1. 1.6 engine mo, get a 4-2-1 branded headers, you can get surplus, bakal ang headers di naman madaling masira. branded ones are definitely better than locally manufactured ones... no replacement for R&D

2. If your budget can accomodate it get KNN, yes. you can use it with a simota tube.

3. forget it!!! these gadgets don't work PERIOD!