Hi i have a Bora PD115 , which i have had remapped. I understand that that this engine, as do the 130 and 150 , power peaks at 4000 rpm, and torque at 1800. However mine feels like the power peaks around 3500,both before and after the remap. could a faulty /aged MAF be the problem? (car has done 85 k miles)

Would upgrading to a Pierburg MAF ,whether my MAF is faulty or not ,give a slight performance/economy benefit over a fully functioning bosch unit?