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Many ask, why did you go with a front feed? What's the difference? While there are many claims, here's some basic info:
During the design phase, knowing the 2015 GT and GT350 hood line was much lower profile, height was a severe issue. Therefore, we could not carry over the rear feed 2.9L without changing engine mounts to lower the engine, something we didn't feel was ideal for a standard production kit.
With our tremendous success of the our innovative front feed kits on the GM applications, we immediately felt this was the best way to go. With this in mind, we were able to keep the blower height up at maximum, giving us maximum area above and below the intercooler core, greatly reducing power robbing "boost stack" (unwanted restrictions in the manifold). One key feature is the SC pulley location, its .75" below the standard rotor shaft centerline, getting it lower is key for hood clearance.
One of the other features with the extra intercooler core clearance, we had excess room to make the intercooler wider and longer, giving significantly more surface area and volume then any other PD supercharger system, an astounding 318ci of volume and a face area of 64 square inches!! Simply a massive unit.
One disadvantage twin-screw and TVS superchargers have always had is the discharge port and discharge direction. With traditional rear feed applications, the air exits at the front of the compressor in a forward direction. It takes a "deflector" to help move the air towards the top of the intercooler. If you move the compressor back to get the discharged air above the core, you run into the firewall, thus, for fitment purposes, PD kit builders had to slide the SC forward to gain firewall clearance. This created multiple issues. First, the bulk of the SC, the height and width creates a hood clearance issue. Second, the discharge is facing forward with the direction of the airflow also moving forward.
With the front feed design, the discharge is exiting the center of the core, which allows the air to go forward and backwards. With the increased plenum volume below the supercharger, you get very equal distribution above and below the IC core, getting less pressure drop, increased heat rejection and overall better airflow. From the cut-away image, you can see the massive plenuem above the core and the open area above the core. Allowing the entire core to be used.
Because we didn't have to sacrifice packaging, the actual intake manifold is significantly larger. Why? To decrease "boost stack" with much bigger runners, bigger plenum and more clearance on all sides of the intercooler core (top, bottom and sides), power robbing boost stack is a thing of the past. Some have argued about pressure drop above and below the IC core, but in our findings, this was not just due to poor intercooler packaging, but also minimal sized runners and tight clearances below and to the side of the IC core, causing increased manifold pressure that robs actual engine power.
Another unique feature most don't talk or know much about, the intercooled bypass system. A PD supercharger, during any use in which its not creating its built in pressure ratio, has a massive pressure differential. This pressure differential makes the supercharger "consume' more energy, while increasing operating temperatures. To combat this, one must use a bypass system which equalizes the pressure differential at the inlet of the supercharger to the post side of the supercharger. This frees up the supercharger and greatly reduces power consumption and temp. But, with the ever growing supercharger sizes, the pressure differential has been steadily growing while the bypass system have not, as they cannot pass enough volume to equalize the pressure differential. Therefore, we designed a 2.0" butterfly vs the standard 1.3 and 1.54". Many ask why would this matter. When your cruising down the highway, if your bypass system doesn't equalize the pressure, you will create excess heat. This puts more stress on your heat exchanger system. This also means during tip-in, many will see more burst knock because the air temp is just to high. Especially with systems that are running dual temp sensors (IAT1 vs IAT2). The Whipple system circulates cool air, below the IC core to the inlet of the SC, keeping the SC cool when normal driving, significantly lowering potential burst knock and unwanted detonation.
While the intercooler alone is worth massive power gains and previously unheard of safe production power levels, the true key to the front feed is its inlet design. While the rear feeds have worked really well in the past and certainly do well, the front feed significantly increases supercharger efficiency and airflow. As the pictures show, the airpath from the front feed is not only the shortest of the PD applications, but has the least amount of change of direction. Simple airflow principles, airflow decreases with turns, especially tight restrictive inlets. By decreasing the turns on the inlet path, the actual compressor efficiency increased. The front feed also has a very short intake path, further lowering inlet restrictions where the rear feed needs to duct from the filter, over the valve cover, around the brake booster, in front of the firewall and into the supercharger. PD superchargers are sensitive to having the proper volume of air during the inlet fill cycle, thus a small inlet on the inlet side leads to improper rotor filling, lowering overall VE. The front feed, with its short path, uses the entire intake track as its volume for the rotor filling. No pinch points, no hard turns to cause turbulence or improper airflow.
During the design and testing phase, we found that many of our mono blade throttle bodies could flow even more air in a smaller package. We came up with the unique elliptical, or better dubbed, the Roval throttle body which significantly outflows the traditional flat top and bottom rectangle shape blade/body. The elliptical allows for the high volume of the typical rectangle shape, but significantly picks up airflow volume with its constant radius shape. Allowing the 132mm throttle to outflow our twin 68, twin 71, twin 75 and our 168mm mono-blade, yet with the constant radius and smaller size, we were able to control throttle position and drive-ability like no other oversized throttle body.
Some claim the jack-shaft is power robbing. The reality, less than 2hp power consumption at 18,000rpm. Significantly lower than the gains picked up from the larger intercooler, manifold and supercharger.
