Unusual Boost Pattern?
 

Found something unusual when testing the boost pattern on my '93. Accelerating from below 3K in third, boost pegs the needle (hand held gauge only up to 10 psi) 'til the changeover at 4.5K. Drops to 7-8 psi then returns to 10 psi peg. The strange thing is, the EXACT same thing happens again at 6.5K. Drops to 7-8 psi, returns to 10. I think it also happens again at 7.5K, but I was more concerned about starting to shift at that point. This happened three times in a row.

I know that my turbo's are leaking oil into the compressor, this is why I was testing.

Has anyone seen this before?

P.S. Car is completely stock

No one has seen this happen?

10-8-10 sounds right at the 4.5k crossover. Above that I am not too sure, I been working on secondary turbo problems since I have had my car so I haven't seen over 5psi on the secondary. Wish I could help more then that.

Re: Unusual Boost Pattern?
 

well, does it peg at exactly 10? As in, could you just be hitting 10.5 or 11 but seeing the needle pegged?

If you're getting a drop to around 7 or 8, then it's likely that you're notting getting an incredibly huge peak... Might be good to get a better gauge and test again.