switching to a GM 3 bar, how badly will it throw off my tune

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Spawne32
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switching to a GM 3 bar, how badly will it throw off my tune

Post by Spawne32 »

Hey guys, im making the switch to a GM 3 bar map sensor i ordered from phearable.net. http://cgi.ebay.com/ebaymotors/_W0QQcmd ... MEWNXQ3aIT I read how to make the adjustment in ectune, change to the map sensor in the list that I am using, GM 3 bar, and hit save, and it will rescale the table. Im curious though, i see a couple different GM 3 bars in this drop down menu, i see a GM 3 Bar and a GM 3 Bar TEST, which one is the proper one to use? I notice that the KOEO voltage is permanently set in ectune, if it varys slightly from what I am actually reading, say i read 1.58 and ectune is set for 1.61, how much of a problem will that cause?

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JaredKaragen
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Post by JaredKaragen »

yep... ironically nothing follows the exact laws of common physics... that's where quantum physics fills in... your best bet is to start a new calibation, and copy/paste your old map(s) to an excel spreadsheet... then copy appropriate values to respective places, interpolate the rest of the cells, and smooth maps. Start car up and tune again from there =) just selecting map sensor... wont rebuild the tables completely the way you'd think. I always make a new calibration and go forward when a root piece of hardware has changed (map, injectors, non-honda ECT, etc). It makes you go though the steps again, but adjustments for the old parts in other places like trims not cause ghosts/bugs in the tune later. Use the standard sensor type. The test ones were for specific groups/tuners... others could fill in on that one.
95 Sol Si : D16z6 : TD04H-13C 74 Civic 1200 : 100% Stock

Spawne32
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Location: NJ

Post by Spawne32 »

blah from what im being told now the 3 bar map sensor will have shitty resolution for my application being low boost. Only reason i picked the 3 bar was it was actually cheaper then the 2 bar kits i was finding. Should i sell the 3 bar sensor and switch to a 2 bar for better resolution you think?

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Bindegal
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Post by Bindegal »

The resolution of the 3 bar is by itself fine, I´ve never had any issues with them. There is some nit-picking but nothing serious. For some, the accuracy between sensors isn´t spot on. This is to be expected at these aren´t motorsports parts. So, should you replace your 3-bar with another, seeminly identical one, you might need to verify AFR´s as they could be slightly different. Another little detail has to do with all ECU´s being slightly different also. You may not have noticed, but different (otherwise identical) ECU´s behave slightly differently, likely because of tolerance of the components.The difference is usually so slight that it is hard to measure it a standard car with stock injectors, stock MAP. But as you use the 3-bar and bigger injectors, the difference can be big enough to cause concern. A little tweak of the injector offset usually does it for me. /Allan
Regards, eCtune Team eCtune Authorized Tuner Location: Copenhagen, Denmark

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