You are probably wondering why I listed all the companies above, right? Well I listed them because I bought them all and have used them all. I spent a lot of money and time in my days trying to make the car go fast. I believe that the fuel management system is the key to making a RX-7 go fast. Timing, Air and Fuel is what make Horse Power! You can add lights, body kits, and do a paint job, yet the car still will not go fast! The key to going fast reliability is in the turning of the fuel management system.
Some fuel management systems are very limited to what they can do. The HKS VPC, FCON, EFI, M2 and Apex~I's fuel management systems all will help you, but is limited in it's ability. All of these units are limited by you being able to tune certain RPM's with certain KPA's (map pressure.) The timing is also limited by certain RPM's. The HKS VPC and F-CON both offer no timing changes. The M2 unit is limited to whatever they decide to program in the unit.
Both the Electromotive Tech II and Haltech units are fully programable. Fuel to any RMP to any KPA. Timing to any RPM to any KPA also. Autronic is a new computer I am currently trying out on my new car and I will soon give you some feed back about it.

Autronic, EFI Trained. I recently had a chance to take the EFI 101 class offered by Ben Strader and it was probably one of the best EFI Class I have ever taken. This is where I learend about the Autronic.