INTAKE MANIFOLD STUD, MANIFOLD TO ENGINE, ALL IDA MANIFOLDS (30mm)
Intake Manifold Stud, Manifold to Engine. All IDA Manifolds
The Racing Beat Weber IDA manifolds have a much thicker manifold-to-engine flange than OEM manifolds. This means the two rotor housing intake studs are simply too short to get a good grip with a nut.
These longer studs solve that problem (30mm). We also prefer using studs in the side housings as it makes keeping the gasket in place and lining up everything a little easier.
So — you need two if you want to do only the rotor housings or six to do the full engine.