Pressure drop across intercooler
Pressure drop across intercooler Guys did anyone measure pressure drop across IC? I've put "Ebay" 4" intercooler and get about 3-3.5psi pressure drop, at 14psi pre-IC I get about 11psi of boost after the intercooler. Seems too much for my current power level (somewhere around 500whp I guess).
Man that sucks. I haven't accurately measured it I guess, but when I was on the 7.5psi wastegate springs on mine, I measured 7psi at the intake manifold. So 0.5psi drop through the APS intercooler. I wonder why the ebay one is so bad? It actually looks fairly efficient.
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From: Norn Iron
Are you using the same type of gauge, tapped into the pipe or end tank the same way ?, and also verified both gauges are comparable to each other ?
bad6as, anymore details?
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From: Norn Iron
Elaborate on that ?
You cannot measure pressure on any fitting that is connected to a boost controller which effectively is an air leak so will show a reduced pressure.
it just doesnt make sense that given the area inside a 4" thick core for air to flow through, that it should post a huge restriction compared to say the 3" diameter pipe feeding it.
They may not cool very well, but the core tubes are generally quite open and should flow well, even if they dont cool well.
Before i upgraded my own DIY intercooler made up from two old cores, I had maybe only 1psi pressure drop across it, and it was a terrible design made from two smaller cores in series.
It did flow fine, it just didnt cool
A new much much larger dedicated single core with larger end tanks, and still pressure drop was similar, but now temperatures were almost halved.
You cannot measure pressure on any fitting that is connected to a boost controller which effectively is an air leak so will show a reduced pressure.
it just doesnt make sense that given the area inside a 4" thick core for air to flow through, that it should post a huge restriction compared to say the 3" diameter pipe feeding it.
They may not cool very well, but the core tubes are generally quite open and should flow well, even if they dont cool well.
Before i upgraded my own DIY intercooler made up from two old cores, I had maybe only 1psi pressure drop across it, and it was a terrible design made from two smaller cores in series.
It did flow fine, it just didnt cool
A new much much larger dedicated single core with larger end tanks, and still pressure drop was similar, but now temperatures were almost halved.
Elaborate on that ?
You cannot measure pressure on any fitting that is connected to a boost controller which effectively is an air leak so will show a reduced pressure.
it just doesnt make sense that given the area inside a 4" thick core for air to flow through, that it should post a huge restriction compared to say the 3" diameter pipe feeding it.
They may not cool very well, but the core tubes are generally quite open and should flow well, even if they dont cool well.
Before i upgraded my own DIY intercooler made up from two old cores, I had maybe only 1psi pressure drop across it, and it was a terrible design made from two smaller cores in series.
It did flow fine, it just didnt cool
A new much much larger dedicated single core with larger end tanks, and still pressure drop was similar, but now temperatures were almost halved.
You cannot measure pressure on any fitting that is connected to a boost controller which effectively is an air leak so will show a reduced pressure.
it just doesnt make sense that given the area inside a 4" thick core for air to flow through, that it should post a huge restriction compared to say the 3" diameter pipe feeding it.
They may not cool very well, but the core tubes are generally quite open and should flow well, even if they dont cool well.
Before i upgraded my own DIY intercooler made up from two old cores, I had maybe only 1psi pressure drop across it, and it was a terrible design made from two smaller cores in series.
It did flow fine, it just didnt cool
A new much much larger dedicated single core with larger end tanks, and still pressure drop was similar, but now temperatures were almost halved.
But it's not surprise cheap ICs restrict flow actually
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From: Norn Iron
You cannot use the same port as a pressure reference if there is an air leak on it, big or small.
it only takes a small leak on a small port to make a big difference. It's the very reason boost controllers work the way they do !
They give a false low pressure reading to the actuator.
re-do the test.
I'm not saying the ebay intercoolers are good. But there is no way they can be that bad. They simply have too much volume and airflow paths for them to offer such a huge restriction at such moderate airflow levels.
it only takes a small leak on a small port to make a big difference. It's the very reason boost controllers work the way they do !
They give a false low pressure reading to the actuator.
re-do the test.
I'm not saying the ebay intercoolers are good. But there is no way they can be that bad. They simply have too much volume and airflow paths for them to offer such a huge restriction at such moderate airflow levels.
You cannot use the same port as a pressure reference if there is an air leak on it, big or small.
it only takes a small leak on a small port to make a big difference. It's the very reason boost controllers work the way they do !
They give a false low pressure reading to the actuator.
re-do the test.
I'm not saying the ebay intercoolers are good. But there is no way they can be that bad. They simply have too much volume and airflow paths for them to offer such a huge restriction at such moderate airflow levels.
it only takes a small leak on a small port to make a big difference. It's the very reason boost controllers work the way they do !
They give a false low pressure reading to the actuator.
re-do the test.
I'm not saying the ebay intercoolers are good. But there is no way they can be that bad. They simply have too much volume and airflow paths for them to offer such a huge restriction at such moderate airflow levels.
Exactly! I could move MBC further up the pipe if someone doesn't want to accept the data I gathered, but I'm 99% positive it will not change readings. My MAP sensor and my Gtech both agree that boost is falling in top rpm range.
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From: Norn Iron
And I doubt the line to the MBC or pressure reference is a full 3" diameter from the turbo to receive the huge volume of air required to maintain pressure.