Fuel flow sensor needed for older vehicle

[CollieJim]

Hi
Good forum - lots of good stuff here.

I would like to build a vehicle computer for my old Suzuki. Normally aspirated, carby type.
For that I need a fuel flow sensor.
My searches so far have turned up some but all have been either very expensive or are designed to fit in proprietary systems.
Where might I look for one.

Thanks
Jim

[haklesup]

you aint kidding. Even on eBay you're talking $200 for an appropriate component. I know they are somewhat complex parts but I guess the relaibility and safety testing requirements drive the price way up. Typical customers seem to be pilots and boaters

http://www.mglavionics.com/FuelFlowSensor.pdf
I found this one on ebay for $195 and when you look at the construction you'ss see its probably a $10 cost of goods

If you're looking to do it on the cheap. You're going to have to harvest one from a wreck at a junk yard and then characterize and calibrate it manually. Get one from a car and at least you know its the right rate to be useful.

I think most flow sensors are just like encoders, they emit so many pulses per gallon. So calibration would consist of pouring a known volume through it and counting the pulses. Like most automotive components, its probably 12V compatible and consisting in this case of some switch contacts on a rotary encoder.

A device with resistive or proportional voltage would be measuring fuel flow rate not just the flow and that would be a lot harder to work with.