Barometric correction

For discussing how to choose sensors and create a wiring harness for all Bowling and Grippo versions of the MegaSquirt® EFI controller.
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efahl
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Post by efahl »

Mark,

That is correct. To tune the barometric correction you need to re-generate the baro-factor table, then re-assemble the code. (In case anyone is wondering, I don't recall of the top of my head how this would be done with MS-II.) An EasyTherm-like mechanism would be pretty simple to implement, the exact same table structure is used by all tables, and the correction factor seems like it should have the same characteristic curve as Bruce's above, but with a different coefficient for different engines.

Eric
efahl
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Posts: 102
Joined: Mon Feb 16, 2004 3:15 pm
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Post by efahl »

Lance,

Thanks, I thought it was something like that but didn't want to have to correct myself. :) The MS-II interface would make a nice one for EasyBaro...

Eric
Tortfeaser
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Joined: Tue May 11, 2004 6:24 pm
Location: Canberra, Australia.

Post by Tortfeaser »

Could this be the reason for my problem? See viewtopic.php?p=113302

Car (at home now) is now behaving normally, no problem. High compression (11.5:1), long duration cam, 4:1 exhaust with very little restriction (virtually unmuffled).

efahl wrote:
Erik88GT wrote:Can we say with certainty that no one has complained about the MS baro correction being wrong in actual usage?
Erik,

No, indeed we have had people that had problems with the current implementation. I recall one guy who tried to use it on a race car with an open exhaust and high CR, where the hard-coded correction factors were overcorrecting badly. I think that the ability to tune the algorithm (as in MS-II) is crucial to making it work in general, as the chamber size and exhaust plumbing should impact the required correction quite a bit.

Eric
Marc Kelly
MS'd AE82 Toyota Corolla shitta
MSnS-E'd Holden Camira rally car
In Canberra, Australia.
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