Pre Computer Data Logging
 

What sort of options are there for data logging an engine that has no computer?

...basically, none.

It depends on how fancy you want to do it.

You can get flow meters for your gasoline line, have an O2 sensor installed in your exhaust, or fit a mass airflow meter in your intake. That's not terribly involved, but it will involve buying these things, and installing them.

Other options include putting your car on a chassis dyno, or using a 4-gas analyzer. Those, of course, are also costly.

what about "simple" stuff,...temperature, voltage/current, rpm etc?

You could get temperature senders for measuring temperatures, but you'll have to calibrate your data logging equipment to work with these things.

You'll also want to rig up some sort of tachometer, driven inductively from the cylinder #1 spark plug wire. That'll give you engine speed.

Voltage is simple enough to directly record, but current is a little tricky. What sort of current are you measuring?

what sort of car do you have gil?

it's a 1989 Jeep (AMC) Grand Wagoneer thats been modified and stripped down a bit,...it's a 4x4, V8 (360 5.9L), 4514lbs curb, 18mpg from the factory partly because of it's really steep axel gearing (2.73:1). I'm getting about 21mpg highway with an ac delete, maybe 250lbs weight savings and some good quality aftermarket upgrades (HEI ignition/dist, 4bbl carb, intake, cam, headers/exhaust, ford taurus efan). There are still a few low hanging fruit things to be done,...I think I'll end up around 23-24mpg with this current setup.

i have some pretty big things I would like to try next, the challenges of a large vehicle, and the fact that i'm insistent that it's ability to perform work (4x4 and tow capabilities in particular) be maintained if not improved, means this project is somewhat unique, which creates even more need for decent data logging...the data just doesn't exist yet, not to do what I think can be done.

ideally, here's the sort of things i would like to know.

- tach log: an additional baseline measurement to go with distance and time. the engine revolutions will also give the numbers to help isolate the effects of pulse and glide.

- temp log: engine temp of course, ambient temperature too. but what would be really valuable would be adding a couple other temperature readings from other points in the cooling system. for example, i'm interested in scheming up an intelligent electric water pump that operates at 2 or maybe 3 stages, and maybe get that water pump to work more intelligently with the radiator efan...a good "map" of the cooling system in real-time (not 24/7 death valley mode) could find some pretty substantial efficiencies.

i wouldn't necessarily require the logger to control these functions, unless such a wonder device happens to exist. for example, with the electric pumps/fans i would setup a set of thermostat probes to actually trigger the relay, but I need the data to know where those points should be.

- volts/current: this is a big one since I'm seriously considering a deep cycle battery bank to be able to run the alternator only when necessary or when braking augmented with a fairly decent size PV array on the roof (large vehicles do come with some gifts in hand). logging electricity consumption becomes really important...having one system be able log a dozen points in detail would be nice, voltage, draw and total Whr.

- time: simple yeah, except the need would be more for logging duty cycle where that data would be otherwise impossible to get. a half dozen different duty cycle graphs in one spot would be nice for testing results.

- fuel: accurate fuel usage,...this might be more challenging than I think because of the carb fuel return line,...especially when running leaner than normal....i assume you'd have to measure the return as well and take the difference.

tall order, doing all of these measurements one by one will be a complete pain first of all, and not as accurate just as importantly. really want to bring as much hard science to this project as possible and would like to provide my results as a case study to anyone who's interested.

at the risk of being laughed off the board on my first post,...40mpg is the goal i say out loud,...50mpg is what keeps me up at night...i plan to drive around the country working towards that,...logging thousands of real world miles in as much detail as possible...measuring what works and how it can work better and sharing the results with anyone who wants it.

The 4x4 crowd needs to meet the ecomodding crowd, who needs to meet the fabricating geniuses, the junk yard artists, the electronic guys, the back yard scientists and the shade tree mechanics. The RV/boat guys know their batteries, and the old school engine guys don't need a manual to make their iron purr, and the racing guys know how to measure and solar guys know their stuff too. It's a game of inches in sparsely (and sometimes misleadingly) documented territory.

I just see some interesting possibilities when all of this knowledge can be combined with real thought, real creativity and a complete disregard for convention. We're smarter together, and I'm out to prove that.

I realize this was a little long winded, and I hope it didn't come across preaching to the choir. Just wanted to introduce myself and what I'm passionate about. I am in over my head,...this idea seems like lunacy even to me...but I am deep in it's grip and helpless to ignore it.

So in short, I'm Mike and I'm going to turn my big ass vehicle into a long-term, open-book case study, logging miles all over the country, improving along the way with anyone who wants to give expertise or time or setup an A/B/A test with an idea they had.

Christ, it doesn't sound any saner that way.

An industrial flow meter ?

Filling up frequently - if you don't need to make a detour to go to your favourite fuel station.


As for logging:
Back in the old days, they filmed gauges to log data. ;)

If you could have a laptop in the car then logging temperatures and voltages is pretty straightforward. Companies like picolog do some interesting stuff to make that a turnkey operation.

Then there's Arduino single chip computers, recent ones can store lots of data. You'd need a lot of time and patience to go that route I expect.

1984 Wagoneer Has 3.88 gears. Still 2bbl Motorcraft 2150 Carb. 3in. exhaust and Magnaflow muffler (too loud unfortunately), did a TFI coil conversion (Jeep trick) and Transgo stage 2 shift kit went from 11-12 to 15 mpg. Did you go for the Edelbrock carb and manifold? Like you, I am very interested in mileage while retaining 4WD and towing. I did use a Globtec GPS logger for a while - not enough info. Will be installing a tachometer and Vacuum gauge soon.

