Do I need new bolts when I install this gasket?

Your factory header bolts will work fine. If they're corroded or stripped, replacement hardware is available separately — but the gasket itself comes solo.

Should I clean the sealing surfaces before install?

Yes. Wipe both the header flange and cylinder head port face with a clean rag to remove old gasket material and carbon. A smooth surface gets a better seal.

What if exhaust leaks persist after install?

Check that header bolts are torqued evenly in a cross pattern. Uneven pressure leaves gaps. If leaking continues, the header flange itself may be warped — test-fit a known good header to confirm.