Originally Posted by Matt L

People seem to get the idea that it doesn't matter because they or someone they know has gotten away with it in the past. I have also gotten away with mixing camshaft lobes and lifters in the past and have not lost a lobe as a result.

However, any time you mismatch the used parts, you have a chance of wiping the lope clean off the camshaft. This may happen as soon as five minutes after the engine is first started. Or, as stated above, not at all.