You say you configure your wideband to output xx volts at xx A/F, how does someone do that and what help is that if the PCM is taking basic +/- inputs to adjust trim?

I assume all the wideband is ever going to do for me is validate my tune. And because I only bought the standard HP Tuner suite all I’m going to be able to do is validate A/F visually unless your saying I can throw a wideband in place of a narrowband and read volt output thru my tuning software.

Again keep in mind I’m a noob here and this is not a max effort build (I have one of those) nor is it a MPG build (I’ll never have one of those)... it’s a street car that I plan to drive a bunch an beat on every now and then.

As I get better I’ll likely buy HP tuner Pro so I can see real time A/F and more and make adjustments for a max effort build... My Nitrous SBC will eventually need a complete makeover and if this turbo LS1 stuff goes as planned then I’m likely going to replace the SBC but not until I get a handle on basic tuning.

Again this build will be very simple
Turbo
Cam
Injectors
Springs
Trunnion
And a good fuel system

If I can make this work I can step it up from there. AFR is just one of the components I feel is critical and I honestly was unclear of how/what the narrowband sensors informed the ECU of.

 

Narrowband / closed loop:
You can't use a narrowband to tune the engine in terms of performance very well, barely. Some (few) might argue about that but it would be like somebody arguing that a jackhammer could be used as a can-opener. Sure, it might work, but it also might splatter your delicious food all over the road. You can use a narrowb to tune an engine like the factory does- make it hover around 14.7:1 for normal "cruise" situations (generally > 50KPA most engines) and inch by inch move the VE map to avoid a large fuel trim. But that is it. 14.7:1 is useless after about 20-40% throttle, usually once you pass around 50KPA, the narrowb is practically USELESS.

I Don't like to chase fuel trims personally in closed loop because my combo is always changing (who is ever happy with their setup for long?) So once you realize if you are the kind of person who likes to constantly change their combo for more more more all the time, it would not make any sense to run around chasing fuel trims. You could spend several hours or even days chasing the trims, then next week do something minor to the combo and have to start all over. The fuel trims are more for sheep to drive a car once it is finished; for example if you are through with the vehicle, no more work on it, its driving fine and you are ready to sell it; That is when I would dial in the final fuel trims for the combo, enable "sheep closed loop" for the new owner and hand it over. But it isn't something that as a tuner/owner you should normally be interested in, unless you are looking to drive it like a "normal car" (take the wideband out of the car and pretend its stock when finished).

HPtunerpro:
You can use an EGR input (0-5v) to read the wideband, you don't necessarily need pro version. Although pro makes it far easier to setup.


Works of caution and how to treat the in-car wideband:
First, understand the wideband can read WRONG. It is rare, but, positioning, temperature, quality of exhaust gas/fuel type, will affect the sensor reading. As the sensor gets warmer it will generally read richer, slightly at first, but if it gets too hot it will be wayyyy off. I had a wideband once tell me 11.5:1 when it was really 15.5:1. I caught it on the dyno but it was too late, toasted all piston rings on my engine that day. With good tuning you can avoid engine damage; but the high temperature caused by running lean can cause other issues, such as piston rings which lose their tension.



The proper way to "tune using in-car wideband" First, I check my air-mass calculations. I find out how much air mass is going into the engine. There are simple equations (i.e. [CID*rpm/3456] = [cfm * 0.069 * pressure ratio] = lb/min @ typical temperature
And there are better equations, the point is, you find out how much air the engine uses.
HPtuner you might notice has it's own air mass calculation, it uses this for a variety of things and is very important to line up properly if you can, otherwise you have to change ALL kinds of things, like trans-shift pressures for example.

Then once we have air mass, we do a "magnitude check" I will do one:
355cid engine X 6000rpm / 3456 = 616CFM @ 100%VE * .069 (turbo temp constant) * 1 (N/A engine) = 42.5 lb/min or 425 horsepower.
Magnitude check: Does a 5.7L engine with 100% VE at 6000rpm able to produce approx 425 horsepower? I think that sounds right.

-You need to understand volumetric efficiency and 4-stroke engine theory to some extent
Now that we have an air mass calculation which makes sense, I can convert my mass of air per unit time into mass of fuel per unit time, by using the air fuel ratio I intend to run.
So how much fuel in lb/hr or cc/min do we need to hold 12:1 a/f ratio at 42.5lb/min? I will let you figure that one out, just remember to divide it among the number of injectors on the engine.


At the end what we get is an injector duty cycle. We assume the fuel pressure doesn't drop of course, and that the injectors actually flow their advertised numbers, stuff like that. The point here is to know in advance, before you even build the engine or buy the injectors or turbo, how much power the engine will make and how much fuel it will need when it does so. That way when you finally get the whole project together you should already have the proper amount of fuel in the fuel throttle regions of your map, since you already calculated all of that. Go slightly richer than you need to of course at first, THEN you start using the wideband. Notice we did a LOT of wide open throttle tuning before we even touched the wideband. It should NEVER be used to "dial in a/f ratio". Instead, always do the reverse: YOU calculate the air mass and airfuel ratios first, input those numbers which "make sense", and then VERIFY it with the wideband. You should be VERY close, and if so, it will give you confidence that the wideband is reading correctly. If you hadn't done those previous calculations and completely trusted the wideband in the car for tuning, it could very well be your first and last mistake.


