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Fuel table y axis

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Running a vipec v88 plugin on an rb26. Just having a read an noticed the help function mentions changing the y axis on the fuel map from map to tps on turbo engines with individual throttle bodies. 

Seeming as the rb26 has this setup I was just wondering whether it's advisable to do this as the base map provided has it set to map currently.

and if it is advisable how would you go about setting the scaling on it or would you just click "init" and leave it at that?


cheers dan

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Generally the best result is obtained using TPS for the main fuel axis. You would initially just set with the "init" values which will give 10% steps 0-100%

Then have the open loop AFR table on and set to MGP of its axis this will give boost correction.


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Hi turbodailydan,

is this the same ECU and vehicle you are having the MAP sensor issues on.

Blowing black smoke running super rich etc.

If so then this is your problem, these engines have a very weak vacuum signal from what little plenum/vacuum chamber they have behind the throttle blades.

If you have your fuel table set to MAP on they axis it will read very close to 100 kpa at idle, this will make the ecu think it is under load and therefore run on the 100 kpa fuel row, causing excessively rich mixtures.

Most people make the mistake of hooking up the MAP sensor hose the  FPR hose port with a T piece.

I have even seen one setup where the inlet plenum was drilled into and had a vacuum hose barb fitted, this will only read boost as the vacuum signal comes from behind the butterflies.

I have attached 2 screen shot of how to set up a multi throttle low vacuum sourced engine.

1. is a basic set up

2. Is a more advanced set up incorporating a 4D fuel table that in boost is tuned as an extra % on top of the fuel cell number in the main fuel table which uses TPS as it's load reference .

This table will only allow an extra 60% of fuel to your table.

If you find this is not enough,you can adjust the FUEL MASTER VALUE or if you have a good fuel pump with plenty of flow crank the fuel pressure up.

See how you go.





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