Understanding the Camshaft and Its Role in Engine Performance

The camshaft is a critical component in any internal combustion engine, responsible for actuating the intake and exhaust valves at precisely the right moments. It converts rotational motion from the crankshaft into linear motion that opens and closes valves, controlling the flow of air and fuel into the cylinders and the expulsion of exhaust gases. A correctly selected and installed camshaft can transform an engine’s power curve, delivering substantial gains in horsepower and torque across the RPM range. Summit Racing offers a wide selection of camshafts for various applications, from mild street builds to high-horsepower race engines. However, even the best cam can perform poorly—or cause catastrophic engine damage—if installation is rushed or done incorrectly.

This guide focuses specifically on common camshaft installation issues encountered when working with Summit Racing camshafts, providing detailed troubleshooting steps and preventive measures to ensure a successful swap. Whether you are installing a Summit Racing Pro SBC Camshaft or a custom grind for a big-block Ford, understanding these pitfalls will save time, money, and frustration.

Pre-Installation Preparation: Avoiding Problems Before They Start

Many installation issues stem from inadequate preparation. Before touching the engine, verify that all components are compatible with your specific Summit Racing camshaft. Check the cam’s duration, lift, lobe separation angle, and especially the intake centerline to ensure it matches your engine’s intended use and cylinder head flow characteristics. Use Summit’s online cam selector or call their tech line to confirm compatibility with your block, heads, pistons, and valvetrain.

Critical Compatibility Checks

  • Valve-to-Piston Clearance: Camshafts with higher lift and longer duration can cause the valves to contact the pistons. Measure clearance with clay or a dial indicator. Summit Racing cams often come with a spec sheet that includes recommended minimum clearances; aim for at least 0.080-inch intake and 0.100-inch exhaust clearance for safety.
  • Valve Spring Pressure: Aggressive cam profiles require stiffer valve springs to prevent float and manage higher lift. Verify that your existing springs can handle the new cam’s lift and duration. Summit Racing sells matched spring kits for many of their cam profiles.
  • Pushrod Length: A changed cam base circle diameter alters the rocker geometry. Measure pushrod length using an adjustable pushrod checker to achieve the correct rocker arm sweep pattern. Incorrect pushrod length can lead to premature wear and inaccurate valve timing.

Common Installation Issue #1: Improper Timing Alignment

Timing alignment errors top the list of frequent mistakes. Even a single tooth off on the timing chain or gear set can shift the camshaft’s position relative to the crankshaft, resulting in lost power, rough idle, backfiring, or severe engine damage. Summit Racing camshafts are ground with a keyway or a dowel pin that aligns with the cam gear; marks on the timing set must match the piston position.

How to Avoid Timing Misalignment

  • Set the engine to top dead center (TDC) on the compression stroke for cylinder #1. Use a piston stop tool to verify true TDC—don’t rely solely on the damper marks, as they can be inaccurate on worn engines.
  • Install the timing set with the cam gear dot aligned with the crankshaft gear dot when both are at the correct positions (usually 12 o’clock on the cam gear and 6 o’clock on the crank gear, but verify per your specific set). Summit Racing’s timing chain sets include clear instructions and often have multiple keyway positions for degreeing.
  • Degree the camshaft after installation. Use a timing wheel and dial indicator to confirm the intake centerline matches the cam card specification. Many Summit Racing cams are cut to a specific intake centerline; if the measured centerline is off, adjust using offset bushings or keyways.

For more detailed degreeing procedures, refer to this Camshaft Degreeing 101 guide from OnAllCylinders, a Summit Racing resource.

Common Installation Issue #2: Insufficient Lubrication and Camshaft Break-In Failure

Camshafts rely on a film of oil between the lobes and lifters to survive the first few minutes of operation. During initial startup, the oil pump may not immediately deliver oil to the top end. Using only engine oil or forgetting assembly lube can lead to lobe scuffing, lift spalling, or complete cam failure in under an hour. This is especially critical with flat-tappet cams, but even roller cams need proper lubrication.

Proper Lubrication Techniques

  • Apply a high-quality camshaft assembly lube (such as Summit Racing’s own cam lube) to every lobe, lifter face, distributor gear, and thrust surface. Do not use white lithium grease or standard chassis grease.
  • Prime the oil system before starting the engine. Use a priming tool and a drill to spin the oil pump until oil flows from all pushrod bores and lifter galleries. This ensures that oil circulates before the engine fires.
  • Follow the cam break-in procedure: run the engine at 2000–2500 RPM for 20 minutes, varying RPM slightly every few seconds. Do not let it idle during break-in, as low oil pressure and splash lubrication are insufficient for flat-tappet cams.