Few more notes:
In car wideband is not nearly as good as a dyno-meter's wideband setup. I forget why, but I think the wideband on the dyno uses some kind of special filter to keep it cleaner. In any case, the message here is to NEVER fully tune a road-vehicle using in-car wideband without something to back it up. For most of us, plugs plugs plugs is what you will hear about. Pull the plugs after a run, or whenever you feel like IMO, and look that the color of each and condition of each is UNIFORM, and that they look GOOD (not melted or damaged obv). You can read more about 'plug tuning' if you want there are all kinds of ways to use plugs for tuning. The second way is the DYNOMETER's wideband. Take your car to a GOOD dyno (I always go the same place where I know they maintain the wideband) and compare in-car with dyno wideband. The dyno's wideband in the tailpipe is generally reading .2 to .5 leaner. So if the in-car wideband says 11.5 and the dyno's wideband say 11.8 this is normal and actually very GOOD to see how accurate your in-car sensor is. This is what you want. I wait until the dyno-wideband comparison is available before doing my "final tuning" of a/f. For example lets say the in-car wideband says 11.5 but I am really 12.5. Well, this could be acceptable in some combos, I might get lucky. But if I say "Hmm the engine would run better at 12:1" and lean it out so the in-car WB says 12:1 now I am really at 13:1 and the engine is in danger without me even knowing it.

note about temp
last, temperature is a part of tuning. Temp will affect fuel quality behavior (whether 93 octane explode violently or not for example). For ex. the EGT is very important, integral part of tuning, you don't always need to know it (from a gauge), but you do need to be aware of it. As temp increases many things change. An engine sitting at idle for an hour may not be as hot internally as the same engine running wide open throttle for 1 minute. It depends on how many joules/second the engine is producing (J/s = watts, a form of work measurement, like horsepower). As power increases, J/s increases (like having a brighter lightbulb) and so more energy is thrown into the exhaust system (imagine standing near a 60W and then a 500W lightbulb), the temp will rise until it balances with the rate of temp removal. Some engines produce enough power that they will NEVER achieve a steady state, and temp will keep increasing until something melts or explodes. This might be a 1-race only type of deal, where you stage a car with big power and make a pass, at the end of the pass it is so hot it needs to cool down before another run. If you took that car to a highway and started making back-to-back passes something will melt or catch fire, unless it was setup for such activities. This is all about temp; if you are aware of the rising temp, and peak temps the engine is making, it is essential for making tuning decisions. Also many turbo manufacturers have max inlet turbine temps they recommend (Borg Warner for example I think is around 1250*F) so temp is a parts-longevity concern on top of safety issue. A boat is a good example of an engine which might work at max output for a lengthy period of time; if you spend some time examining how LS-boat engine projects are setup it is very useful and will teach you quite a bit about engines also.

 

I'm and old skool plug whisper, come with the territory when you spray.

I also build cars around having enough fuel, better safe than sorry so I'm following you there. But I used a much simpler calculation found on the Holley site, it all started with what HP you wanted to make:
Optimal GPH = (Max. HP x BSFC) / 6
Optimal LPH = (Max. HP x BSFC) / 1.585

For nitrous I found using .6 for BSFC (brake specific fuel consumption) was about right for GEN 1 engines.
And of course all this did was size the pump, it was up to me to tune correctly by reading the plugs while messing with jets and timing until the MPH was there and the plugs looked good... then I bought an AFR gauge and you know what, nothing changed. I didn't trust the thing, read fat and plugs were light tan.... Nitrous will do that to a sensor in the header collector, called too much heat as you noted. I shielded the sensor in the collector by stepping it out and it got better but I still think it is off.

So anyway....

For the mass fuel calc, not the best at math where in the calc do I sub the AF? The calculated LB I assume is sub'd for RPM....???

And how exactly do I wire the WB into the EGR, and more importantly how do I read it?

 

BTW, still a fan of AFR gauges. Still a good tool to help tune.

 

Hi EP I use the NTK Hot Start Sensor (four wire) with my ECU-882C 100% of engine operation time as common.

My EGO sensor object calibration Map is based on RPM/MAP with sensor output voltage of .1-1.2 Volts as common, locked in Firmware.
When engine testing/calibration was done BOTH Bench/Rolling Road I used the UEGO AMP MADE by NGK. (1986)
My reads are equal between BOTH sensor styles EGO/UEGO.
I manufacture a UEGO AMP for the Bosch 4.2 sensor, CAN 2.0B interface AND the Objects to allow for calibration Voltage inputs High/Low.
This was also tested, same pipe/same time/two sensors, using the NGK AFRM with equal reads found.

This TYPE of testing REQUIRED an EGT read/report.

THIS thread states little about the importance of the Exhaust Gas Tumperature with respect to the tune.

Lance