The Pro-Flo XT LS3 EFI intake manifold is engineered with a large plenum and 6.25" tapered runners to deliver maximum horsepower and a broad torque band from 1500-7000+ rpm. It features a 90mm throttle bore opening that can be ported to 105mm as needed. Machined for use with a stock LS3 style MAP sensor or Edelbrock #36019 that is mounted directly to the manifold. The Pro-Flo XT LS3 EFI accepts GM OEM 90mm or Edelbrock #3869/#38693 throttle bodies. Compatible with LS3 Fuel Rail Kit #3648 (sold separately), which features -8 AN inlet and outlet. Not intended as direct replacement for late-model vehicles due to hood and cowl clearance. In testing, the Pro-Flo XT LS3 intake manifold made 16 horsepower more, and the peak power point also increased by 500 rpm compared to a competitors plastic design. The Pro-Flo XT LS3 intake manifold is the best choice for your boosted or nitrous powered LS3 engine. Throttle Body Recommendations: Edelbrock #3869/#38693 or OEM drive-by-wire style. Installation Notes: Uses LS3/ L92/L76 style individual port o-ring seals GM PN19256623 or Edelbrock #7395. Manifold Dimensions: A-9.28", B-9.68", C-17.40", D-3.02", E-15°. Port exit dimensions: 1.23” x 2.52”.