kachimba88

hey guys! name's kim...and i have some questions which im hoping some if not all of you can answer! so i have this 95civic 4door LX that i had a b20b with LS trans swapped into it. i want to know if the engine is OBD1 or OBD2 ...only the engine though.

i've already read in the previous responses about the dizzy...so im going to confirm that way...next question....the car currently has a P28 ECU...(dont know why...hubby keeps trying to steal my projects -_-') anywhoo....i purchased a JDM P75 because i read that this was the ecu for a teggy LS...

which ECU will be better between the two...also im going to get it chipped soo.....let me know..thanks!

ISUBIEXI

Same as my wife's swap in her 99 Civic. I'm pretty sure its OBD2 engine, mine have always been OBD2. We have are running a obd1 p75 and it runs pretty good. It can be a little rough under 750rpm.. Personally I want to change over to a chipped p28 and play with the tune a bit but I would need to also install wideband and Vacuum gauge as well to be able to really do any tuning. Been running with the p75 for at least 3 years now with my wife driving the car like crazy and having almost no issues.

kachimba88

oh nice! yea the p28 i read was for the 91-95 ex/si ....and the p75 was for the teggy LS...right now im running with the p28...and it's alright...i had a 98 teggy LS with a b20 vtec swap back before i had kids, and that car was one of my favorites - until it got stolen - basically..im trying to replica my teggy..into my civic's shell...lol

is your P28 chipped? or just stock? with the b20map or? let me know, thanks!

24TEN

iTrader: (2)

Technically speaking OBD is really in reference to the components running the engine. And you can confirm a little bit better which car/OBD setup that engine came from if you provide the last digit unless it legitimately says B20B without the last digit.

FWIW B20's (minus the 88-91 Prelude) are quite literally the same thing as an LS but the pistons are bigger. You can smog/BAR them as B18's utilizing all B18 related smog components including the ECU so having an Integra ECU is probably as good as it can get without chipping/tuning. I would say though that running another ECU might have certain benefits but just the same may have it's down falls as well.

ISUBIEXI

I'm still running p75 on my wife's B20. The P75 runs the engine extremely well. I have never hooked up a wide band to the car so I couldn't tell you where the AF stands. P28 would need to be chipped, I don't think a Single Cam vtec ecu will run a B20 too well on the stock tune.
We plan to eventually put a Vtec head on the B20 and with that I would most likely go with a chipped P28, I believe you can chip a p75 as well but I don't know much about that. Im running a p28 on my H23vtec and it runs quite well.

Megalodong

I have a '95 EX with B20b low comression, LS (p75) intake, GSR 60mm throttle body, '99 CRV exhaust manifold to stock '95 EX catback exhaust, 240cc injectors, LS manual 5-speed. Had a P75 ECU until three weeks ago..swapped it out due to a low/hunting idle. Also, it (ecu) was narrowed down as the cause of a lean condition. Purchased a chipped basemap with o2 sensor delete from Phearable and it's running, idling very well. The owner (Mr.Vega) of Phearable confirmed that with my engine setup his chip-basemap is fine to run on without dyno tuning. However, he did say to get every ounce of power and gas mileage a dyno tune is recommended.

OP: You can send in the P28 to be socketed and basemap chipped (to an obd1) while you run the P75 in the meantime. Most places charge around $80 to socket, components, basemap-chip an existing ECU. Look into HA Motorsports (California), Phearable (Florida), Xenocron (New Jersey). I'm sure there's many others as well. In Cali ..you may not be able to run an o2 delete due to emission laws.

tony_2018

what car did the engine come out of or what engine came with that specific type of engnine? Was that car obd1 or obd2?

JRCivic1

OBD (On Board Diagnostic) system... version 0, 1, 2A or 2B is a designation of the ECU and it's diagnostic capabilities... and NOT the engine. Now it is true that the ECU version will require the engine to have specific sensor output, but these sensors/devices can be interchanged between different model years of the engine block family ("B" series for example). In the US, no B20B/Z came in an OBD-1 version... the earliest model year was 1997 in the CR-V and that vehicle utilized the OBD-2A diagnostic system version.

So, if you intend to run a chipped ECU (regardless of the version), they would ALL be OBD-1 diagnostic versions... so the engine would need a distributor, fuel injectors, IAT, ECT, TPS and MAP sensors that are compatible with the ECU.