i just got done putting on my greddy kit on my civic si, and i also have a 3" downpipe on it. was wondering if any of u guys think i should be worried about boost spiking. my setup is vafc with rc 440cc injectors, greddy type 31 cooler, greddy type s bov and of course the 18g spinner.

 

You should always be worried about boost spiking. Just keep watch on your boost gauge.

 

so how do u prevent boost spikes? cause im starting to worry about my motor

 

Keep a really good eye on the boost gauge. I had a 3 inch dp on my 18g and it did tend to spike sometimes, those internal wastegates are not the best. However, I did install a MBC on it and it seemed to help a little. It never just spiked hard, it would just slowly go above where I had it set at, more of a boost creep I guess.