Do I need to clean the header and manifold surfaces before install?

Yes. Scrape off old gasket material and carbon buildup with a gasket scraper or wire brush. Wipe both surfaces clean with a rag to ensure a proper seal.

Will this gasket work with a stock manifold or only headers?

This gasket is designed for the header-to-manifold interface on your engine. Confirm your setup matches the factory bolt pattern before ordering.

What torque spec should I use when bolting it down?

Refer to your vehicle's service manual for the correct fastener torque sequence. Over-tightening can crush the aluminum and cause leaks; under-tightening will result in exhaust seepage.