Summit Racing offers detailed break-in instructions with every cam; ignore them at your engine’s peril. A ruined camshaft from improper break-in is not warrantable, so always use the manufacturer’s recommended products and steps.

Common Installation Issue #3: Incorrect Torque Specifications and Bolt Failures

Under- or over-torquing camshaft retainer plate bolts, timing chain gear bolts, or cam sprocket bolts can result in bolt breakage, oil leaks, or the cam walking forward. Summit Racing camshaft kits include hardware with specific torque values, but many builders use generic torque values that don’t account for thread lubricants or other factors.

Torque Tips for Summit Racing Cams

  • Always refer to the engine manufacturer’s service manual for torque specs on the cam retainer plate (if applicable) and timing cover bolts. For Summit Racing aftermarket camshafts, the included instruction sheet will list torque values for the cam gear bolts.
  • Use a calibrated torque wrench. Stretch bolts (like some ARP fasteners) require a specific lubricant and torque-plus-angle method. Never guess, and never reuse old bolts unless they are specified as reusable.
  • For cam thrust plates (common in small-block Chevys), torque bolts to usually around 15–20 ft-lbs. Over-torquing can distort the plate and bind the cam. Under-torquing can allow axial movement, causing timing chain misalignment or distributor gear wear.

Common Installation Issue #4: Incompatible Parts and Mixing Manufacturers

While Summit Racing cams are designed to work with most standard valvetrain components, aftermarket cylinder heads, lifters, rocker arms, and pushrods can introduce clearance or geometry problems. A common mistake is pairing a Summit Racing cam designed for a specific intake lobe profile with lifters that have a different oil band location, leading to oil starvation at high RPM.

Ensuring Component Compatibility

  • Use the lifters recommended for your cam type: flat-tappet cams require specific flat-tappet lifters, and roller cams need roller lifters with the correct link bar style and tie-bar clearance. Summit Racing’s product descriptions specify compatible lifter types.
  • Check distributor gear compatibility. Some Summit Racing steel camshafts require a hardened distributor gear (usually brass or composite) to avoid premature wear. A standard cast-iron gear on a steel cam can fail rapidly.
  • Verify rocker arm geometry. After installing the cam and timing set, mock up one cylinder with the head, pushrod, rocker, and a checking spring. Use a marker on the valve stem and rotate the engine to see the rocker’s contact pattern. Adjust pushrod length or rocker shims as needed.

Common Installation Issue #5: Neglecting to Check Clearances – Valve, Piston, and Front Cover

Insufficient clearance between the valves and pistons, or between the timing chain and front cover, can cause immediate mechanical interference that destroys the engine. Additionally, the camshaft itself may hit the block’s cam tunnel if there is a casting defect or if the cam is an unusual size (especially some large-diameter billet cams).

Clearance Checks You Must Perform

  • Valve-to-Piston: As mentioned earlier, use a dial indicator to measure cam lift and rotate the engine through full travel with checking springs. At every 10 degrees of crank rotation, check that at least 0.080-inch clearance exists. With high-compression or nitrous builds, increase to 0.100–0.120 inch.
  • Valve-to-Valve: On engines with large valves and steep valve angles, intake and exhaust valves may touch each other if the cam’s overlap is too aggressive. Install two valves in adjacent bores, rotate the engine, and listen for contact. Use a feeler gauge if possible.
  • Timing Chain and Front Cover: After installing the timing set, rotate the engine manually to ensure the chain does not rub the inside of the timing cover. If it does, spacer washers on the crank or cam sprocket may be needed. Summit Racing offers offset keys and spacer kits.
  • Camshaft End Play: With the cam in place and the retainer plate installed (without the timing set), check the axial movement. Typical end play is 0.001–0.006 inch. Too much play allows the cam to walk, affecting timing and distributor gear engagement. Use a dial indicator to measure.