50... OK.... well you can see what it takes to get 50 by looking at the vehicles here that do it. Pretty sure there are no V8 4x4s in that group...

When I bought it, it was with an Edlebrock intake and a Holly Pro-Jection 2D fuel injection kit. I switched to an Edlebrock carb, found the Holly 2D to be a bit of a pain and couldn't afford one of the nicer fuel injection kits.

I replaced my whole ignition system with a Malloy HEI dist, which I've been quite pleased with. It's tight next to the power steering pump is my only "negative" comment.

I'm getting 21mpg highway, but I have 2.73:1 gears.

I've sketched out what it would take to data log with an Arduino using custom sensors. I've never played with an Arduino but I have a background in web programming, it would be fairly simple to setup an Arduino based SD card logger for $300-$400 or so.

This expensive hurdle is fuel metering with a carb. With fuel injection it's much easier to solve with known injector rates. Fuel flow meters are expensive ($1,800ea Edlebrock to $400ea for marine grade) and I understand them to have accuracy issues by their very design. For a carb setup, two meters are necessary for send and return lines.

Taking total fuel consumption would provide aggregate fuel information, but would fall short of showing actual usage at a moment of interest.

Apparently some early fuel injected Ford/Mercury's had flow meters on them, the decked out versions had a digital real-time MPG readout that got data from a flowmeter, I believe it was an aftermarket part installed at the factory, vs a Ford part number. I'm going to keep my eyes open for them during junkyard visits, but they we not common.

I think the most reliable setup would be flowmeters who's data is checked and then adjusted by the manual tank-to-tank logging. It would still be a tad fuzzy but should close enough to be reasonable, especially with enough data samples to make the comparison meaningful.

The rest of the logging is pretty straightforward, an Arduino GPS module could be tied in,...a two axis gyroscope could indicate hills and turns, tach output for engine rpm, magnetic sensors for driveshaft and axle rpm and then some voltage reading for temperature sensors etc. Then take manual environment readings to append to the digital log.

Would be an interesting project.

"50... OK.... well you can see what it takes to get 50 by looking at the vehicles here that do it. Pretty sure there are no V8 4x4s in that group..."

I think you mean there are no V8 4x4s in that group...yet.

I mean there are no V8 4x4s in the group... ever.

Use the aero calculator to estimate what mods it would take.

all over but the crying, huh? christ...

thanks for setting me straight.

I am always here to help! :thumbup:

I did a search for every Jeep in the EM garage.

Highest one was mpd8488's '97 XJ at 28.51mpg, but I consider that bogus as there is only one entry in the fuel log.

Next up is dadag's '07 Patriot with 25.29 mpg. It's 4x4 but it's only a 4 banger too, so that doesn't count. BUT if it did count, you'd have to DOUBLE it's efficiency.

There are no Grand Wagoneers in the garage with fuel logs.

I did a search for engines 4.8l and up. There were zero entries that met the V8 4x4 criteria that even hit 20 mpg for a lifetime average. There were a few entries above 20 mpg that were only single-entry logs- disqualified. There were a few 2x4s but only "jeeterstruck", a '94 Dodge SLT 5.2l a/t, averages 23.06 mpg. And there's three or so diesels that are above 20.

Good luck to ya.

this really seems to be bugging you. your "help" is overwhelming.

correct, 50mpg is a lofty goal
correct, 50mpg is more than double 18mpg
correct, there isn't really a history of ecomodding a Grand Wagoneer

what can I say, I like my bourbon spicy. no one is making you drink.

I would like to put VW in it's place by modding my Tempo to get 300 mpg.

Doesn't mean it's going to happen. Doesn't mean it'll get anywhere close. Not even with professional help (for the CAR)!

defying physics is a rather narrow assessment of a problem and possible solutions.

but if that's the brush you like to paint with,...then I think I would be best served by spending my resources and time into developing a time machine that will somehow defy physics enough to get me out of this conversation with you.

Nah- think of it as a challenge. Won't it be awesome to create your 50 mpg V8 4x4 and rub my nose in it? Why, I'll even grovel before you if you get 40. Carry on.

Gil, you should peruse some of Big Daves work.
Details: The Red Baron - 2000 Ford F-350 XLT Fuel Economy - EcoModder.com

He has an '00 F-350 XLT 7.3L (4x2) that he has nursed 28mpg out of, and is fairly exacting in his methods as well.


Edit: also note that you can get a clone usb arduino for like $20, it has 6 onboard a/d converters so you can monitor 6 analog signals and send them out the usb port with minimal external circuitry, then figure out the readings on a laptop or ??? And you can get a map sensor from the boneyard for peanuts, stick a thermistor in the airstream and you can compute air mass w/rpm.

There are so many data loggers on the market there are only two reasons to reinvent the wheel. The first is because you really want to make your own, the other is because you have special needs that can't be met with an off the shelf system.

For your needs the products developed for race cars are probably best suited because the developers had mad many of the signals you want to collect in mind. The products aimed at the weekend auto cross and other non professional race teams will be the lowest cost. There is a lot of stuff out there which means competition, which means you can buy it for cheaper then you can develop it, so you may as well save yourself hundreds of hours of development time.

Do some hunting around on the internet, a Google search for "race data logger" turned up some good prospects. Be creative with your search string to narrow the search. Look carefully at specifications. You want something that collects for a long period of time so you can collect for a whole tank rather then just one race. You probably want a lower sampling rate than most race teams are collecting. Also look at the support tools, a good package will provide some analyses tools or at least make files that import to your favorite spread sheet.

Mike

why do u need a logger? just calculate every tank, its what i do