Pre Computer Data Logging

[gilbogger]

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

[gone-ot]

...basically, none.

[t vago]

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.

[gilbogger]

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

[t vago]

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?

[dcb]

what sort of car do you have gil?

[gilbogger]

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.

[euromodder]

Originally Posted by gilbogger

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

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.

[ecoxantia]

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.

[fwhitlock]

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.