Blowing Black Smoke On Boost

[Dose Pipe Sutututu]

1 minute ago, silviaz said:

Is that taking into account a properly tuned aftermarket ecu?

Dead stock tune, if you slap a wideband O2 on them, you'll see it hits high 10s.

Black smoke is fine, keeps things cool.

[silviaz]

Just now, Dose Pipe Sutututu said:

Dead stock tune, if you slap a wideband O2 on them, you'll see it hits high 10s.

Black smoke is fine, keeps things cool.

Ah right, now wondering whether I should waste money to get it tuned at all, probably a good idea I guess considering I don't have tuning papers from the last owner.

[Dose Pipe Sutututu]

Put a wideband O2 on your car, extremely valuable data.

Stops the guessing & assumptions.

[silviaz]

5 hours ago, GTSBoy said:

He's dumb.

The exact mixture you need to run will depend on the specific motor (some will need more fuel than others, because some are knock resistant and others like to knock), the fuel (if you were planning to run on 91 you would inevitably end up with lower lambdas than if you were planning to run on 100), the boost target, the state of modification of the engine (ie, has it got higher or lower compression than it did stock, has it got big cams causing you to bleed off effective compression outside of the cam's efficiency peak, etc etc???) and a number of other things. Having said that, for a given combination of the above it might be very sensible to be aiming for say, 11.5:1 in the middle of the torque peak. That is pretty rich, but not "very rich". Very rich is (obviously) richer than that. Stock Nissan ECUs liked to push the mixtures down to ~10:1 when they got run out of their comfort zone. That's defo black smoke territory, but still not smokescreen territory.

TLDR: he's dumb. The motor will be given what the motor wants, and that is not always "very rich".

Last question I had, can a super rich condition cause spark plugs to fail early? Say for example my mechanic says to change them every 10k but they fail at the 7k mark. From research I've done it seems to be the case, but then I assume it would depending on how much the car is overfueling? 

Edited April 15, 2024 by silviaz

[GTSBoy]

3 hours ago, silviaz said:

Last question I had, can a super rich condition cause spark plugs to fail early?

Foul. Not fail. Different things.

[Dose Pipe Sutututu]

You'll find motors that foul plugs quickly aren't because of running rich on boost but rather the rest of the MAP (vacuum to atmospheric) is garbage and/or the O2 feedback strategy is either disabled or is utter horse shit.

If you're not cruising and idling at stoich, but rather rich, you'll be going through spark plugs faster.

[silviaz]

3 hours ago, GTSBoy said:

Foul. Not fail. Different things.

Ah yep, foul I meant my bad.

[silviaz]

59 minutes ago, Dose Pipe Sutututu said:

You'll find motors that foul plugs quickly aren't because of running rich on boost but rather the rest of the MAP (vacuum to atmospheric) is garbage and/or the O2 feedback strategy is either disabled or is utter horse shit.

If you're not cruising and idling at stoich, but rather rich, you'll be going through spark plugs faster.

Ah right, interesting to know. I'll bring up the 02 wideband sensor up with my tuner as well.

[Kinkstaah]

Also you're fixated on the terminology here.

"Very rich" isn't a measurement. Very rich relative to what? It makes perfect sense for a tuner to say "On boost, you need to run very rich" if the Tuner is comparing "very rich" relative to Stoich, and they'd be accurate. 11.5 is very rich relative to 14.7.

Because anyone here knows that 14.7 on boost is not possible, terms like "Rich" and "Very Rich" and "Very Lean" and "Lean" typically revolve around/on top of the assumption that we're all running richer than stoich (14.7/lambda 1.0) to run any boost at all.

If you're talking boost, 13.5 on boost is very lean, but it's still richer than stoich. 10.0 is Very Rich, and Very Rich relative to stoich.

These terms are very stupid when not defined. Get the numbers, and I suspect this guy giving "bad advice" is actually giving reasonable advice, but you're fixated on words and definitions and stuff instead of getting the actual data. I reckon old mate is probably tuning to 11.8 or something on boost and all is well.

As dose said, fouling plugs is usually a symptom of too much fuel OFF heavy load. How would you know for sure? GET A WIDEBAND. It's near impossible for a tuner to properly dial in off-fuel loads while using a dyno. They get it roughly in the ballpark with an assumption that a guy with a tuned perfomance car will change their plugs every 5000km anyway, so the distinction between plugs fouling at 7000km instead of 10,000km is not a concern.

[silviaz]

31 minutes ago, Kinkstaah said:

Also you're fixated on the terminology here.

"Very rich" isn't a measurement. Very rich relative to what? It makes perfect sense for a tuner to say "On boost, you need to run very rich" if the Tuner is comparing "very rich" relative to Stoich, and they'd be accurate. 11.5 is very rich relative to 14.7.

