I have looked into one and have even ran the math. I'm am only interested in lowering EGT and not enough people have ran a bombed intercooler to get any good information. My assumption is that I might get about 50F EGT reduction. I also read that there is a significant drop in boost pressure for a given engine load, like 5-10 psi.
The biggest issue I see is that an aftermarket IC or a stock IC is really a decision over diminishing returns.
From what I can gather most people buy the aftermarket IC's because 1) the stock one strung a leak or 2) they are running much higher than stock boost pressure.
What you get with a more efficient IC is a better Density Ratio (DR). If you are not familiar with DR it is basically the pressure and temperature of the air at the compressor inlet compared to the pressure and temperature of the air at the engine inlet. As you raise the air pressure (compressor) you raise the temperature. The increased pressure raises the density but the increased temperature lowers it. So for a given pressure you have less density as you raise temperature. By cooling the air you increase the density of it while holding the pressure constant so the DR increases.
Now in plain langauge this means that for a given compressor output you get more air in the engine. This
effectively increases the size of your turbo, because it is putting more air into the engine for the same amount of energy required to do it.
The mod'ed IC's that I have looked at say they do a 25% increase. So lets say that the stock IC is 74% efficient. This means that the mod'ed IC's would have a 93% efficientcy. So now I look at the engine CFM requirements. I believe this calculation is for a Dodgezilla.
For those unfamiliar
PR = Pressure Ratio - (Essentially Boost Pressure)
IE = Intercooler Efficientcy
CE = Compressor Efficientcy - (Compressor Map)
RPM =
CFM = Cubic Feet per Minute - Air the engine is consuming
WG = Waste Gate - The pressure setting
Stock
PR = 3. 6 (WG set at 38 psi with manifold at 34 psi)
IE = 74 %
CE = 70 %
RPM = 2200
CFM = 678
Banks
PR = 3. 6 (WG set at 38 psi with manifold at 34 psi)
IE = 93 %
CE = 70 %
RPM = 2200
CFM = 756
Banks - To make things even
PR = 3. 3 (WG set at 33 psi with manifold at 29 psi)
IE = 93 %
CE = 73 %
RPM = 2200
CFM = 682
So notice the two Banks calculations compared to stock. The upper one uses the stock conditions but produces about 80 CFM more. The lower one reduces boost pressure to match the CFM to stock. Also keep in mind that these calculations do not look at the pressure drop of the IC's. The aftermarket ones will have a lower drop for a given CFM so my expectation is that you would see an even larger benefit.
If you are interested there are a few more IC's to look at. I am not sure what the Banks price is, but the
Piers and the
Cool Twist sell for around $750 I think. This puts their pricing pretty close to the water and just say no to meth systems.
Now..... Buy one and test the EGT reduction for me.
Jim
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