Is the Saturn sl1 single cam engine an interference engine?

Answer 1

An engine is typically classified as an "interference engine" if the fully open valves occupy the same space that the piston occupies at the top of it's stroke. When the camshaft is in proper timing with the crankshaft, valves close before the piston can come in contact.

This is important to understand when an engine timing is performed with a timing belt. Timing belt failure is common after a specific number of miles have been traveled, and as such, it is essential that vehicles receive the scheduled maintenance, especially the replacement of timing belts when appropriate.

However, the 4 cylinder Saturn engines did not use a timing belt to synchronize the camshaft with the crankshaft, instead, Saturn engineers used a timing chain which typically lasts until the engine has worn to the point of needing significant repair.

Short answer, "yes". All Saturn 4 cylinder engines are classified as interference engines, as are most modern engines.