What did your boost gauge do when you left off the gas? Anything out of the normal as in where the needle drops to?
A lot of the time, comp surge like that is from the BOV spring being too stiff. Seeing as it's a 1G BOV, it could be just a little too stiff since it is crushed. Please, do try using an uncrushed BOV next time and see what happens. If it was a Greddy or a HKS there shouldn't be any kind of problem because the Greddy can be adjusted for spring stiffness and the HKS is a different setup.
My question: Can someone do a quick explanation on why an altitude change, as well as a idle Vac change, would effect spring stiffness. I can grasp the gist of it but not in terms that would make sense to other people
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