I have a question regaurding ecu compatibility.

I have a 90 crx hf, that I put a 90 Intega motor & computer in. For one reason or another, I'm wanting to convert to use OBD1. I know that I need to add the heated o2, and change the distirbutor & plugs as well as the computer, but I was looking to kill two birds with one stone.

Currently I just have a stock LS, and am looking to go ls/vtec later. I know that for OBD1 the P28 is a good choice to use for the ecu. My question is can I use the P28 ecu (with the appropriate program for a DOHC) with my stock LS motor. I know that the P28 is a vtec ecu and has separate fuel maps for when it is vtec. Can one use the P28 on a non-vtec motor? My understanding is that on a vtec motor, with the vtec solenoid unplugged, the ecu will not use the vtec fuel maps. Is that correct?

Thanks for the help in advance.

 

I also discovered that with obd1, I have to remove the resistor box & replace my injectors & injector plugs.

Anyone else have any input?

Please?

 

if you convert you can do it in few ways:
1) harness converter OBD0 to OBDI, OBDI dizzy replugged or harness replugged, injectors can stay if you use them with the resistor box, otherwise rewire and use OBDI injectors (without box), add the other wires required for the 02 as well (then vtec pressure, solenoid, knock (not necessary with p28))

2) is to rewire the harness to OBDI and same as above

now as far as your question:
yes you can use a vtec ECU on your non-vtec but it will not run very well, it will throw a constant CEL due to the lack of Vtec solenoid and vtec pressure switch.
there is a way to chip the ecu with a program which will have vtec higher then the rev limit therfore not setting the CEL/MIL code and running much better maps.