Retrofit fuel economy gauge?
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Retrofit fuel economy gauge?
I first thought adding a flow sensor to the carb fuel feed using my iPhone GPS output would do the trick but finding a flow sensor is hard!
Anybody got any ideas?
Thanks,
James
Posted
Local Hero
The fuel economy meter was only on C formel E and later GTI with the MFA. It doesn't measure fuel consumption though. It measures everything else and uses a lookup table to determine the assumed mpg. So it won't work if the car's out-of-tune or has been modified affecting the engine, and it certainly won't work if you transfer it from one car to another with a different engine.
In theory its possible to measure the fuel flow on a carb car, but in practice it won't be accurate enough, no car manufacturer managed to incorporate a mpg meter on a carb car which actually measured mpg.
With the advent of electronic fuel injection and electronic speedos, it became possible to properly measure it.
Vacuum gauge does a vaguely similar thing, but in some situations won't reflect better economy.
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Local Hero
Driving with a vacuum guage for fuel efficiency - YouTube
Mk1 Golf floor mats - for tin top and cabriolet - Zero7796 17298Five
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GavB95 said
I think the only option is to fit a vacuum gauge and then monitor the gauge readings to your fuel economy to give an idea of scale.
Driving with a vacuum guage for fuel efficiency - YouTube
Hardly the most accurate tho.
I'll have to keep searching for a flow meter and then find some way of getting the GPS speed data and the flow data into a computer of some sort.
Anybody know of any flow meters that would be suitable?!
Posted
Old Timer
work out mpg when you refuel.
sorry couldnt resist
1988 1.8 carb Golf Clipper
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Local Hero
Concorde_Rules said
GavB95 said
I think the only option is to fit a vacuum gauge and then monitor the gauge readings to your fuel economy to give an idea of scale.
Driving with a vacuum guage for fuel efficiency - YouTube
Hardly the most accurate tho.
I'll have to keep searching for a flow meter and then find some way of getting the GPS speed data and the flow data into a computer of some sort.
Anybody know of any flow meters that would be suitable?!
I admire your enthusiasm but you've hit a stumbling block at step 1, and you've come onto a Mk1 Golf forum to ask for a fuel flow meter for a carb. Not really Mk1 related, and probably better answered with a simple google search. Even if you find one, what are you going to do next? Interface it to a computer and write some kind of short program to constantly work out the mpg? Design an electronic circuit to do this?
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paul_c said
Concorde_Rules said
GavB95 said
I think the only option is to fit a vacuum gauge and then monitor the gauge readings to your fuel economy to give an idea of scale.
Driving with a vacuum guage for fuel efficiency - YouTube
Hardly the most accurate tho.
I'll have to keep searching for a flow meter and then find some way of getting the GPS speed data and the flow data into a computer of some sort.
Anybody know of any flow meters that would be suitable?!
I admire your enthusiasm but you've hit a stumbling block at step 1, and you've come onto a Mk1 Golf forum to ask for a fuel flow meter for a carb. Not really Mk1 related, and probably better answered with a simple google search. Even if you find one, what are you going to do next? Interface it to a computer and write some kind of short program to constantly work out the mpg? Design an electronic circuit to do this?
The idea with coming here was because someone might have had the same idea as me
Been googling for quite a while and all i've really come across is a marine flow meter which might do the job.
And yes, that is the basic idea.
I don't plan to keep the system in the car, it's just so I can work out what the MPG is in each gear at varying speeds and leave it at that.
More of a interesting summer project to increase my electronics/coding knowledge than anything really serious.
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Local Hero
Local Hero
Carbs4ever said
Just got the car taxed there last week but with work etc I haven't been able to get much work done on it. With baby and all never got looking at it much since I tucked it up for winter… but the sun has returned so better get it ready again for the road!
I got a Zeitronix system for it from the wife for Christmas which was greatso I have been fitting it when I get the chance - almost finished….
This is the system - measures all sorts from EGT - AFR to air temp/oil temp / revs etc even has alarm for which can be used to alert to low oil pressure or exhaust gasses going too high - and it can also trigger a relay to either switch something on or off! Quare and nifty! It also plots all this information on the laptop and records hours of information - will be great for checking fuelling across the rev range
I opted for Lamda/AFR - fuel pressure - air temperature and exhaust gas temperature and the alarm/trigger box and bought it through Chris at EFI parts in England.
First job was removing exhaust system to get lambda probe boss welded in - note mahoosive drill bit - da had this one hiding away
Then four branch needed drilled and welded on no.1 primary for the Exhuast Temp probe boss - which was also tigged by big Glen in GM Tyres - he's a useful character
He even made it look nice….
Then exhaust back in place with probes installed and I figured rather than have that mass of cable running under the car I could coil it up under the centre console and it would be away from heat etc - so just made a small cut in the gear stick plate to allow cable to lay flat on top of the tunnel.
Then everyone's favourite - the wiring! Made a loom up to go in the engine bay to feed the air temp sensor which will be mounted in the air box and the fuel pressure sender - EGT wire is kept separate to avoid any interference. Routed all this out of site and through a bung in the bulkhead then under carpet to center console
And you know me - if it can be polished it will be polished - so buffed up the wee adapter for the fuel pressure sensor - it's basically a 3.5 bar boost sensor which you can programme the zeitronix to read psi and therefore read fluid pressures too - and installed it just after the Filter King regulator.
In place
Then soldered on plugs to the ends of each wire feeding the zeitronix unit so that it could be removed if necessary without any hassle and got my switched live and system earth sorted and gave it a try! Woopee it worked first time - that was a pic before connecting the lamda and switching on fuel pump - but everything is working!!! Great having real time fuel pressure read outs etc - finally will be able to see if the pump struggles on WOT.
So now just tidying the wiring under the centre console and will get a wee place for the usb connecter to attach for handy plotting on the lap top - also think I will not mount the lcd screen and will keep it free on the lead so it can sit anywhere when driving….
http://www.vwgolfmk1.org.uk/modules.php?name=Forums&file=viewtopic&t=781&postdays=0&postorder=asc&start=315
http://www.zeitronix.com/Products/Products.htm
8)
Mk1 Golf floor mats - for tin top and cabriolet - Zero7796 17298Five
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Local Hero
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VW GOLF MK5 / VW GOLF MK1 Owner
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All they really teach you is how to be very light with the throttle to keep high vacuum and thus good economy. If your a smooth driver you find you drive that way anyway.
All a flow meter will get you would be a high reading when WOT and a low reading going down hill. unless you have a computer program working out and average of fuel flow/distance covered to give a average mpg it would be useless. It would take sensors and computers. so basically the same work as just converting to FI.
for cheap economy kicks just get a 10 quid vintage vac gauge of ebay.
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Old Timer
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Retrofit fuel economy gauge?
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Local Hero
I have seen Vacuum gauges, upshift light, computer displays and all the like, but on long trips the Cruise control works.
Rabbiting Starts, and WOT are not conducive to better mileage.
Besides in mt Golf Dieseling days JAck Rabbit starts and WOT only resulted in the release of BLACK smoke in the face of the person behind me…
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