The Speedmaster intake is a dual plane basically copied from an LD4B on the bigger runner LD340. I ported one and it was ok but I personally would never run on except on maybe a very mild street car. I bought it during the 40% off Black Friday sale for my son in Colorado but sold it after I ported it. To many better intakes out there. If you got your heads for 800.00 you got a good deal this time of year. They are around 1190.00 off Speedmaster or summit. I paid around 733.00 a pair for complete heads during the sale.