So I just installed my GM BCS. I'm NOT using the JDM map sensor, just load to control boost. When I NLTS, as soon as I grab 4th gear from 3rd I get a nice boost spike, sometimes as high as 29psi! I'm running an SMC alky kit, so i *generally* do not see knock when this happens. Kinda cool side effect, but I see knock often enough that it is bad.

Any ideas if I'm doing something wrong, or what the issue could be? Anyone else see this happen?

Here's my BCS settings: