Wideband O2 Question

[Newold1]

What program or system will you be reading the wideband /AFR readings with?

To properly tune you really need to have actual loads on the engine and not just running the engine up at various rpms sitting. Obviously a chassis dyno is the best but it can also be done in the car under driving and accelerating conditions as long as you can data log the resulting AFRs.

Put a 24" collector extension pipe on for the readings, that's a must for decent accuracy.

This will take some time so have him drive so when you get stopped by that officer, he can sign for the ticket !! HA

[nickpohlaandp]

What program or system will you be reading the wideband /AFR readings with?

.....

This will take some time so have him drive so when you get stopped by that officer, he can sign for the ticket !! HA

You answered your own question. The program I'm using is called "the street".

Edit: for this car I won't be using datalogging software. Since I'll be the passenger I'm just going to be watching the AFR's on the gauge as I have him hold the rpm steady. I'll make notes.

I've tuned a lot of cars, mainly fuel injection, using datalogging and street driving under different conditions. The main thing for me when I do this is to find a day when the temperature will remain fairly consistent and have a nice, flat, long road. When I lived back in GA that was not an issue. Out here in Louisiana I haven't needed to tune any fuel injection systems yet, but when I do, it'll be a different story because I can pretty much get a consistent temperature/weather conditions, but finding a long, flat, straight road where I can datalog without risking getting a super-speeder ticket, well that's a different story. Generally what I like to do is get a base tune written that will allow the car to be "drivable" so I can get it out on the road. Once I get to that point I will start datalogs at about 1500 rpm, going up in 500 rpm increments, holding each rpm for about 5-10 seconds (this depends on how long the road is). After each datalog I'll extrapolate the data, make changes to the tune, load the new tune, and repeat. I keep doing this until everything seems to be working nicely, then it's on to the WOT pulls. Those are a lot easier to tune.

[Newold1]

Sounds like you have it well under control. If the car is driven for any lengthy street driving he'll be installing some kind of muffler system in short order unless he, the neighbors and the police have a serious hearing deficiency! Might as you already know, will need some tune tweeking if he installs a muffler and exhaust system beyond the headers. Have fun, by some earplugs for the tune time.

[nickpohlaandp]

...Have fun, by some earplugs for the tune time.

I'm a helicopter inspector by day, I always have hearing protection, lol. It's just a run of the mill 429 with a slightly more aggressive cam than stock, a Weiand dual plane, and Holley carb, but I plan on it being obnoxious. I have a two year old too, so rest assured, once it's fired it'll be going back to his house asap. No need to ruin my little dudes hearing too. 18 years around helicopters and hot rods has already done a number on mine.

[MadBill]

...Have fun, by some earplugs for the tune time.

I'm a helicopter inspector by day, I always have hearing protection, lol. It's just a run of the mill 429 with a slightly more aggressive cam than stock, a Weiand dual plane, and Holley carb, but I plan on it being obnoxious. I have a two year old too, so rest assured, once it's fired it'll be going back to his house asap. No need to ruin my little dudes hearing too. 18 years around helicopters and hot rods has already done a number on mine.

A friend of mine who was an Engineer with Bell Helicopter for a number of years told me that insiders refer to them as "flying fatigue testers"

[nickpohlaandp]

A friend of mine who was an Engineer with Bell Helicopter for a number of years told me that insiders refer to them as "flying fatigue testers"

LOL, here's the shirt I wore to work today.

[turbo2256b]

Many builds will even run best with a collector extension. Many times in the 18" range give or take. Would get a long extension use some cheep paint to run a stripe down the extension then cut the pipe were it burns the paint first.

I've read about this in the past. What initially spurred my interest is when I was doing dome day-dreaming web-surfing looking at high dollar stuff that I'll never need and I noticed a lot of high end headers come with quick-interchange collectors (lengths, shapes, etc.). Pretty cool stuff once I started reading about it. This is so NOT the case with this car though. This car is just really a "daily driver" cool old 429 Torino. Personally I think it'll run better with a full exhaust, but if he wants to run it with open headers, then he can run it with open headers. I give him two days tops before he gets a ticket for it though.

Often did as stated above then welded a bolt on flange (actually both ends if needed) then a bolt on reducer to the extension for the rest of the exhaust. which he may decide to do after being pulled over.

[MadBill]

A friend of mine who was an Engineer with Bell Helicopter for a number of years told me that insiders refer to them as "flying fatigue testers"

LOL, here's the shirt I wore to work today.

Perfect!

[Belgian1979]

I remember some engineering saying that fatique can be calculated... Yep, that's reassuring.

[nickpohlaandp]

I remember some engineering saying that fatique can be calculated... Yep, that's reassuring.

There's a mathematical formula for damn near everything. In helicopters there are just WAY too many variables to pinpoint a reasonable "failure" life limit. I don't know how true it is, but I've heard one of the manufacturers of the larger aircraft we operate will stress test a part in a test cell to X amount of hours or cycles. When the part breaks they take that value, cut it in half, and that's how they come up with the life limit they use to get it FAA or EASA certified.

[AMXstocker1]

This topic made me think of something. could a header crank case evac system effect o2 readings?

[nickpohlaandp]

This topic made me think of something. could a header crank case evac system effect o2 readings?

I never really thought of that, but I suppose it could if the evac into the exhaust was before the O2 sensor. Generally you want to mount the o2 sensor as close to the engine as possible, so theoretically you would have the evac after the o2 sensor, in which case I don't think it would matter.

[MadBill]

Most evac fittings I've seen are in roughly the same location as O2 sensors are usually. Since the evacuated gases are a mixture of exhaust and possibly some fresh air from external leaks, I'd say you should definitely compare readings with/without the evac working and to play it safe, tune without.

[AMXstocker1]

we have a header-vac system and it is right about where i'd put an o2 sensor except that its pointed at an angle to flow with the exhaust.

[David Redszus]

Most evac fittings I've seen are in roughly the same location as O2 sensors are usually. Since the evacuated gases are a mixture of exhaust and possibly some fresh air from external leaks, I'd say you should definitely compare readings with/without the evac working and to play it safe, tune without.

X2.
In addition, OX2 sensors are temperature sensitive and if evac gases affect temp it will alter O2.
Use a sensor with an internal thermocouple.