thunderstang
Member
This is what I found on the C&L site take it for what is worth. Theres a lot more about their testing. Us poo folk can only wait.
When testing the factory intake manifold, we were quite surprised to find that it flows VERY well. The TYPICAL flow rate per runner, EVEN WITH the IMRC blades in place ranged between 250 to 263 CFM. One particular port, the front driver's side port, flowed considerably better than the others. We suppose that this is due to the fact that it is the only port which syphons airflow from directly behind the left throttle body manifold opening. Since this particular runner is shrouding airflow "directly behind" the throttle body opening, this might explain why the other (rearward) runners are flowing less. Typically, there is a 4% variation "from intake runner to intake runner" on the stock manifold with a MAXIMUM deviation of 11.8% between the "best flowing" (driver's side front runner) and the lowest flowing runners. This shows that although the original manifold flows quite well, it is not "balanced" from runner to runner........
Testing of the factory intake port on the stock 3 valve cylinder head indicates a MAXIMUM flow capacity of 236 CFM. To put this in perspective, the "original" Edelbrock Performer 5.0 cylinder head designed for the 1986-1995 Mustang applications flowed a maximum of 212 CFM with the 1.9" intake valve and 220 CFM when supplied with the optional 2.02" intake valve.....
When measuring the actual airflow capacity for our new runners, we were very pleased with the results. The driver's side port flows 327.3 CFM, and the passenger's side flows 330.2 CFM. This means that the maximum deviation between ANY of the runners is .8% or 8/10ths of one percent. Compared to the factory manifold, this indicates a flow increase of as much as 30.3%, and a port efficiency that is 96% of the maximum possible flow that the port will allow. Even when testing the runner cores mounted inside of a model that simulates our plenum configuration, flow does not go below 320 CFM. So, we were able to meet our flow requirements to support "the best" head flow capacity that is currently available. Using this intake manifold on ANY existing 3 valve cylinder head will not pose a restriction on performance.
When testing the factory intake manifold, we were quite surprised to find that it flows VERY well. The TYPICAL flow rate per runner, EVEN WITH the IMRC blades in place ranged between 250 to 263 CFM. One particular port, the front driver's side port, flowed considerably better than the others. We suppose that this is due to the fact that it is the only port which syphons airflow from directly behind the left throttle body manifold opening. Since this particular runner is shrouding airflow "directly behind" the throttle body opening, this might explain why the other (rearward) runners are flowing less. Typically, there is a 4% variation "from intake runner to intake runner" on the stock manifold with a MAXIMUM deviation of 11.8% between the "best flowing" (driver's side front runner) and the lowest flowing runners. This shows that although the original manifold flows quite well, it is not "balanced" from runner to runner........
Testing of the factory intake port on the stock 3 valve cylinder head indicates a MAXIMUM flow capacity of 236 CFM. To put this in perspective, the "original" Edelbrock Performer 5.0 cylinder head designed for the 1986-1995 Mustang applications flowed a maximum of 212 CFM with the 1.9" intake valve and 220 CFM when supplied with the optional 2.02" intake valve.....
When measuring the actual airflow capacity for our new runners, we were very pleased with the results. The driver's side port flows 327.3 CFM, and the passenger's side flows 330.2 CFM. This means that the maximum deviation between ANY of the runners is .8% or 8/10ths of one percent. Compared to the factory manifold, this indicates a flow increase of as much as 30.3%, and a port efficiency that is 96% of the maximum possible flow that the port will allow. Even when testing the runner cores mounted inside of a model that simulates our plenum configuration, flow does not go below 320 CFM. So, we were able to meet our flow requirements to support "the best" head flow capacity that is currently available. Using this intake manifold on ANY existing 3 valve cylinder head will not pose a restriction on performance.
