English: This setup is used on petrol engines as they cannot withstand the full compound effect at high boost levels. It works the same as a standard diesel compound setup but as the total boost pressure increases, exhaust flow to the HP turbo is reduced or eliminated altogether which limits the compound boost effect. I call this semi-compounding. It spools the HP (high pressure) primary turbo quickly and is good for high boost, although max power would be limited to what the large LP (low pressure) secondary turbo can make. Also used on some small diesel setups.