Almost Always Necessary:
* Timing Chain/Gear Set: The cam's timing chain or gears (depending on the year of the engine) will likely need to be replaced, especially if the new cam has different specifications. Old chains can stretch and might not properly align with the new cam's timing. Installing a new set ensures accurate timing.
* Valve Springs: The new cam's lift and duration will affect the valve train. The old valve springs might not be strong enough to adequately control the valves at higher lift, leading to valve float or damage. New springs, appropriately matched to the camshaft, are essential.
* Pushrods: The pushrods transfer force from the rocker arms to the lifters. A cam with different lift might require pushrods of a different length for proper valve adjustment. Pushrod length needs to be precisely measured and possibly adjusted.
* Lifters: While not *always* required, it's highly recommended to install new lifters with a new camshaft. Older lifters may be worn or damaged and won't operate optimally with the new cam. The new cam might have a different lifter profile, further necessitating new lifters.
Often Necessary:
* Rocker Arms: Depending on the camshaft and the type of rocker arms (roller vs. stamped), new rocker arms might be needed. High-performance cams often benefit from roller rocker arms for better efficiency.
* Timing Cover Gasket: This gasket seals the timing chain cover and will need replacing during the camshaft installation.
Possibly Necessary:
* Valve Lash Adjustment: Even with new lifters and pushrods, the valves may need re-adjusting after the cam installation to ensure proper clearance.
* Head Gaskets (rare): Only necessary if head gaskets are damaged or if significant head work is done alongside the cam install.
Things to Consider:
* Cam Specs: The specifications of the new camshaft (lift, duration, lobe separation angle) greatly determine what other components need to be changed. A milder cam might only require a few parts, whereas a high-performance cam will require significantly more.
* Engine Build: A completely stock engine will require more changes than an already modified engine (e.g., an engine with aftermarket heads).
In short: Simply changing the camshaft without addressing these other components is risky and could lead to engine damage. It's best to consult a camshaft specification sheet and a reputable engine builder for advice on what components need to be upgraded along with your new cam. Failing to do so may result in engine damage or failure.
