O2 Sensor Questions

[dieselgeek]

Re: O2 Sensor Questions

I generally don't think individual bank tuning is worthwhile on a V-engine, because the cylinders will vary more front-to-back then bank-to-bank. I either just put it in one bank or the other, then have someone whose good at plug reading make sure that there's no one or two cylinders significantly leaner than the others.

If you want to be precise, a bung in each individual header tube is the way to go, even if you only check them each one at a time.

[BOWTIE6872]

Re: O2 Sensor Questions

I generally don't think individual bank tuning is worthwhile on a V-engine, because the cylinders will vary more front-to-back then bank-to-bank. I either just put it in one bank or the other, then have someone whose good at plug reading make sure that there's no one or two cylinders significantly leaner than the others.

If you want to be precise, a bung in each individual header tube is the way to go, even if you only check them each one at a time.

no need on a carb..
a thermo gun reading from each header tube will tell you if one cyl is leaner or richer than the rest after you get the o2 reading in line bank to bank

[dieselgeek]

Re: O2 Sensor Questions

no need on a carb..
a thermo gun reading from each header tube will tell you if one cyl is leaner or richer than the rest after you get the o2 reading in line bank to bank

In my experience, the IR gun only helps tell you if that cylinder is firing or not. Unless you run zoomies with the exact same mass of metal on each cylinder, there's going to be differences between cylinders that make the "fine tuning" nearly impossible.

the bank-to-bank o@ reading is also going to be an "average" of that bank. If one cylinder has a misfire problem (or say, an exhaust valve not sealing up) then that whole bank is going to be out of whack if you're adjusting for the average...

but this is an interesting discussion. lots of people do it different ways. BlackoutSteve is somewhat anal about his combo, obviously, so I am interested in how he ends up setting it up.

[BOWTIE6872]

Re: O2 Sensor Questions

I have an engineering gun (one of works perks ;D)
that goes to the .00000 of a degree..
it's a beautifull thing

[SpiderGearsMan]

Re: O2 Sensor Questions

read the plugs like jack roush and robert yates
nascar - to their credit -ban any computer telemetry on race week
they set up the basic fuel curve on the dyno or test session at outlaw tracks with egt or wide band , but to get the jets just right on race day ... that is what happy hour is for

[dieselgeek]

Re: O2 Sensor Questions

I have an engineering gun (one of works perks ;D)
that goes to the .00000 of a degree..
it's a beautifull thing

how does it account for the differing thermodynamic behaviours of a set of headers? you're measuring the temperature of the header, and not the exhaust.

[BOWTIE6872]

Re: O2 Sensor Questions

I have an engineering gun (one of works perks ;D)
that goes to the .00000 of a degree..
it's a beautifull thing

how does it account for the differing thermodynamic behaviours of a set of headers? you're measuring the temperature of the header, and not the exhaust.

equal wall thickness.. on the test zoomies
it's amazing the quality stuff you get from surpliers, when you use an engineering firms addy ;D

[SpiderGearsMan]

Re: O2 Sensor Questions

latent heat
put it next to my temporary engineers license
use only in case of emergency

[CTX-SLPR]

Re: O2 Sensor Questions

I doubt anything that wasn't really bad would show up on a heat gun. What kind of EGT differences are we talking about here between optimal and off? If its under 10deg F there is no way you'd spot it with a IR thermometer. To make matters worse, you'd have to run the engine long enough for your pipes to reach a stable temp to really make a reading. I bet Dan could have pulled this off at the EPA but you aren't going to outside of a lab.

[BOWTIE6872]

Re: O2 Sensor Questions

I doubt anything that wasn't really bad would show up on a heat gun. What kind of EGT differences are we talking about here between optimal and off? If its under 10deg F there is no way you'd spot it with a IR thermometer. To make matters worse, you'd have to run the engine long enough for your pipes to reach a stable temp to really make a reading. I bet Dan could have pulled this off at the EPA but you aren't going to outside of a lab.

you read the exhause out of the test zommies..
not the pipe

[DanStokes]

Re: O2 Sensor Questions

Our aftertreatment development engines looked like they'd been attacked by a porcupine. Thermocouples sticking out all over the place, O2 bungs wherever there was room, etc. The engineers had a LOT of - um - "discussions" about where they should be placed. Often it came down to what was possible. Any engineer will tell you that you can't have too much data - which actually isn't true. Too much data can lead you to drawing conclusions that aren't real. A friend of mine likened it to "picking the flyshit out of the pepper". You'll waste a lot of time and pepper.

Back to Steve's situation - ideally, you would have a bung in each header pipe at the same distance from the head and move the sensor from cylinder to cylinder (or buy 8 sensors and enough readers to read 'em all at the same time). If one at a time, you would need to exactly replicate engine conditions between readings. In reality, probably not worth it. The real reason I suggested having one on each side is that you know where to start looking if you have to troubleshoot - which side has a leaky gasket, for example. Just speeds up the troubleshooting process if you have the gage anyhow.

Dan

[SpiderGearsMan]

Re: O2 Sensor Questions

E-xhausting
P-aychecks
A-nnually
thank you for destroying my country MR NIXON !!

[DanStokes]

Re: O2 Sensor Questions

Spidey - I wish I could have given you a tour while I was still working at the lab - I suspect you might have a different opinion. I'm not defending the policy people - they work out of DC and evidently on a different planet. But the folks at the lab, where the data is generated and sent to DC with appropriate explanations so they can at least possibly make good decisions (not saying that happens) - well, they're mostly good folks, and sharp in their fields. Like any data - idiots can misinterpret anything.

Still, if the good folks at the lab weren't supplying accurate info and insightful analysis, I shudder to think what would be going on. Remember, EPA works within the confines that Congress sets so if you don't like what's happening elect new Senators and Reps - they are the real decision makers (and no, not the Prez either - all he really has is the veto).

Dan

[BlackoutSteve]

Re: O2 Sensor Questions

Back to Steve's situation - ideally, you would have a bung in each header pipe at the same distance from the head and move the sensor from cylinder to cylinder (or buy 8 sensors and enough readers to read 'em all at the same time)..

Dan

For what it's worth, I am also installing 1/8"NPT bungs in each primary right at the header flange for thermocouples to measure temps. I have no equipment to to use or test with them, I just figured for the $3 each, they may come in useful when on a dyno in the future.

[SpiderGearsMan]

Re: O2 Sensor Questions

my conclsion is since the "ir is so much dirtier now " the epa failed
the price of lost revenue , lost wages and lost liberty has been overwhelming
epa obviously did nothing but add to the bloated unelected ass holes to tell us what to do
the diesel population of big ass trucks grew
not much done on those emissions until a few years ago
pollution was a hoax , just like global warming is now
because all of this overregulation wrecked our competitivness in the world