[lxndr]

An easy swap that anyone can do to get a little more power out of thier stock Civic/CRX SI is to replace their ECU with an '86-'87 Integra ECU. The Integra ECU will plug right in to the SI wiring without any modifications. The benefit of this swap is that the Integra ECU is programed for performance and you will eliminate the Civic rev limiter. Also, when you decide to put in a D16A1 you will already have the ECU installed (although the D16A1 will run using the stock SI ECU). Be sure to pick up an ECU designed for use with your transmission (manual or automatic).

Note:
Do NOT use an ECU from an '88-'89 Integra as this ECU is designed to be used with a VSS and is therefore not compatible with the SI. The stock SI motor will confuse the '88-'89 Integra ECU causing it to run poorly.

Edit:
THE ECU IS NOT WORTH SWAPPING WITHOUT HAVING OTHER PERFORMANCE MODIFICATIONS!!!