I'd be tempted to explain that by inaccuracies in the sensor or voltage levels on the wire. But https://en.wikipedia.org/wiki/Atmospheric_pressure tells me that average sea-level atmospheric pressure is actually 101.3kpa which is very close to what your seeing. Then the data is also crammed in to a single byte packet in the log with a range of 0-256. So that also affects your accuracy slightly when you start caring about parts of 1 kpa.
Weather has a lot to do with it too but im not really sure how much difference it makes. Watch out for the high and low pressure systems crossing your area on the weather reports on tv and then key on your car and see how much difference they make? The car map might not have enough resolution to pick it, but it could be interesting.
my ride vt ecotec
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antus
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Re: my ride vt ecotec
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
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vt3.8lt
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Re: my ride vt ecotec
Yeah im on the coast at sea level aswell so it should be pretty accurate
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VL400
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Re: my ride vt ecotec
I thought both 2 and 3 bar ADX files had boost PSI but was only the 2 bar. Have updated the 11P zip so if you grab that can see in your logs exactly what boost you are running (it accounts for the baro pressure).
Resolution of MAP, 1 bar = 0.37 kPa, 2 bar = 0.78kPa, 3 bar = 1.22kPa. That is not accuracy, it will be worse than that. Its just what can be resolved with an 8bit analog to digital converter that the ECU has.
Resolution of MAP, 1 bar = 0.37 kPa, 2 bar = 0.78kPa, 3 bar = 1.22kPa. That is not accuracy, it will be worse than that. Its just what can be resolved with an 8bit analog to digital converter that the ECU has.
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vt3.8lt
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Re: my ride vt ecotec
oh ok cool i wasnt aware of the i got a copy of the 104 that its running now ill have a look and see if i can work out how to bring it up
The answer is always... boost!
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vt3.8lt
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Re: my ride vt ecotec
Hey guys i found out how to get it to log boost perrure thanks for the tip got another question but the vacume still hasnt come up and you have to use the throttle to get this thing to start up by a fair bit of input ive been around sparyin looking for a vacume leak but im un able to find one is there anything you guys can think of i should look at that may have an affect on this vacume at idle doesnt seem to have improved much even with the extra timing
The answer is always... boost!
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Dylan
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Re: my ride vt ecotec
If you need throttle to start it reduce your cranking bpw. Usually needs modifying after different injectors have been fitted or a big cam will need that reduced too.
As for the vacuum what does it idle at? A decent cam could idle as low as 80kpa I've had one on my own car idle at 85kpa. But a cam like that would be bad for a boosted engine.
As for the vacuum what does it idle at? A decent cam could idle as low as 80kpa I've had one on my own car idle at 85kpa. But a cam like that would be bad for a boosted engine.
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vt3.8lt
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Re: my ride vt ecotec
Ok cool ill look into that i thought the throttle may have something to do with a cranking fuel issue
Yeah it idles around 70-80 kpa and has to have the butterfly screwed all the way in to idle by its self witch is y i thought it may have a vacume leak but i cant find one
Yeah it idles around 70-80 kpa and has to have the butterfly screwed all the way in to idle by its self witch is y i thought it may have a vacume leak but i cant find one
The answer is always... boost!
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Dylan
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Re: my ride vt ecotec
My car that idled at 85kpa had the butterfly stoo screw right in with a afr of 14:1 and 0 steps at a warm idle. Started great with the right cranking1puse width. It was just trial end error to get that right.
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vt3.8lt
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Re: my ride vt ecotec
Ok so its not just me it just seemed strange to me thanks man ill look into that cranking to se if i can get her to fire up easier but she idles around 14.5 afr at around 70 ish kpa
The answer is always... boost!
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Dylan
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Re: my ride vt ecotec
That's not bad. What's the cam specs?