Tim Burgess: an idea >>
 

I had an idea for something that should be made, and could probably be marketable.

How about something that plugs inline to the fuel level sender that will (algorithmically?) correct the fuel gauge (eg: to show half a tank when you actually have 7.75 gallons in the tank). I'm sure it's a matter of curving the resistance slope to compensate for the v-shape of the tank.

Just an idea... let me know what you think..

yeah i hate how almost all GM gas gauges change greatly all the time and it appears you less than you do usually. F**d cars dont have this problem!! It's a good idea.

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84 Firebird w/ T/A gfx, 350 4bbl (LM1), Non-leaking T-Tops (new rubber all around), Auto, Working headlights (new parts), K&N, 180* thermostat, ram-air hood scoop, flowmaster muffler (yuk), Accel cap & rotor, MSD Super Conductor Wires. Soon: new gray interior, SFCs, poly bushings, WS6 sway bars & springs.

Good idea - the gauge reads higher than the level of the fuel actually is, so a log amp would probably do the trick for compensation.

Tim

I was just thinking of redoing the face of the fuel guage. Y'know, changing the location of 3/4, 1/2, 1/4, etc. It shouldn't be toooooo hard to stencil onto a piece of plastic. I'll fool with it and let you guys know... Or else why not look for one of the f*rd guages that accurately show fuel that was mated to a tank around our capacity. I'm sure there was something around that size then...

My Cadillac has a 25-gallon tank, but when it's on "E" and the "low fuel" light is on...it only takes 13 gallons to fill up. How stupid.

I agree with all of you on this. My fuel gauge NEVER reads acurately. it will veary by atleast a quarter tank! Also, when I go into a haaaaard corner, the car starves for fuel. I have an 89. I heard that 91-92 had swinging fuel pick-ups like the 1LE package. TRUTH?

I havent verified the swinging fuel pickup, but the baffles in the tank exist on the later thirdgens (90-92 or 91-92 only, all models). When I pulled my 91 Z28 and my dad's 92 RS's fuel tanks down, they both have the baffles around the pump to stop the fuel starvation.

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West Coast GM Shootout 2001!
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Im running a Cyberdyne digital fuel gauge (set @ 15 gal) and it's VERY accurate. As for the fuel slosh, I've got a Comp Engineering sump welded on with a slightly smaller shaped opening in the tank (acting as a baffle),the only problem with it is you've gotta run an external pump.

I'm going to be selling the tank within the next few months (going for a Fuel Safe) if anyone is interested.

the swinging pickup was available in the early 90's I think, but if I remember correctly it was only an IROC option but I have read about this before.

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'87 Monte Carlo SS,with '89 IROC 350,700 trans, blew up 3.73 posi stuck with crappy 2.73's neeed gears! hooker headers, flow's 2 1/2" exhaust true dualls, recently installed a set of alum vette heads 58cc, new cam for a paxton, waiting on paxton till I can find a good rearend. So if anyone knows where a buick GN 8.5" rear is let me know.

Can anyone comment on whether the inaccuracy is caused by the gauge or the sending unit? Maybe the reason for the huge area below e on the gauge is because the float arm (im assuming this is how its setup) bottoms out before the bottom of the tank. I know in my s-10 I've for a 19 gallon tank, and even after driving on E for a while the most i've ever put in is about 14 gallons.

On the other hand, if the float arm has the full throw but there is just a problem with the range of the gauge or the linearity, it shouldnt be too hard for someone knowledgable enough to design a circuit to compensate. Of course it would have to be adjustable so it could be used on different applications.

I think it's the sender. When the tank is full the float is all the way up, but you have to burn off probably around 4 gallons before it actually starts dropping, and when it starts dropping it really moves PDQ! It probably dosn't even come close to hitting the bottom of the tank either... so it's probably "registering" from 75% to 25% (guess) of the total fuel.

The reason was in my original post...
The fuel tank is sort of V-shaped. At the top, there's a large volume of fuel and as you go down, the tank becomes narrower so from a 1-diminsional perspective (up/down) it seems to be consumed faster.

And as for the baffle and pickup design differences, I don't know anything about that, but I do know if both my RS and my IROC are on "E", I can wing the IROC around a corner without regard to fuel starvation, but the same turn would cut out the RS. Maybe it's a difference between the tanks, a difference between the TBI/TPI and/or pumps, the years of the cars or any combination thereof, but the difference is definitely there.