[NoDOHC]

I like standalone ECUs much better than piggyback ECUs. The piggyback ECUs still have all the limitations of the factory ECU only they give adjustability. A standalone has far fewer limitations.

A Haltech E6X is not very expensive (like $800, I think) and they are easy to install and use.

I have used megasquirt before (never on a rotary) and it works quite well also (more setup and troubleshooting, but less expense).

Basically, you are trying to avoid pre-ignition (sometimes called detonation or spark-knock). If you can keep enough fuel to cool the charge and keep from igniting the charge too early, you should be ok.

I have almost no experience with a Top-mounted intercooler. The first thing I do with a stock 13BT is take that inefficient engine-killer off and get a Front-mounted intercooler (some use a vertical-mounted near the hood latch).

If you get good cool charge air (<35C) you are Ok running 13:1 AFR at 7 psi boost with 100 octane fuel (using 8.5:1). (This should get you in the 250-300 WHp range).

You could also run 15 psi, stock intercooler and 11:1 AFR with the timing retarded 10 degrees and get about 300WHp out of the same engine, while using a lot more fuel and causing much more wear and tear.

The question is, what mods are you willing to do?

If you are going to keep the stock Intercooler, you should stick with Rotary_Inspired's advice, he probably knows more about the stock intercooler than I do.