ECU help

[Bubba Kush]

I have a B20Z, p72 obd2 ecu and I want to swap to a b18c head. Do I need to get a p72 obd1 ecu or can i run the obd2 version?

[ECU-MAN]

the P72 is for a 1.8l DOHC VTEC Engine so its the wrong ECU for a B20, doesnt matter if its OBDI or OBDII. In this case it doesnt matter what ECU your running as they will both be wrong.

you would want to be running the OBDI ECU with some kind of add-in like Hondata or Neptune and have the ECU mapped to suit the engine.

[Bubba Kush]

Correct me if I'm wrong but the ECU doesn't affect the operations of the block. The B20z and the B18a/b are the same with the exception of the bore size and stroke length. So why wouldn't I be able to run a p72 ECU?

[ECU-MAN]

P72 is mapped for a 1.8L engine

if you run it on a 2L engine the fuel and ignition maps will be out, thus your engine will run lean and possibly knock

lean fuel mixtured melt pistons, as does knocking

[Bubba Kush]

ok... thanks for the insight