Pulsar brakes are serious overkill for your car.
The 1.0l may struggle just to drag them along
Lot of money and work for a potentially pointless gain :/
Your car though
The amount of braking torque on the rotating wheel is affected by Pressure x CoF x Leverage x Mass
Pressure - how hard the pads are forced against the disc. the big pulsar pistons provide more clamping force at the expense of longer pedal travel.
Coefficient of Friction - dependent on material & temperature (matching pads to application is very important). All brakes have an optimum operating temperature range for max Cof but becomes inefficient outside that range.
Leverage - larger diameter disc provides more leverage
Mass - the GTIR caliper & discs is twice as heavy as the stock brakes. more rotating inertia makes it harder to accelerate & decelerate and more unsprung weight for the suspension to handle)
basically on a small 1L used only on the street, it won't induce enough kinetic energy into the pulsar brakes to get the pads within optimum temps (unless you intentionally ride the brakes while at full power down a hill) and the extra weight will hurt acceleration and economy
frictional brakes basically convert kinetic energy into heat via those 4 factors above and getting the best out of them is all about heat management.
if the pads too cold or don't heat up fast enough for your street application, pick a softer low heat material.
if the pads get too hot and fade, either pick a harder high heat material and/or manage the heat via more surface area (vented or bigger discs) and cooling (ducts, spacious wheels)