Step-by-Step Expanded Installation Guide for Summit Racing Camshafts

To consolidate all the advice above, here is a detailed installation procedure that incorporates best practices for avoiding common issues:

  1. Preparation and Disassembly – Disconnect the battery, drain coolant and oil, remove the radiator, fan, water pump, timing cover, and harmonic balancer. On many engines, the camshaft can be removed from the front without pulling the heads—but if you need to change valve springs or check clearances, removing the heads may be required. Gather all tools: torque wrench, dial indicator, timing set, assembly lube, piston stop, and degree wheel.
  2. Old Camshaft Removal – Rotate the engine to top dead center for cylinder #1. Remove the distributor, fuel pump pushrod (if applicable), and the camshaft retainer plate. With the timing set removed, slide the camshaft out carefully to avoid damaging cam bearings. Use a long magnet to extract a flat-tappet cam if needed.
  3. Cleaning and Inspection – Thoroughly clean the cam journals and bearing surfaces. Inspect the cam bearings for scoring or looseness. If the bearings are worn, replace them with Summit Racing cam bearing sets. Check the oil galleries for debris; a clogged lifter bore can starve the new cam.
  4. Install New Summit Racing Camshaft – Liberally apply Summit Racing cam lube to all cam lobes, journals, and lifter faces (if using flat tappets). Insert the cam slowly, rotating it to engage the cam bearings. Install the retainer plate with the correct torque. For roller cams, install the lifter retainer bars before the timing set.
  5. Timing Set Installation – Align the timing marks as described earlier. Install the cam sprocket bolts with thread-locker (medium strength) and torque to spec. For chains with a tensioner, adjust tension per manufacturer instructions. Summit Racing offers conventional and multi-index timing sets; using a keyway-style set simplifies degreeing.
  6. Degree the Camshaft – Mount a degree wheel on the crankshaft and a dial indicator on a lifter of cylinder #1 intake. Rotate the engine until the dial indicator shows maximum lift (or 0.050-inch lift points) and compare to the intake centerline on the cam card. If off by more than 2 degrees, use offset bushings or a multi-keyway cam sprocket to adjust.
  7. Check All Clearances – Install the cylinder heads (if removed) with head gaskets torqued to spec. Use checking springs from Summit Racing’s valve spring kit to verify valve-to-piston clearance and valve-to-valve clearance. Rotate the engine by hand through two full camshaft revolutions (four crank revolutions) while listening for binding.
  8. Final Assembly and Break-In – Install the timing cover, water pump, balancer, and all accessories. Fill the engine with break-in oil (ZDDP-rich) and prime the oil system. Start the engine and immediately bring it to 2000–2500 RPM. Monitor oil pressure and coolant temperature. Run for 20 minutes, then let it idle for a moment and shut down. Re-torque the head gaskets after a few heat cycles (if using iron heads).
  9. Post-Break-In Checks – After the engine cools, inspect the oil filter for metal debris, verify valve lash is still set correctly, and re-check distributor timing. A quick test drive or dyno session will confirm the cam’s performance.

Tools and Products to Simplify Your Installation

Summit Racing offers a comprehensive range of installation tools and companion products that help eliminate guesswork. For example, their Summit Racing Cam Degreeing Kit includes a wheel, dial indicator, and piston stop—everything needed for precise timing. Additionally, consider purchasing:

  • A cam bearing installation tool if you are replacing bearings.
  • A torque angle gauge for bolts that require torque-plus-angle tightening.
  • Summit Racing’s assembly lube and break-in oil additive (zinc/phosphorus booster) to protect flat-tappet cams.
  • A pushrod length checker to guarantee correct valvetrain geometry.

For additional guidance, read Summit Racing’s technical articles: Summit Racing Tech Articles cover everything from cam selection to installation.

Final Thoughts: Investing Time Now Saves Engines Later

Installing a Summit Racing camshaft is one of the most rewarding engine modifications. The power gains are tangible when the job is done right. But the margin for error is slim, and the consequences of skipping steps can be a ruined cam or even a destroyed engine. By understanding and avoiding the common installation issues covered here—timing misalignment, lubrication failures, torque mistakes, compatibility oversights, and clearance neglect—you set yourself up for a successful build that delivers the performance you paid for.

Always refer to the specific installation instructions provided with your Summit Racing camshaft, and don’t hesitate to contact Summit’s tech support if you have any doubts. Their representatives are knowledgeable and can answer questions about specific cam series or engine combinations. With careful preparation and meticulous execution, your Summit Racing camshaft will provide many miles or dyno passes of reliable, high-performance operation.