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This IC has a long core, more on that following. The end tanks are very low loss but have the built in tight bend 90 degree exits that do create losses. But each instation dictates what can be done and what cannot. So ideal configuration sometimes are simply not possible. Putting an IC into a factory location imposes its own contraints.
In the pix, note the longer radius low loss elbows in Daveships 9-5 front mount IC (FMIC). This might be reducing core length, but is a better solution than a longer long core with tight 90 degree exits.
Also when possible, an oblong configuration with long end tanks and a short core is preferred to a short tank long core configuration. The long tank orientation will have much better flow rates or lower pressure drops. But long tank configurations make a narrow IC quite fat, and in some vehicle specific applications, that simply is not going to fit.
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vs
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Note in the above how the same core size gets fat with long end tanks. The long end tank config has more and shorter passages and lower flow velocities. It is generally accepted that most of the cooling in a properly sized core, occurs in the 1st 6" of core length. So a really long flow path core is definitely not a design objective.
Also, some cores, OEM cores that I have seen, have very tight narrow and long flow passages. These are very efficient from a heat exhange point of view, but the pressure losses are very high. These pressure losses make the turbo compressor work harder to get the air through the core, and that makes the compressor output hot, which is counter productive. Also the compressor needs more shaft HP from the turbine, so the wastegate is kept more closed to increase the pressure drop across the turbine. This raises the backpressure in the exhaust manifold and that directly translates into a loss of torque and power. A balance of things needs to be achieve to make an IC work well as part of a good system. Something that Saab does not seem to seek in production. But that can probably be said about many OEM IC designs. But one also sees ICs behind AC condensors too :(
And in general, for the same core charge air cross section, if space will allow, a bigger thinner core will work better then a thicker core with smaller cross sectional area. But for a fixed frontal area, a thicker or deaper core will be more efficient and have lower pressure drops.
I am not trying to detract from this product, but with the interest that folks are having, it is a good opportunity to discuss ICs in general.
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