Ever get the feeling that your engine isn't quite pulling its weight? Here are a few potential problems that could be limiting the performance of your classic car.

In addition to what is listed below, it should be noted that the altitude at which the car is operated has a decided effect on performance. A car adjusted for normal altitudes will lack performance at high altitudes, whereas a car which operated normally at high altitudes may have a lean carburetor adjustment and show signs of pre-ignition when operation at sea level.

• Ignition timing incorrect.
• Centrifugal governor advance not operating properly.
• Vacuum advance not operating properly.
• Ignition points burned, pitted, sticking or bouncing (due to weak breaker are spring).
• Faulty spark plugs.
• Faulty ignition cables.
• Faulty ignition coil.
• Faulty carburetion.
• Lack of engine compression.
• Pre-ignition.
• Inoperative manifold heater valve (stuck closed).
• Restricted carburetor inlet resulting from dirty air cleaner or choke valve not fully open.
• Carburetor throttle lever loose on shaft.
• Throttle linkage not properly adjusted.
• Carburetor throttle valve not completely open.
• Carburetor accelerating pump not functioning properly.
• Improper fuel pump operation.
• Partially restricted exhaust pipe, muffler or tail pipe.
• Clutch slippage.
• Excessive rolling resistance resulting from (a) dragging breaks; (b) tight wheel bearings; (c) misalignment of power transmitting units; (d) misalignment of rear axle; (e) under inflated tires.
• Incorrect rear axle gear ratio.
• Oversize tires.
• Incorrect valve timing.
• Inaccurate speedometer (gives the impression of lack of performance).