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If you are asking what is max boost, on each, they are around 12-15psi for stock and s1, and 17 for s2. With tweeking, you can push it further, but you risk things if you don't update/grade the fuelsystem...My s2 pushes around 17-18 in the heat with a higher spike. In winter it is between 16-17(sometimes lower) with a spike around 18.