OK...went out to run some data for my tuner, but not important. Never seen this before, but after boost peaked and began to level/taper down...I saw the boost gauge needle dropping to about 10 psi. I ran another run for fueling blocks and the needle didn't drop so I ran another run for boost data and the needle dropped again. I went to my shop and looked to see if I could spot something obvious but didn't. I sat and looked at the boost data and saw boost peaking at 22 psi, leveled to over 18 psi, but then climbed back to 22 psi just before redline.
So boost is there but sometimes the gauge reflects a dramatic drop. I am going to look for vacuum leaks in the hoses that support the NSP gauge, but wondered if any NSP, or non electric, boost gauge users have ever had one fail?
This is what I have:
