p28 vs. p72

[russianswty]

Whats the differance between the two ecu's.

Are the pinouts the same?

 

[CRX-YEM]

pinouts are the same, the p28 is obd1 and the p72 obd2

ecu pinout https://hondaswap.com/reference-materials/ecu-pinouts-28667/

ecu list
https://hondaswap.com/reference-materials/honda-ecu-list-29129/

 

[russianswty]

refrase that

Ok let me refrase that, whats is the difference between the p28(obd1) and the
p72(obd1) ecu's. Besides the fact that one came from a d16z6 motor and one
came from a b18 vtec motor.

Does anybody know any hard facts?

 

[K2e2vin]

P72 is pretty much the same but has IAB and knock sensor board.

 

[russianswty]

knock sensor

To my knowledge all a knock sensor is for is that I can run 87 oct gas safely in a better engine (being the gsr).

But if im always running 92, I should be fine right?

But is there anyway to get that knock sensor to work with the p28 in my ef
with a ls/vtec?

 

[reikoshea]

you dont need the knock sensor. you can disable it in both Crome and Hondata, so if you plan on running a p28, just disable it.

 

[russianswty]

sensor

well what exactly is the knock sensor for?
and yeah I will be running hondata, just not now I want to save up and get
the s300 for a wapping $595.

 

[reikoshea]

knock sensor detects abnormal vibrations in the combustion chamber (usually caused by early combustion).

 

[K2e2vin]

knock sensor detects knock/detonation. When it does, it runs your car rich, reduces timing,... runs it in limp mode(VERY weak). As long as your car is tuned correctly, you don't need the knock sensor.

If you're going to spend that much on an ECU, might as well get Megasquirt/VEMS. Neptune is also a good option.