With the number of Honda P28 VTEC ECU’s becoming scarce, it is now even more cost effective to convert your non-VTEC p06 ECU to VTEC. Believe it or not, it isn’t all that difficult. With the right components, any OBD1 P06, PR4, or P75 ECU can be converted to be electronically equivalent to a P28.
Please note, your non-vtec ECU will need to be first socketed and a VTEC engine ROM Chip added as the VTEC components alone will not allow the ECU to properly run a VTEC engine without the correct program.
First things first, there are three different board versions for OBD1 civic / integra ECU’s. Each board version uses unique components to control VTEC operation. The three board versions are ’11F0′, ‘1720’, and ‘1980’. Open your ECU lid and in the upper right corner of the ECU board in white writing you will see an identification code similar to something like ‘2D01980-1902’. This board is categorized as a ‘1980’ board version since that is in the middle of the code.
Once, you have identified your board version, you will need to source the correct VTEC conversion parts for your specific ECU. Be careful when buying the VTEC conversion kit as not all are equal. Be sure to select a kit that uses quality components as using sub-par components will lead to occasional check engine lights for a faulty VTEC system, or even worse could fry and damage your ECU.
If you do not have a quality solder iron and either desoldering braid, or a desolder gun, now is the time to pick them up. You do not have to purchase a thousand dollar setup either. A simple setup from Radio Shack for 20-30 dollars will do the trick. Be sure to use plenty of solder flux when desoldering as well as when soldering in the new VTEC conversion components.