Will these pipes fit my existing intercooler and intake manifold?

The 2.50" diameter is standard for most aftermarket intercoolers and turbo manifolds. Before ordering, verify your intercooler outlet and intake manifold inlet are 2.50". If either is smaller (like 2.25") or larger (like 3"), you'll need adapters or a different kit.

Do I need to prep or paint these pipes before installation?

The aluminum sections ship bare and will oxidize over time if exposed to moisture. Paint or powder-coat them before or after install depending on your engine bay layout. The steel and silicone pieces don't require prep.

What fastens these pipes to the engine and intercooler?

The kit includes the piping and connectors only. You'll need to source clamps (T-bolt or hose clamps) to secure each joint and brackets to mount the hard pipe sections to your engine bay. Check your intercooler and manifold documentation for recommended clamp sizes.