Wow, I constantly got grief for asking this same type of question(s) before I was banned on the forum you are a staff member on.Hi Ken
Thanks for such a Unbiased opinion.
I don't think I have ever seen a more one-side description of the differences between extruded tube and fin verse bar and plate intercoolers.
If you really want add some credibility to your statements then you need to provide some type of testing data .
Perhaps COBB would like to respond or any other manufacturer of bar and plate intercoolers for that matter.
Here is some info:
mike mcginnis said:Tube and Fin - Pros
Generally weighs about half as much as a bar and plate core of similar dimensions
Generally less expensive
Generally less flow restriction within the core than bar and plate designs
Less flow restriction through the exterior allowing better flow to the rear of the core and to a radiator, AC condenser, tranny or oil cooler, etc. which may be behind it
Those with less flow restriction than bar and plate cores offer less heat rejection
Generally have more fins which means they're more likely to be damaged by rocks/debris which cuts down on cooling efficiency
Charge air entry extends beyond core wall making it more difficult for air to enter the core cleanly
Bar and Plate - Pros
Generally off greater heat rejection than tube and fin design
Those with turbulators offer even greater heat rejection
Offered in tons of varying shapes and sizes
Less likely to be damaged by rocks and debris
Charge air entry sits flush with core allowing for cleaner entry
Weighs about twice as much as a similarly size tube and fin core
Blocks more airflow to radiators, etc. which may be behind it
Those with turbulators have greater flow resistance to the charge air
ets said:On this page, you will learn nearly everything about intercoolers and how they function.. We will explain everything from the basic design, tube types, internal design and upsides and downsides of each. At the end we describe Extreme Turbo Systems intercooler design.
Tube Design: First we will discuss the two main types of tube design, square tube and oval tube. The square tube is used in bar & plate core, and the oval tube are used in the tube and fin and hybrid fin cores. The following two pictures show the tube design as if you were looking down the length of the core. Usually when looking at an intercooler that is installed on a vehicle, you see the front/back side of the tubes, either the flat end of the bar and plate, or the rounded nose of the tube and fin. Cores are usually rated based on height, where there is usually one tube per inch of height and rated in cfm.
Ambient Airflow: Between the two tube designs, external ambient airflow through the core is different. With the square nose design of the bar and plate, the flow of ambient air through the core is slightly worse than the tube and fin due to wind deflection off of the square face. Usually this is not an issue on core thicknesses up to 4" thick. In some cases with thicker cores, the bar and plate may cause some vehicles to run a couple degrees hotter at low speed. At higher speeds above 40 mph there is rarely an issue.
Square Tube Ambient Airflow
Oval Tube Ambient Airflow
Internal Tube Design: Next we will discuss the 3 main types of core design--bar and plate, extruded tube and fin, and hybrid fin.
Bar and Plate: The bar and plate design uses a square tube with a fine internal fin packing. This fine internal fin packing allows this type of core to be very efficient but due to the turbulence caused by the larger amount of fins, flow is slightly sacrificed. Since the square tube has a larger internal area compared to a oval tube of the same thickness this core still flows more air per tube compared to the other two designs.. The upsides of this core is the high efficiency and it is available in thicknesses from 3" to 5". The downside is that due to the square nose design, ambient airflow through the core is somewhat sacrificed.
Extruded Tube & Fin: Extruded Tube and fin design uses a oval tube with an extruded fin that is molded into the tube when it is built. The fin packing is not very dense which lowers the efficiency of the core but allows it to flow more air through each tube because there is less turbulence caused by the internal fins. A lot of the time the air charge will nto contact any of the fins as it travels through the core. There are several types of extruded tube and fin designs, but it is usually the least desirable since it has the lowest efficiency therefore the lowest temperature drop across the core. This can commonly lead to heat soak. The upside to this type of core is that due to the oval nose design it allows more ambient airflow through the core compared to the bar and plate and because the fin packing is not as dense, it flows well through the core (internally). The downside is that the core design is very inefficient.
Hybrid Fin: This design is a hybrid between the bar and plate and tube and fin. This type of tube uses the oval tube like the tube and fin and the dense internal fin packing like the bar and plate. The upside to this design is that it is nearly as efficient as the bar and plate, and allows more ambient airflow through the core (external airflow). The downside of this type of core is that the thickest core that is usually offered in this type is between 2.5" to 3" thick and becoming difficult to find. Griffin uses a hybrid fin type core, but the tubes are taller than average which flow well, but since the heat has to travel so far from the center of the fin to the tube wall it slightly lowers the efficiency but with the larger tube, improves airflow through the core.
Bar and Plate
Tube and Fin
Fin Packing: Here we talk about the fin packing, internal and external design. For the intercoolers that use a fine internal fin packing there are two configurations. There is the standard packing and there is the staggered fin packing. In the standard fin packing all of the fins are in-line. If you look down the tube of this design you will usually see light through the other end. In the staggered fin packing the fins are staggered so more of the air comes into contact with the fins. If you look down the tube in this design you will rarely see any light from the other end. This design is superior because it is more efficient from the air coming into contact with more fins, but will slightly hinder flow but not significantly unless it very densly packed. There are some companies that use a very dense fin packing which is one of the most efficient on the market, but also flows the least because of it. The same applies for the external fin packing between each tube. The external fin packing is usually heavier since they are exposed to oncoming objects such as rocks and debris found on the road.
Fin Design: Another factor that affects efficiency is the fin design. Fins are commonly just thin, flat pieces of aluminum. In some cases these fins are "louvered", similar to what a cheese grater would look like. These little louvers help catch the air and direct it through the fin and improve efficiency allowing the air to contact more of the fins surface area instead of just the leading edge of the fin.
Standard Fin Packing
Staggered Fin Packing
Core Configuration: There are two configurations for air to air intercoolers. Crossflow and Vertical Flow. In the pictures below, the tubes are shown in light gray with the fin packing between each tube. The crossflow are the better design because of the effiency of the longer core. Because of the longer core the air stays in the core longer allowing it to draw more heat out of the air charge. Since the crossflow is shorter in height (ie less amount of tubes) it does not flow as much as a Vertical flow core. The vertical flow core, since it has more tubes it flows significantly more air, but because the core is shorter in length, the air doesn't stay in the core long enough to draw a lot of heat out of the air charge. Vertical flow cores work well with very high horsepower applications and is usually recommended for supercharged applications.
Crossflow Core (7 Long Tubes)
Vertical Flow Core (19 Short Tubes)
Internal Airflow: As airflow travels through an intercooler it chooses the shortest path through the core. In the diagram below it shows a core with 7 tubes, lets say each tube flows 100cfm for a total of 700cfm. If you are only flowing 300 cfm through the core you are really only using 3 of the tubes, the ones directly between the inlet and outlet. As flow increases, it will begin using the upper tubes. This will also help when mounting the intercooler. If the bottom rows were covered by the bumper and the upper tubes were exposed you would not be receiving the maximum performance possible from the intercooler.