Hey guys,

I have a couple questions I need help with before getting my project on the road.

First off, the ECU

I have a T-5 R ECU in my 95 850 turbo (simple ECU swap done a year ago)
Its number is 0261203628
I need confirmation that this ECU WILL be able to supply fuel to 13 PSI when I install my boost controller.
Does anyone have this same ECU that could tell me?
If not, how can I find out how much fuel is supplied?
It is a heavy concern of mine to accidentally run lean and blow the engine.


Next, an a/f gauge

I have heard a terrible amount of bad stuff about narrowband a/f
It may all be true but is the gauge at least decent enough so that I can take an accurate reading to avoid rich and/or lean situations (low on $)
I have heard they are only effective when the throttle is wide open..well if in the case I am running lean, will running the throttle wide open for a couple minutes ruin the engine that fast?
Also one last question, Does anyone know which color wire (O2 sensor) to splice into on my 850?
I haven't checked yet but I don't have any idea where the front O2 sensor even is so any help is greatly appreciated!!!


Last, Boost controller

looking at this one, http://www.3barracing.com/product_7.htm
and the multi-system controller, http://www.3barracing.com/product_2.htm
*Would like to run stock sometimes for fuel conservation
Would set up look like my attached image?

Should my boost gauge be tee'd between the nipple from the turbo and the solenoid or the tree that comes stock on the 850? Or is either acceptable?


I apologize for throwing so many questions out at once but I thought it would be easier to just lay it all out on the table.

Any help is appreciated. I am a member of three forums and this is by far the best!!!

 

The ECU will deliever enough fuel at 13psi. The Fuel cutoff on the stock ECU's are ~15.5psi.

The narrow band gauges only let you know when the motor is around 14.7:1 (stoichiometric) closed-loop. It dosent tell you any real ratio numbers at WOT (open-loop).
Here is a good snip of the narrowband gauge:
Now since you will only be running 13psi. and the ECU can supply enough fuel till ~15.5psi, I think you be fine with just narrowband. (Moderator) Tech can show you his wiring for his narrowband gauge.

If you want to run at the stock setting to save fuel, Then I suggest you get the Multi-stage MBC from 3barracing.com. It will give you the option to set two boost settings. So the first setting could be your stock setting (~8psi), and then you can set the second stage to your performance setting (~13psi).

For hooking up the boost gauge...you can just tap into the stock gauge line, or you can use on of the open ports on you intake manifold. Tech can also show you how his is setup.

 

A Narrow band guage is basically useless on our cars. Mine is there just to fill a hole for now till I find something else to fill it.

Fuel cutoff is at 15.5 PSI.
I would set to about 13 max.

 

Well because money is a big issue right now, unfortunately I will not be able to upgrade to wideband.

That being said, is it a waste of my money to buy a narrowband a/f gauge? I really don't want to run at a higher boost with no idea of my a/f ratio.

Question for Tech: If you just have a narrowband a/f gauge right now, how can you feel reassured that you are running at the correct ratio?

Also, will my car (stock) be able to handle more fuel load (fuel filter, fuel pressure, fuel injectors). It is a concern of mine because this ECU isn't stock. My car, a '95 850 turbo running a T5-R ECU, was only meant to supply fuel at 8 PSI. Will it be able to up the fuel load if asked to by the ECU?

 

Yes it will be a waste of money buying a Narrow band. First of all it only reads in the rich side of the guage because our narrow band setup only reads from half a volt to one volt.
If it read 0-1 volt then it would work fine.

As for the setup First I am running a chipped ECU which is where I lay the money on the ratio that the ECU is doing its job.

Next the T5-R computer is setup to run more boost than 8 PSI stock. It is supposed to be atleast 10 PSI or a little more.

Even the stock ECU compensates good for the higher boost. Our stock setups tend to read richer from the factory.

I am running 14 PSI on the Yellow one and 12 to 13 PSI on the white one. The spark plugs are burning normal and nothing is out of the ordinary.

 

So do you think I can rely on the ECU in my car to do its job?

Maybe a dumb question, but will the car know to fire the sparks faster considering the pistons will be moving faster with more combustion?

Just a question of curiosity, what benefits do you see from your chipped ecu?

 

And, no disrespect, but if the narrowband a/f gauge doesn't help anything, why did you buy one?

