger upgrades (like this T70) it is rare that someone pushes a turbo past its capacity. Do you have any examples where a turbo is taken to its maximum mass flow? That is where this condition shows up.

Now, when sizing a turbo for a given application you will not be choosing the compressor based on maximum flow but rather on efficient flow for the power level targeted... agreed?

BTW, this is MY personal theory. One I developed as a result of multiple conversations with Corky Bell in 1990. Is it absolute? No, that is why I used terms like guesstimate. Still, the phenomenon exists so there must be an explanation. If you do not like mine... please offer another. Or are you comfortable with suggesting that the maximum possible output is determined by max lbs/min on a compressor map?

 

[JBrady]

It's quite a common estimation to make but only after matched to an engine. If you look at the T70 map it can flow 90lb/min so according to the theory it will make 900hp.....but only if you can boost the motor to 30psi+

Actually, the compressor map states 84lbs/min max flow. You could theoretically place this turbo on a 840hp engine (without boost) and make 840hp at 0 psi. In fact, if my theory has validity... more than 840hp. I understand that no one would do this but this is just an extreme example of the dynamic interaction between compressor and engine.

I agree that the 10hp/lb of mass airflow is a number that has been calculated based on engine output vs. compressor capacity. I also agree that different engines have different efficiencies and therefore the number is only a benchmark... but... a pretty good one...

 

[JBrady]

Like i said, i chose this turbo because its potential for future upgrades.... 990 bhp is too much hp for me. But again, hp is like sex, the more you have the more you want.

David, as I have said in the other responses... 990hp is a guesstimate based on the max flow of the T70 compressor with a theoretical 300hp non-turbo engine flow capacity. It is also at the very limit of flow and not in a high efficiency range... not recommended target output... just an example of the possibility of the dynamic combination.

Actually... from the map... I am not convinced it wouldn't be a very good street compressor.

 

[Lextreme II]

Its funny when people ask me when do i get full boost. The question in my mind is. What is Full Boost? Some stock cars 6 psi is full boost. Some heavily modified car 25 psi is full boost. When i told them 12 psi at 4k. They seem to be disappointed. This is what they would "You should get full boost at 4k" What the hack does it mean? Can you imagine have 25 psi at 4k? You couldnt drive this car and i am sure it will be very restritive and ineffecient. Honestly speaking from the first hand experience. This turbo is very streetable and great after 2k. At normal driving personally i dont really want the turbo to work. I only want the turbo to boost when i feel the need for it. That will save my motor in the long run.

Depending on your boost level goal. If you goal is to run 8 psi forever, then this turbo might be good for it. I would chose a smaller like T61/62. However, i have bigger dreams and would like to hit 20 to 25 psi someday with build motor and this turbo should able to support that.

Honestly speaking, if we are really looking the most effecient turbo for our beloved 4.0 liter, this turbo is slightly small. A T72 or so would be the most effecient but it might not be very street friendly.

 

[Trvln Nalzmn]

JBrady I think I was looking at what you were saying wrongly. Are you saying that in the case of the T70 that on an engine it might actually end up flowing 100lb/min INTO the compressor enven though the maximum flow is rated at 84?

I was thinking you were saying that they were making 1000hp out of 84lb/min.

 

[turboandrew]

Its funny when people ask me when do i get full boost. The question in my mind is. What is Full Boost? Some stock cars 6 psi is full boost. Some heavily modified car 25 psi is full boost. When i told them 12 psi at 4k. They seem to be disappointed.

Interesting. I could get 18 psi at 4200 on the 2JZGTE with twin HKS 2835R turbos. That's 3 liters with turbos that have (I think) as much HP capabilty as your T70 (somewhere close to 85 lbs/hr). I'm not sure where I'd get 12 psi, but 4000 rpm would not surprise me. I have to wonder if your header design has affected the turbo response. Anyway, if it's good enough for you, then that's the important thing!

 

[Lextreme II]

I have to admit, its not the best design. However, for the given condition, it seem to work ok. I wish there are more room for well design turbo, but the V8 is just too tight in everywhere. From my personal experience, a T62 would be good for low boost application, but i would like to get more than just 8-15 psi. I want to make room for the future.

Remember, the Master Power Turbo parts are interchangable with Garrett T Series. I can get a small turbine A/R for faster spooling.

 

[JBrady]

JBrady I think I was looking at what you were saying wrongly. Are you saying that in the case of the T70 that on an engine it might actually end up flowing 100lb/min INTO the compressor enven though the maximum flow is rated at 84?

I was thinking you were saying that they were making 1000hp out of 84lb/min.

Basically... yes... since the engine suction is changing the pressure ratio vs. flow dynamic.

We need to remember that ALL compressor maps are based on pressure RATIO and not boost. 2.0 pressure ratio means that the output is 2x imput pressure ABSOLUTE pressure. If the atmosphere is feeding the turbo at 14.7 psi (zero pressure on a boost gauge) then output pressure is 14.7psi gauge (or 29.4psi total pressure, boost + atmosphere).

Another situation where this applies is on staged turbos. Staging means that the outlet of one compressor feeds the imput of another. This is only normally seen on extreme boost diesels where the desired boost is higher than the compressors potential. Sometimes staging takes boost over 200psi. Obviously NOT possible judging by a compressor map alone... BUT... by altering the pressure ratio you alter the compressor dynamic.

This is what is also happening with a turbo. The engine alters the compressors dynamic compared to the test stand that the map is generated on. So, in our hypothetical above... yes... compressor rated for 840hp but when coupled with the engine... more power can be made due to an increase in total air mass than compressor alone can move.

 

[Trvln Nalzmn]

Your theory sounds good the more I think about it. Have you ever thought about asking an engineer at a turbo manufactorer?

 

[Lextreme II]

According to the T70 Compressor Map above. Anyone can give an estimation of how many RWHP would produce on the 4.0 liter 1UZFE for the following boost.

8 psi
15 psi
18 psi
20 psi
22 psi
25 psi