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Old 05-06-2013, 04:20 PM   #18 (permalink)
bestclimb
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Join Date: Oct 2009
Location: South Central AK
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Quote:
Originally Posted by divedaddy03 View Post
Alright, here is where you are starting to talk over my head, not because I can't understand but because I haven't learned it and the "why" of it yet. So, you are saying that a scangauge measures the same way the computer in the call measures therefore it's just as inaccurate so...what's the point, right? I'm guessing that an MPGuino is a home built system using an Arduino board? I'm liking this idea....seriously! That said, can my 2005 know and monitor the fuel flow feed and return or do I need to then splice the fuel lines and install a flow sensor?
The scan gauge, ultra gauge and the like (I have an ultra gauge and like it for what it is) get air flow (and other) data from the car's computer from the diagnostic port. Run it though some math and spit out a fuel consumption number. When calibrated they can be pretty accurate but that calibration is only valid for that specific engine configuration.

I would say that a Scan/Ultra gauge would be good enough to test non engine related mods.

The MPguino is an arduino project that splices to the car's speed sensor and fuel injector signal wires.

Fuel injectors are either on or off. rate of flow x time the injector is on gives you the quantity of fuel injected.

It does not matter what sensors are telling the computer what, the MPguino just counts how much time the injectors are injecting.


Having used both ultra gauge and MPguino. I find the Ultra Gauge more useful for all sorts of car data and for eco driving it's inaccuracy is acceptable. The MPguino gives less information but the data it gives can be more accurate.



Quote:
Originally Posted by divedaddy03 View Post
Guys, I'm kinda rushing into it, I understand your skepticism. I'm a VERY methodical thinker and I REALLY, REALLY want to run these test before I modify. I want to do this the right way but I'm telling you, it's going to be two months until I can even think of buying anything more than $20 to test with so...I've got to think of my options. Why can't I monitor the fuel consumption along side of mileage on a large round trip route through the country and do this 3 times, then modify and do it all over again?
Can you insure that you will take every corner exactly the same, apply the exact same amount of brake, and do it in exactly the same amount of time, with the same average, max, minimum speeds, with exactly the same amount of acceleration and verify that environmental factors have not effected you data?
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The Following 3 Users Say Thank You to bestclimb For This Useful Post:
NachtRitter (05-06-2013), some_other_dave (05-06-2013), Xist (04-07-2021)