 

The ecu should be able to handle it easy as long as you don't go to nuts adding other things before adding the wide band.

About the guage I got it REALLY cheap and plan on installing it later in another cars that it will work with. Like I stated above it is just a filler for now.

Eventually I need a wide band with the plans I have for the motor it will be a must to have.

With the ECU I see a little better fuel milage and with the stock setup it runs at about 12 PSI or so.

I have the Upsolute tune in mine.
You can check upsolute.com for a little more info on the tune. I think it is like $400.00 for the tune.

 

Did you notice a big difference between 8 and 12 PSI?

Do you think I could take it to a volvo dealership, have them run a dyno and make sure the a/f ratio is ok? Or is there literally no way to measure without a wideband 02 sensor?

 

A decent dyno shop should be able to monitor the wideband while running it to see if it leans out to much during the run.

Yes I noticed a big difference.

 

Well Tech I'm all excited to do this conversion but also scared considering it is my noly car to get me from point a to point b. If I ruin this car I've got a pretty big hole to dig myself out of. To increase your boost, does the ipd ecu tune do it or do you have a boost controller?

 

Most tunes up the boost just from the tune. IPD is a decent one but a little expensive but kind of worth it.

The site should tell you the boost change with the ECU as well.

 

I'm not looking into buying an ipd ECU

I'm confused here because I thought the manual boost controllers main purpose is to override the wastegate actuator.

How can a tuned ECU override the actuator on the wastegate. Isn't the actuator a little device that says, "if more than 8 pounds of force hits me, I'm going to open and dump the excess pressure to regulate the 8PSI."

 

Yes The MBC allows more boost to hit the wastegate, because you preload the spring in the MBC, which then takes more pressure to push the ball out of the way inside the MBC, which then goes to the wastgate, which will open at the stock psi setting.

The 850s have EBC (electronic boost controllers) or TCV (turbo controll valve), which is controlled by the ECU. An ECU flash or Chips has a custom map for both fuel and ignition, as well as uping the boost. The chips or ecu flash can do this, becuase the stock EBC goes through the ECU.

 

So with my upgraded T5-R ecu am I running 10 PSI?

 

If 10psi is the stock setting on the T5-R, then yes. The only way you will really know is by hooking up an aftermarket boost gauge, assuming you haven't yet.

 

True, I haven't wired one yet.

Is the EGT gauge a legit alternative to the a/f gauge? Seeing as I can't afford a wideband and the narrowband doesn't work.

I hear a lot of debate whether an a/f or EGT is better. Which is in your opinion?

 

1. Narrowband waste of time and money. If your tight on money why waste what you do have for something that doesn't work. Well it works, but it doesn't tell you anything important.

2. Wideband is the way to go even if they are expensive.

3. EGT isn't close to A/F from what I know. Exhaust Gas Temperature, that is what EGT means. It measures temps not A/F. And for an EGT gauge your looking at $100+, unless you buy used which I wouldn't.

4. Hook up a real boost gauge before you run a MBC. You will want to know your before and after boost readings trust me. Also an ECU upgrade from IPD, RICA, Upsolute, SpeedTuning USA, BSR is a much better option then a MBC. Even if they cost more, with at least IPD and RICA your looking at a great tune that more then likely wont make you run RICH or LEAN. Upsolute and SpeedTuning USA make some people run RICH.

 

The tunes are like $700.
I'm looking at a budget of about $300 so they are totally out of the question.

I think, but I'm not sure, that the exhaust gases will be hotter when running rich or lean which in effect has the same function as an a/f. Someone please confirm or deny this.

A $100+ EGT gauge is much more in my range than a $300-$400 wideband conversion.

If I can use EGT I would like to. Can anyone tell me if EGT is an acceptable alternative?

 

Yes the EGT will show hotter temps for both lean and rich conditions, but that still wont tell you the ratio (11.1:1 or 17.1:1) which is what you are looking for.

You have a budget of $300....Create a turbobricks.com account, and PM Fredrik (Frpe82). He works for and sells Hi-Tuning.com chips (Hituning-USA.com) in Sweden. The chips are sold in group buy, and it would cost you $360 shipped to your door if you live in USA. EU areas have to add VAT (25% tax).

Edit:/ I bought the AEM UEGO controller (wideband) for $222 shipped to my door.