Drivetrain DFIC numbers
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Originally Posted by Dr Obnxs
I had a wonderful salad, a pretty nice piece of salmon, and a good granita, but I gotta say (and my wife agrees) that my granita is better. But to be fair, I have to clean up the mess at home, at a restaurant, you just leave it and go! Gotta love that.
Well, here's the deal. I haven't posted any data yet because my wife has had a lot of shifts at work,, and Alison (my 21 month old) isn't into testing cars yet.... So there went a few days... Then I made some brackets for the DFIC. I have a polished one, and it likes to move in the stock boots. Just finished those today. Then I did the tests...
And the results for backpressure only:
The DFIC has more of a pressure drop than the stock unit. But when you look at the turbulator density inside the unit, it's not surprising.... I was thinking that this would have similar results to the Alta flow-through. Guess I was wrong! This is a perfect example of the effect of extruded turbulators on pressure.
Before everyone draws conclusions, please remember this is only half the story. With the thermal efficiency numbers, you can figure out the density change before and after the IC. With just this data, you don't really have anything to conclude....
Matt
Well, here's the deal. I haven't posted any data yet because my wife has had a lot of shifts at work,, and Alison (my 21 month old) isn't into testing cars yet.... So there went a few days... Then I made some brackets for the DFIC. I have a polished one, and it likes to move in the stock boots. Just finished those today. Then I did the tests...
And the results for backpressure only:
The DFIC has more of a pressure drop than the stock unit. But when you look at the turbulator density inside the unit, it's not surprising.... I was thinking that this would have similar results to the Alta flow-through. Guess I was wrong! This is a perfect example of the effect of extruded turbulators on pressure.
Before everyone draws conclusions, please remember this is only half the story. With the thermal efficiency numbers, you can figure out the density change before and after the IC. With just this data, you don't really have anything to conclude....
Matt
would you be willing to explain the significance of pressure drop and thermal efficiency...what is good and bad and why...... many do not know
That's because they didn't read issue #2 of MC Squared...
for those that wonder what all this is about, the IC is to shed the heat of compression from the SC to increase molecular density. But there's no free lunch, so as you cool the air with the IC, you loose some boost.... So why does this matter? Because you decrease molecular density with pressure drop, and increase it with temp drop. So the IC needs to increase density through temp decrease more than you decrease density from the pressure drop. IT's pretty easy, but you have to use absolute units.....
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
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Originally Posted by Dr Obnxs
for those that wonder what all this is about, the IC is to shed the heat of compression from the SC to increase molecular density. But there's no free lunch, so as you cool the air with the IC, you loose some boost.... So why does this matter? Because you decrease molecular density with pressure drop, and increase it with temp drop. So the IC needs to increase density through temp decrease more than you decrease density from the pressure drop. IT's pretty easy, but you have to use absolute units.....
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
Originally Posted by Dr Obnxs
This is a gross oversimplification, but that's the basics of it.
Matt
Matt
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From: Los Angeles
Originally Posted by Dr Obnxs
for those that wonder what all this is about, the IC is to shed the heat of compression from the SC to increase molecular density. But there's no free lunch, so as you cool the air with the IC, you loose some boost.... So why does this matter? Because you decrease molecular density with pressure drop, and increase it with temp drop. So the IC needs to increase density through temp decrease more than you decrease density from the pressure drop. IT's pretty easy, but you have to use absolute units.....
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
One sentance explanation.....
you have to cool the charge more than you loose boost by cooling it.
But really, the math that I used was just division. If that's too tough, I think you need to go back to school....
Matt
But really, the math that I used was just division. If that's too tough, I think you need to go back to school....
Matt
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From: Hampton, VA
Originally Posted by 04SDmini
Oh no..... Someone broke out the ideal gas equation.... Things could get scary from here
At least it wasn't a hamiltonian operator.....
At least it wasn't a hamiltonian operator.....
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From: Damascus, MD
the other ICs numbers
Originally Posted by Dr Obnxs
for those that wonder what all this is about, the IC is to shed the heat of compression from the SC to increase molecular density. But there's no free lunch, so as you cool the air with the IC, you loose some boost.... So why does this matter? Because you decrease molecular density with pressure drop, and increase it with temp drop. So the IC needs to increase density through temp decrease more than you decrease density from the pressure drop. IT's pretty easy, but you have to use absolute units.....
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
Example 1: No IC, MCS at redline..... Boost on my car post IC is about 15 lbs. Atmospheric pressure is about 15 PSI, so absolute pressure is about 30 PSI. BUt the temp is a screaming 110 deg C, which is about 400 K. So density is about 30 PSI/ 400 K or 0.075.....
Example 2: Stock IC MCS at redline. Post IC boost is about 14 PSI so absolute pressure is now 29 PSI. But the charge temp is now 50 C or 320 K. So the molecular density is now 29/320 or .091. This is a 20% increase in the amount of oxygen that is there to burn, and 20% more gross power that can be achieved by the motor.
