Chevy BBC 454 Oval Port LowRise Aluminum Intake Manifold [Black] They are five times stronger

They are five times stronger and more ridged than stock because they are made from aircraft grade aluminum alloy

Speedmaster CNC ported cylinder heads are machined on dedicated 5-axis CNC machines to ensure accuracy and better flow

Aluminum Roller Rocker Arms 1

This feature is sometimes called an air gap design

One very small

Chevy BBC 454 Oval Port LowRise Aluminum Intake Manifold [Black] They are five times strongerThe Speedmaster LowRise Manifolds are our lowest profile manifold and is also the only one that is street legal on pollution controlled vehicles. It is set up to accept a spread bore carb but comes with an adapter plate that permits the use of square bore carbs. To remain street legal with a square bore carb, you must use one that is also approved as street legal for your application.