During the design phase, knowing the 2015 GT and GT350 hood line was much lower profile, height was a severe issue. Therefore, we could not carry over the rear feed 2.9L without changing engine mounts to lower the engine, something we didn't feel was ideal for a standard production kit.
With our tremendous success of the our innovative front feed kits on the GM applications, we immediately felt this was the best way to go. With this in mind, we were able to keep the blower height up at maximum, giving us maximum area above and below the intercooler core, greatly reducing power robbing "boost stack" (unwanted restrictions in the manifold). One key feature is the SC pulley location, its .75" below the standard rotor shaft centerline, getting it lower is key for hood clearance.
One of the other features with the extra intercooler core clearance, we had excess room to make the intercooler wider and longer, giving significantly more surface area and volume then any other PD supercharger system, an astounding 318ci of volume and a face area of 64 square inches!! Simply a massive unit.
One disadvantage twin-screw and TVS superchargers have always had is the discharge port and discharge direction. With traditional rear feed applications, the air exits at the front of the compressor in a forward direction. It takes a "deflector" to help move the air towards the top of the intercooler. If you move the compressor back to get the discharged air above the core, you run into the firewall, thus, for fitment purposes, PD kit builders had to slide the SC forward to gain firewall clearance. This created multiple issues. First, the bulk of the SC, the height and width creates a hood clearance issue. Second, the discharge is facing forward with the direction of the airflow also moving forward.
With the front feed design, the discharge is exiting the center of the core, which allows the air to go forward and backwards. With the increased plenum volume below the supercharger, you get very equal distribution above and below the IC core, getting less pressure drop, increased heat rejection and overall better airflow. From the cut-away image, you can see the massive plenuem above the core and the open area above the core. Allowing the entire core to be used.
Because we didn't have to sacrifice packaging, the actual intake manifold is significantly larger. Why? To decrease "boost stack" with much bigger runners, bigger plenum and more clearance on all sides of the intercooler core (top, bottom and sides), power robbing boost stack is a thing of the past. Some have argued about pressure drop above and below the IC core, but in our findings, this was not just due to poor intercooler packaging, but also minimal sized runners and tight clearances below and to the side of the IC core, causing increased manifold pressure that robs actual engine power.
Another unique feature most don't talk or know much about, the intercooled bypass system. A PD supercharger, during any use in which its not creating its built in pressure ratio, has a massive pressure differential. This pressure differential makes the supercharger "consume' more energy, while increasing operating temperatures. To combat this, one must use a bypass system which equalizes the pressure differential at the inlet of the supercharger to the post side of the supercharger. This frees up the supercharger and greatly reduces power consumption and temp. But, with the ever growing supercharger sizes, the pressure differential has been steadily growing while the bypass system have not, as they cannot pass enough volume to equalize the pressure differential. Therefore, we designed a 2.0" butterfly vs the standard 1.3 and 1.54". Many ask why would this matter. When your cruising down the highway, if your bypass system doesn't equalize the pressure, you will create excess heat. This puts more stress on your heat exchanger system. This also means during tip-in, many will see more burst knock because the air temp is just to high. Especially with systems that are running dual temp sensors (IAT1 vs IAT2). The Whipple system circulates cool air, below the IC core to the inlet of the SC, keeping the SC cool when normal driving, significantly lowering potential burst knock and unwanted detonation.
While the intercooler alone is worth massive power gains and previously unheard of safe production power levels, the true key to the front feed is its inlet design. While the rear feeds have worked really well in the past and certainly do well, the front feed significantly increases supercharger efficiency and airflow. As the pictures show, the airpath from the front feed is not only the shortest of the PD applications, but has the least amount of change of direction. Simple airflow principles, airflow decreases with turns, especially tight restrictive inlets. By decreasing the turns on the inlet path, the actual compressor efficiency increased. The front feed also has a very short intake path, further lowering inlet restrictions where the rear feed needs to duct from the filter, over the valve cover, around the brake booster, in front of the firewall and into the supercharger. PD superchargers are sensitive to having the proper volume of air during the inlet fill cycle, thus a small inlet on the inlet side leads to improper rotor filling, lowering overall VE. The front feed, with its short path, uses the entire intake track as its volume for the rotor filling. No pinch points, no hard turns to cause turbulence or improper airflow.
During the design and testing phase, we found that many of our mono blade throttle bodies could flow even more air in a smaller package. We came up with the unique elliptical, or better dubbed, the Roval throttle body which significantly outflows the traditional flat top and bottom rectangle shape blade/body. The elliptical allows for the high volume of the typical rectangle shape, but significantly picks up airflow volume with its constant radius shape. Allowing the 132mm throttle to outflow our twin 68, twin 71, twin 75 and our 168mm mono-blade, yet with the constant radius and smaller size, we were able to control throttle position and drive-ability like no other oversized throttle body.
Some claim the jack-shaft is power robbing. The reality, less than 2hp power consumption at 18,000rpm. Significantly lower than the gains picked up from the larger intercooler, manifold and supercharger.
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