1. By removing exhaust restrictions YOU DO NOT LOOSE TORQUE. It simply moves the PEAK torque up the rpms. Remember BHP is a calculation of torque x rpm/5252 So even if you torque number does not increase but moves 500rpm up the rev range it will INCREASE your BHP. 2. This whole thing doesn't add up. If it's bogging in 1st then it should in 2nd. It's the same engine going thru the same rev range isn't it. In addition due to gearing you would not need as much torque in 1st as you do in 2nd becuase there is less load on the engine. The engine will be (should be!) producing EXACTLY the same HP/Torque curves in every gear. So if it has a lack of power in 1st gear only you have a different problem on your hands.