So for all those that just look at boost, you are missing half the information. The first example had higher boost, but would make less power because the IATs are so high.....
This is a gross oversimplification, but that's the basics of it.
Matt
What is the "Flow Through" I didn't see a reference to that one anywhere?
Alta did a prototype flow through IC. Give them a call to ask status.
and I have data on stock, oily stock, stock with thermal coating, Alta TMIC, Alta Prototype flow through, and now getting the DFIC. The stuff on the GTT was taken by BahamaBart, but he lives a far bit away, and did it on his car.
Matt
ps, now everyone stop posting so I can go do some measurement!
Matt
ps, now everyone stop posting so I can go do some measurement!
I'd love to...
but I can't control the weather! So I try to get about the same weather and go for it. And yeah, the results change all over the place for thermal efficiency depending on the test. I go for the thermal efficiency at red-line in second gear. While it's somewhat arbitrary, it's constant accross all my testing, so it gives an OK apples to apples fit. I'm not compensating for humidity, because I don't have a meter for that.
To address heat soak, I only count runs where the IATs are less the 10 C different from when I come to a stop after a conditioning run (4 mile freeway loop, 70 MPH, cruise control in 5th gear, once again, arbitrary, but constant across tests..) if the IATs rise much more, it effects the results and I throw out the runs.....
Today (DFIC testing) is a bit warmer than the other days I ran on, but less than 10 degrees F different. Should give a good indication. But for sure, these aren't completely controlled tests. Just as close as I can get with only spending some time and gas.....
And the results I post, well, you all get what you pay for!
Matt
one thing is for sure, testing ICs is a bit of a pain. All your suggestions would get better numbers, but aren't within my reach. Any other volenteers out there?
Also, I tried looking at recovery in a couple of units. I have to figure out a better way, because at speed they all recover quick. Maybe red-line in first, drop it to 4th, and then cruise along. The cars speed would be slower, so the cooling would be slower as well, giving mmore resolution to the recovery tests, but then I can't use my freeway onramp for the testing, and I'll have to find another spot for the tests....
But were thinking along the same lines...
To address heat soak, I only count runs where the IATs are less the 10 C different from when I come to a stop after a conditioning run (4 mile freeway loop, 70 MPH, cruise control in 5th gear, once again, arbitrary, but constant across tests..) if the IATs rise much more, it effects the results and I throw out the runs.....
Today (DFIC testing) is a bit warmer than the other days I ran on, but less than 10 degrees F different. Should give a good indication. But for sure, these aren't completely controlled tests. Just as close as I can get with only spending some time and gas.....
And the results I post, well, you all get what you pay for!
Matt
one thing is for sure, testing ICs is a bit of a pain. All your suggestions would get better numbers, but aren't within my reach. Any other volenteers out there?
Also, I tried looking at recovery in a couple of units. I have to figure out a better way, because at speed they all recover quick. Maybe red-line in first, drop it to 4th, and then cruise along. The cars speed would be slower, so the cooling would be slower as well, giving mmore resolution to the recovery tests, but then I can't use my freeway onramp for the testing, and I'll have to find another spot for the tests....
But were thinking along the same lines...
Originally Posted by 002
May I suggest another way to evaluate intercoolers. Daily driving temperatures will be affected by heat sink, causing deltas between tests, cars and intercoolers to be like comparing apples to oranges. Instead pick a baseline; Ambient air temp/humidity, coolant temp and intake air temp and boost. Once that has been reached do a full throttle run to redline then maintane a set speed to record the recovery time. This will show the intercoolers heat rise and recovery characteristics, which are most important to me.
efficiency is one thing, but efficiency while accellerating is another. Besides, *they are all going to get hot at a stop light.
Suggested test plan, not exact specs.
Ambient temp 75*
Humidity 50%
Intake air temp 15* delta over ambient
Coolant temp 190* or whatever the average stock temp is. (I have m7)
Run from 2k rpm to 7k rpm in 2nd gear then cruise at 3k rpm.
Group results by similar pre intercooler and boost #'s
*smart a$$es need not argue semantics.
efficiency is one thing, but efficiency while accellerating is another. Besides, *they are all going to get hot at a stop light.
Suggested test plan, not exact specs.
Ambient temp 75*
Humidity 50%
Intake air temp 15* delta over ambient
Coolant temp 190* or whatever the average stock temp is. (I have m7)
Run from 2k rpm to 7k rpm in 2nd gear then cruise at 3k rpm.
Group results by similar pre intercooler and boost #'s
*smart a$$es need not argue semantics.
Originally Posted by Dr Obnxs
Any other volenteers out there?
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From: Hampton, VA
Originally Posted by Dr Obnxs
snip...
one thing is for sure, testing ICs is a bit of a pain. All your suggestions would get better numbers, but aren't within my reach. Any other volenteers out there?
