vacuum gauge

[bobbybelair]

I have a buddy who thinks my cam has at least one lobe problem. I put a vacuum gauge on and it gave a super steady reading of 20, right in the middle of the "good" range. I blipped the throttle solidly and the gauge went down to approximately 3 or so, then rose back to around 25 and settled back to 20. Engine fully warmed up. Possible to have a cam lobe issue and get these results?

[markm]

Most engines drop to zero at WOT and rise on deceleration, so your results are what I would expect for a stock v8.

[Rick_L]

With a wiped lobe, it won't idle nearly as high as 20", and the vacuum reading will be quite unsteady.

[markm]

My thoughts exactly Rick and any cam that idles at 20 inches is quite mild.

[bobbybelair]

That is what I thought. Mark, it's a stock 283 so it is mild.