I was wondering what kind of readings I should be getting for vacuum on an L69? I am currently getting around 13-15. I think that is low. What should I be shooting for?

 

It should be 18-19, depending on elevation.
If the cam has been changed, then that will affect it.
15 shouldn't cause any real problems.

 

I was out messing with the engine today and have a steady 16. I am concerned that I might have a worn out cam or something of that sort. It wouldn't be the end of the world. I wish someone knew whether an L69 should be pulling 20 or above. Messing with the timing does not change the reading much. Maybe a degree.

 

I've seen a more aggressively-cammed 305 pull 16", but if you were losing a lobe or 2 your vacuum reading would fluctuate and your idle would sound wrong. Have you checked for vacuum leaks from the intake gaskets?

 

I was using a scope the other day and I had cylinders dropping out on the driver's side bank. I poured water on the intake on that side and the cylinders seemed to stop dropping out. I wasn't sure enough with the results to declare it an intake leak, but you may be right on the money. How much of a fluctuation would you see if a cam was going out? Would it be really noticeable? Like a degree or more? Or just tiny fluctuations? Thanks for your input.