wide band O2 sensor

[aston]

Anyone used a wide band O2 sensor and data/logger to fine tune A/F ratio?

If so, which make/model did you use? Was it effective...etc?

[swbooking]

The Innovate LM-1 is what most people use on the RX-7s i work on. Were looking at getting either that or a techedge that will hook up with our microtech ECU to log the data.

[rick]

Did you get a standalone ECU Aston? I made a map adjuster to use with a stock ECU, but since the stroker is not finished, I haven't tried it. I thought about sticking it on Sarah's TJ to make sure it works, but then I decided hacking apart the harness that isn't already hacked up might not be a good idea.... I planned on plugging in a OBDI diagnostic unit and checking injector duty cycle before and after, but I'm not 100% sure that will work either...

[aston]

Did you get a standalone ECU Aston? I made a map adjuster to use with a stock ECU, but since the stroker is not finished, I haven't tried it. I thought about sticking it on Sarah's TJ to make sure it works, but then I decided hacking apart the harness that isn't already hacked up might not be a good idea.... I planned on plugging in a OBDI diagnostic unit and checking injector duty cycle before and after, but I'm not 100% sure that will work either...

I decided to go with an Innovate O2 thingy and the Apexi piggyback doo dah.

I figured that the stroker is a much more efficient air pump but no one told the computer. Seeing as power comes from burning fuel, if I don't add any more fuel I am not going to get any more power. In fact it may even be worse than stock. I did add bigger injectors etc...but I don't think that's enough. I'll find out soon enough.

From what I understand, the MAP adjuster only works in open loop mode. The Apexi works all the time.

[rick]

Well... let me know how it works. From what I've heard, you really just need larger injectors and the stock ECU will take care of mixing things properly. I was really just thinking of using the MAP adjuster to bump it up or down slightly. I'm going to run 29 lb/hr injectors. Is that correct, the MAP doesn't do anything in closed loop mode? I guess I didn't realize that...

What compression ratio is your engine built to? I saw you're having detonation problems, is that still the case? If so, is that with premium fuel?

[aston]

Well... let me know how it works. From what I've heard, you really just need larger injectors and the stock ECU will take care of mixing things properly. I was really just thinking of using the MAP adjuster to bump it up or down slightly. I'm going to run 29 lb/hr injectors. Is that correct, the MAP doesn't do anything in closed loop mode? I guess I didn't realize that...

What compression ratio is your engine built to? I saw you're having detonation problems, is that still the case? If so, is that with premium fuel?

Will do.

I have 26# injectors and adjustable pressure reg set to 50# and it's not enough. One option was to go to 30# but that felt like shooting in the dark some more.

I am not an expert, yet! But I believe in closed loop the OBD1 computer responds to the O2 sensor and only switches to the MAP in open mode. My plan was to hook up a temp sensor mounted to the fender well. This would force the computer into open loop (cold) mode even though it was nicely warmed up and I could see if it ran any better. Unfortuantely I have not been able to run my clever experiment 'cos the steering box crapped out.

Yeah, detonation. 91 gas, 9:1 cr and 050 quench.

[rick]

Right on, thanks. I guess I thought the detonation thing was only normally a problem when running a bit higher compression or too high a quench height, but it sounds like you need to get Golen on the horn? Hopefully the aluminum head and 10:1 CR will not result in the same...

[aston]

Right on, thanks. I guess I thought the detonation thing was only normally a problem when running a bit higher compression or too high a quench height, but it sounds like you need to get Golen on the horn? Hopefully the aluminum head and 10:1 CR will not result in the same...

Chad Golen is fresh outta' ideas. I asked him at the get go if any computer mods were needed and he said "oh no, blah, blah, blah"

So far my Golen stroker has been a PITA, I would not go down this road again.

I have spent a lot of money and it still runs like a dog.

[rick]

I don't think any computer mods normally are necessary, that's why this is so perplexing (plus, I'm not planning any computer mods!)

[aston]

report

To cut a long story short I am using an Innovate LM-1 to measure actual A/F ratios and an Apexi SAFC-II to modify fuel maps.

So here's the initial data...

Baseline data (no corrections, as is) a vast simplification of course, various AFR ratios:

< 3,000 rpm 14.5
> 3,000 rpm 12.5 - 11
< 40% throttle 14.5
> 40% throttle 13 - 11

So...low throttle, low rpm basically OK but could do with some more gas if we are interested in power rather than economy.

Medium throttle, medium rpm, getting kinda' lean, definitely need some more fuel to stop detonation.

High throttle, high rpm, way rich, bogging/backfiring, waste of finite resources.

This was a real eye-opener: Lean here and way rich over there. No wonder the motor ran like a dog.

I created a set of correction values and things moved in the right direction. Then I created a second map and the motor ran very much better. Almost zero detonation (still waiting for a knock sensor) and screamed up to redline, yeaaaaah.

Still need some more fine tuning but looking good so far.

I conclude that significant engine mods (stroker, blah, blah) will cause the motor to run worse than stock because the ECM has no idea what is going on. In fact, engine management mods are just as important as selecting the right cam or priming the oil pump.

[rick]

I'm very curious to learn your cam specs... Is it a hopped up cam? Did it idle ok prior to remapping?

[aston]

I'm very curious to learn your cam specs... Is it a hopped up cam? Did it idle ok prior to remapping?

Basic engine specs:

http://www.golenengineservice.com/ht..._off-road.html

Idle is OK, starting is OK. I now have a knock sensor and associated electronics so I will try and create before and after graphs.

[FrankKoba]

I know it is 12 years old, so this post is a just a try. But because I am in same situation now with Golen 4.6 running crap in higher rpms and AFR values are like you posted above: did you ever managed to get this Golen engine running properly by using the SAFC-II?