You already have this (We hope)

• Nistune

Very effective way to tune your Nissan. Useful for cars from stock to 500+ hp.

• Jim Wolf Technologies

Stupid simple way to handle changes to your OEM ECU. NO user adjustments. Somewhat expensive, very conservative tuning, has been used by a LOT of high horsepower Z31's.

• Pocket ROMulator

Great tool for those with a decent understanding of tuning ecu's. NOT an easy/cheap alternative to Nistune or JWT.

This will never be a complete list. These are just one's I remember seeing on cars. If you have used any of these on a Z31 please contact Steve

• Motec

• SDS

• AEM

• Microtech

• Haltech

• Megasquirt