Do these lines come with fittings and banjo bolts?

The kit includes the feed and return lines themselves. Verify fitting sizes and banjo bolt specifications against your turbo or supercharger manifold before purchase — most setups require additional hardware matched to your specific application.

Can I use these on a naturally aspirated engine?

These are sized and configured for forced induction systems. If you're running a turbo, supercharger, or external oil cooler, they work. Standard engine bay routing may not need a 40" main line — measure your layout first.

Will stainless steel lines hold up to heat and pressure cycles?

Stainless resists corrosion and oxidation better than steel, but confirm pressure ratings against your system's PSI. Oil feed pressure on most turbocharged setups runs 10–15 PSI — these lines handle that, but don't assume without checking specs on your specific charger or cooler setup.