MMMM no bodies mentioned the brake pipes!
Current toy is mx5 sport it has "big brakes" as standard they seem good
last toy FTO GPX standard are big enough but solid slightly smaller at rear but the brake bias was from memory 65% front 35% rear, woefully inadequate! So I upgraded to slotted and drilled upfront, improved somewhat, I then replaced the brake hoses all around with Goodrich ones, vast improvement.
Having also owned a Harley and even non bikers know about there lack of stopping power, easiest improvement in the world goodrich hoses! Standard hoses can and do stretch under pressure so a metal encased hose = no stretch = better braking IMO of course! with the new hoses on my bike I had on a few occasions needed to stop quickly, and on two occasions ending up with the back wheel locked (fear mainly on my part) and ending up sideways on to the car that the driver didn't see me! (both times doing 30 in a 30 just got pulled out in front of), and how anyone can not hear open pipes, and see and notice my handsome mug smiling at them!
Most cars have a brake bias to the front for obvious reasons unless your tracking the car the best option would be to upgrade the front first and try that before doing the back.
Course in an ideal world none of us would have to have ABS for emergency stops lol
well thats MHO so pull me to pieces lol