Also, I tried looking at recovery in a couple of units. I have to figure out a better way, because at speed they all recover quick. Maybe red-line in first, drop it to 4th, and then cruise along. The cars speed would be slower, so the cooling would be slower as well, giving mmore resolution to the recovery tests, but then I can't use my freeway onramp for the testing, and I'll have to find another spot for the tests....
But were thinking along the same lines...
one thing is for sure, testing ICs is a bit of a pain. All your suggestions would get better numbers, but aren't within my reach. Any other volenteers out there?
Also, I tried looking at recovery in a couple of units. I have to figure out a better way, because at speed they all recover quick. Maybe red-line in first, drop it to 4th, and then cruise along. The cars speed would be slower, so the cooling would be slower as well, giving mmore resolution to the recovery tests, but then I can't use my freeway onramp for the testing, and I'll have to find another spot for the tests....
But were thinking along the same lines...
I don't think some realize how difficult and time consuming it is. I do and it makes me appreciate your efforts more.
The tough part of testing the recovery time is what exactly are you testing?
1. You do a hard acceleration and see 200ºF on the outlet side. Then hit a nice cruise and takes 30 seconds to return to a steady state. Sounds nice but much the the rate of decline has nothing to do with IC efficiency. Mainly you're just generating less boost and thus less heat. You'll see the temps drop quite quickly as soon as you throttle off. This isn't as suddenly effective IC.
2. Nobody, at least me, wants to hammer their car hard enough to saturate the IC at a high temp. So what I have done while driving over 1,000 miles on vacation last month is watch what happens after after a rest stop. Inlet and outlet temps pretty even at ~140-50º. Much of course depends on the length of stop but usually it was 15-20 minutes. Plenty enough for a good soak.
Under these conditions return to steady state is much longer even though peak temp may be lower than the quick acceleration...
It's all common sense really but makes difficult. Add in influences such as terrain and wind direction and variability ramps up.
In short. Matt is spending a lot of time and gas doing this for everyone. Without using a test lab you'll get what you get
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From: Northampton MA
"In short. Matt is spending a lot of time and gas doing this for everyone. Without using a test lab you'll get what you get " All you need is a wind tunnel, with a dyno in it. There's got to be lots of them around...... I heard they are free to use by the public.... anytime...
Rember the air flow thread???
" All you need is a wind tunnel, with a dyno in it. There's got to be lots of them around...... I heard they are free to use by the public.... anytime...Rember the air flow thread???
I'm right near Ames Reaserch Center....
they have a big f*cker of a wind tunnel. Maybe if I ask nicely!
Anyway, what else is there to do with my time (other than everything!)
Matt
Anyway, what else is there to do with my time (other than everything!)
Matt
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Posts: 1,710
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From: Northampton MA
Originally Posted by Dr Obnxs
they have a big f*cker of a wind tunnel. Maybe if I ask nicely!
Anyway, what else is there to do with my time (other than everything!)
Matt
Anyway, what else is there to do with my time (other than everything!)
Matt
First round of TE numbers..
Hi all, at red-line, 2nd gear, the DFIC gives a thermal efficiency of ~71%.
Stock was about 64%.
Car was the same BUT now has an AGS v3 on it. I think this raises temps a bit, as the tube is Al and right behind the radiator. Also, this is red-line in 2nd (~70mph). Faster speeds or lower revs (and hence lower boost and air temps) should give a better number.
Anyway, This is a bit anti-climatic after all the hype. I'm basically confirming what every knows. The DFIC works, but I'm not seeing any efficiencies above 100%.
Matt
ps, I've got a bunch of BiM-COM data to sift through as well. I'll let you all know what I find..... when I dig through it all.
Stock was about 64%.
Car was the same BUT now has an AGS v3 on it. I think this raises temps a bit, as the tube is Al and right behind the radiator. Also, this is red-line in 2nd (~70mph). Faster speeds or lower revs (and hence lower boost and air temps) should give a better number.
Anyway, This is a bit anti-climatic after all the hype. I'm basically confirming what every knows. The DFIC works, but I'm not seeing any efficiencies above 100%.
Matt
ps, I've got a bunch of BiM-COM data to sift through as well. I'll let you all know what I find..... when I dig through it all.
I have two other numbers...
Alta Flow through 54.5%, but it has less of a pressure drop.
Alta top mount 61% but it had more pressure drop.
Anyway, I'm just confirming what everyone else who has one already knows. This works.
FWIW, the tests today were during a hotter day. ~15 deg C hotter. This shouldn't effect the efficiency numbers too much, but I sure wish the temps were about the same.
God, can I have a moment of you time? I have a little request......
Oh, I forgot. He and I don't talk. I'm agnostic!
Matt
Alta top mount 61% but it had more pressure drop.
Anyway, I'm just confirming what everyone else who has one already knows. This works.
FWIW, the tests today were during a hotter day. ~15 deg C hotter. This shouldn't effect the efficiency numbers too much, but I sure wish the temps were about the same.
God, can I have a moment of you time? I have a little request......
Oh, I forgot. He and I don't talk. I'm agnostic!
Matt