Just added surbo to my Wira SE 1.5 M/T today.. Can feel difference in smoother gear changes and power... :D
http://www.surbo.net/disclaimer.html
Also incompatible are nitrous systems which together with the Surbo have been known to result in ignition before the cylinders, as nitrous mixtures are very combustible.
The reasons why the Surbo may not work satisfactorily even if tightly installed in the air intake may be:
1. Engine is out of tune and does not have sufficient torque to start the Surbo cycle, eg faulty carb.
2. Wheels or tyres that together increase overall wheel size. This is one of the most common causes of failure, as the Surbo system has little tolerance for such reaction.