Because anyone here knows that 14.7 on boost is not possible, terms like "Rich" and "Very Rich" and "Very Lean" and "Lean" typically revolve around/on top of the assumption that we're all running richer than stoich (14.7/lambda 1.0) to run any boost at all.

If you're talking boost, 13.5 on boost is very lean, but it's still richer than stoich. 10.0 is Very Rich, and Very Rich relative to stoich.

These terms are very stupid when not defined. Get the numbers, and I suspect this guy giving "bad advice" is actually giving reasonable advice, but you're fixated on words and definitions and stuff instead of getting the actual data. I reckon old mate is probably tuning to 11.8 or something on boost and all is well.

As dose said, fouling plugs is usually a symptom of too much fuel OFF heavy load. How would you know for sure? GET A WIDEBAND. It's near impossible for a tuner to properly dial in off-fuel loads while using a dyno. They get it roughly in the ballpark with an assumption that a guy with a tuned perfomance car will change their plugs every 5000km anyway, so the distinction between plugs fouling at 7000km instead of 10,000km is not a concern.

Ah right I think I get what you mean, cheers for the info. As mentioned yeah I'll bring up the wideband o2 sensor with my tuner and give an update from there.

[Watermouse]

On 15/4/2024 at 12:42 PM, Dose Pipe Sutututu said:

Put a wideband O2 on your car, extremely valuable data.

Stops the guessing & assumptions.

Is there a preference to brands for longevity and accuracy mate?

[Dose Pipe Sutututu]

Just now, Watermouse said:

Is there a preference to brands for longevity and accuracy mate?

Anything but Innovate, their heater circuit strategy is terrible so you end up torching wideband sensors (not too sure if this is still the case, but those MTX-L ones were notorious for eating sensors).

Or if you're already on the Haltech ecosystem, their canbus wideband kits are a no brainer. Sending data via canbus not a 0-5V range to the ECU not to mention if the sensor does die, just buy a Bosch LSU sensor and wire it back in, simples.

[Watermouse]

23 minutes ago, Dose Pipe Sutututu said:

Anything but Innovate, their heater circuit strategy is terrible so you end up torching wideband sensors (not too sure if this is still the case, but those MTX-L ones were notorious for eating sensors).

Or if you're already on the Haltech ecosystem, their canbus wideband kits are a no brainer. Sending data via canbus not a 0-5V range to the ECU not to mention if the sensor does die, just buy a Bosch LSU sensor and wire it back in, simples.

Cheers so much bro,

I asked cause I remembered there being one or two wide bands that kept failing

Edited April 16, 2024 by Watermouse

[Kinkstaah]

1 hour ago, Dose Pipe Sutututu said:

Anything but Innovate, their heater circuit strategy is terrible so you end up torching wideband sensors (not too sure if this is still the case, but those MTX-L ones were notorious for eating sensors).

Or if you're already on the Haltech ecosystem, their canbus wideband kits are a no brainer. Sending data via canbus not a 0-5V range to the ECU not to mention if the sensor does die, just buy a Bosch LSU sensor and wire it back in, simples.

I have an Innovate, but it's a LC-2. I want to update to a 4.9 sensor... but the 4.2 sensor refuses to die. So considering it's that old, and I'm still using the 4.2 sensor means that I think that not all Innovates are created equally, or sensor position matters a lot.

I have a brand new 4.9 sensor sitting in a box waiting for the day... but..

[Dose Pipe Sutututu]

One thing I do like about innovate is their ability to simulate a narrowband O2 output, great for deleting the OEM O2 and feeding that 0-1V simulated voltage back to the stock ECU.

Great for PowerFC users, Nistune users that do not have the luxury of ingesting wideband 02 data.

And before anyone says "yOu doN't nEEd O2 fEEdbACk iF yOUR tUNe is goOd" can GTFO.

[Kinkstaah]

I mean technically you don't. And you don't need a wideband if your tune is good.

But this is what I was getting at. It's really hard to tune something to that degree. Narrowbands are used to take a 'somewhat accurate map' into stoich, like a boost controller, and you're really just tuning how much 'work' it needs to do, with the aim of 'Better tune, Narrowband/Wideband has to compensate less'

But anyone who has ever done something like tuned one day, then DARED to drive on a day where it's 5 degrees colder/warmer, or in a slightly hillier region, or slightly higher altitude will look at their tune and

"If only there was some kind of device that could compensate on the fly and hit a target to account for...."

And now you know why Narrowbands, Widebands, and things like MAF's exist.

[Murray_Calavera]

I'd hate to think how many tables you'd need to have a constant perfect tune for all driving conditions without a wideband lol.