First thing is this: you need to run your own local cloud before updating your Photon's system firmware to disable rate limiting – Particle's cloud implements its own rate limiting on the server side, plus it's not too nice to attempt that on the cloud anyway
Local cloud instructions can be found here:
To disable rate limiting on your local cloud, you'll need to download the firmware repository locally and modify the source code. Look at spark_protocol.cpp and comment out the rate-limiting code:
