kp

I'll keep it short and simple.

I have a 94 Civic CX, i swapped in a B20B about a month ago. It is currently running off the stock CX ECU which is I believe a P05. It seems to run fine, lots of power and pretty decent MPG as well.

My question is, will an OBD1 P75 (94/95 Teg LS) make the motor run any better/worse/more reliable?

I've searched through threads and I'm finding a lot of opinions rather than actual facts, anyone have any experience with this combination?

eghondachick93

thats the best option...i had a ek with a b20b swap and i had the p75 dyno tuned and everything. Ran amaizing and loved that car. If you dont take my word for it check other forums and sites.

kp

Well, reality is I'm cheap and tuning is not an option. My only concern is whether or not a stock P75 ECU will be any better then my current stock P05 ECU.

speedooo

You could send the ecu out to be socketed and have a B20 map thrown in there. And yes the P75 will be a MUCH better choice...the P05 will make it run lean...

If you can find a used socketed ecu you can buy from here...I've ordered several chips from xenocron
http://www.xenocron.com/stock-motor-...hip-p-323.html

eghondachick93

tuning isnt that expensive sometimes its worth it other times not so much but if your just wanting to get the ecu done and run, street tune it with your friends one day. it takes barely any time.

kp

Great, thanks for the input. Is this advice stemming from experience? I have one I can get very easily for about $75 but I just want to make sure I'm making a good choice.

EDIT: Btw, the list of available basemaps for those chips doesn't include B20.

kp

I'm confused by your reply. You can't tune an ECU unless you have two things: 1. A modified/socketed ECU, 2. A person who can tune an engine. Both of these things cost money.

eghondachick93

I was talking about tuning the car itself. I know u cant tune an ecu. Just asking if once u were done with that if u were tuning the car to make it as good as possible.

kp

How exactly does one tune a car?

speedooo

Give them a call and see what they can do.

Yes, it's from personal experience. I bought a p28 about 4years ago, had it socketed and used the same ecu on a d16y7, d16y8 and a b18a1 and just paid the $20 for a different chip every time I change motors. There are several options to change like vtec engagement, launch control and rev limiter.

grumblemarc

iTrader: (4)

Research <CROME>, Hondata and Neptune.
Tuning is beyond the cope of this topic and has it's own dedicated forum. It's as simple or as difficult as you make it.

eghondachick93

didn't know there was a forum police here. just conversing on things for cars. you can actually download crome for free on your computer and have full access to the software. its on the site itself.

0xenocron

That because there was never a stock B20 that used an OBD1 ECU we can use a "stock" file for...also then you would need a custom basemap setup.

http://www.xenocron.com/basemap-chip...tom-p-279.html

kp

I think you may have missed my very vague sarcasm. I was asking how someone would tune a "car" without having a modified ecu or any additional electronics.

kp

Very cool, maybe down the line I'll decide to do that but for now I'll grab that P75 and see what kind of results I get, hopefully noticeable.

kp

Forum police? Pretty sure he was just throwing in his two cents.

grumblemarc

iTrader: (4)

Stop spreading misinformation. You can download and play with it all you want but you cannot actually tune your ECU with CROME free by itself. You need other hardware as well.
I get it now.

kp

My thoughts exactly.

kp

I hate when threads are started but never have results posted.

I installed the P75 and initially didn't notice any difference. The car was warm already and it felt pretty much the exact same. It may have been the ol' butt dyno feeling something that wasn't there but I swear the engine seemed much smoother at very low rpms such as starting in first gear at a stop sign.

I didn't feel any difference in overall performance but there may have been slight improvements.

There was one improvement which really surprised me, the massive cold idle improvement.

With the P05 I would start my car in the morning at around freezing temps and the thing would barely idle at 1k rpm. I would sit in the car for about 3 or 4 minutes before I could safely drive away. If I tried to drive immediately after starting the engine it would bog and lurch, the rpms would rise and drop almost uncontrollably. It would smooth out after only a few minutes but still a pain in the ****.

Now with the P75 I started it this morning at 1 or 2 degrees (celsius) and it immediately idled at 1500 rpm, perfect. I figured it may just be a fluke but 100 feet down my street at the stop sign it still wanted to idle at 1500. There was no bogging or lurching. Making my way to work the rpms came down to the usual 600-700 rpm idle once it warmed up enough.

I'm doubtful that the P05 makes the B20 run "lean" as I'm pretty sure the O2 sensor takes over any kind of lean condition and simply runs the injectors longer to richen the mix. The ECU doesn't know what size an engine is, it just sees signals from the sensors and tries to make the best of it. I don't have any experience tuning, so I expect some members to chime in and correct me about this.

I do however believe that each ECU has a different "style" of running an engine. My old D15B7 was a slug of a motor, great on gas but slow as hell, it makes sense that the P05 for that engine would not work well with a B20 (but I don't know the actual reason why). Different mapping for injectors? Different ignition curves?

Overall, I'm happy with the change. I'm content with the feeling in the back of my head that the engine DOES run better (even if it doesn't) and I'm very happy with the P75 doing a good job controlling the IACV for my cold starts. I've been tracking my fuel economy with my iphone since May of 2011 so I'll continue tracking to see if the ECU has made any noticeable change.

kyden

of course it runs better, the map is way closer than one made for a 1.5L.

and the p05 does make it run lean, as WOT and cold engine conditions ignores the o2 sensor.

kp

Perfect, that's something I honestly didn't know, I was hoping someone would explain it. Thanks!