I fancy a crack at some of the micro nationals and we have 4 gt14b's running at my local club in bracklesham bay.
1 still using STD tyres at the moment. Mini pins work well too. Not tried rally blocks yet.
2 I use the STD motor with a hobby wing 25a speedo. Better throttle response and we've had issues with the STD esc turning off when the car rolls. Even removing the switch didn't cure this on my one. I can also run the car outdoors on astro for 8 minutes with no issues. The STD esc would cut out on full power (16t pinion). It was only 1 lap off the top 1/10 4wd at TORCH last week
3. Rtr only
4 replace the servo with an ino labs 268. The STD servo is ok until you drive a car with one of these in.
Alloy hinge pin holders recommended. The plasic ones break easily.
Spare hinge pins a must as they are quite soft
Cvd front driveshafts
Batteries - rcmodelimports 800 mah lipo's wired in parallel to make 1600 work well.
Hard servo saver spring
Hope that helps