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View Full Version : 02 's AND LT HEADER TUNING



tblu92
November 6th, 2009, 04:42 AM
I know this has been covered in some old posts but it seems it was never answered completely---
When installing LT headers and the 02 bung locations are futher back--How can you correct the PT closed loop fueling to compensate ?
My experience shows that typically the closed loop fuel will get richer with LT headers--I've seen about a wideband 14.0 average --- Can you fool the ECM by changing table B3601 (Stoich) from 14.68 to like 15.0 ?
OR should you change the swtiching points B4105 to correct the fuel back to 14.68 ? and should you add or subtract millivolts from the table ? By my way of thinking you should subtract from the switching points---but i tried that and have seen liitle change with the wideband
Or should you do both ?

Mr. P.
November 6th, 2009, 05:18 AM
I would also like to discuss this - from my reading here it is my understanding that relocating the O2s will affect their average switchpoints, and this needs to be adjusted... that's all I uncovered though.

Mr. P.

joecar
November 6th, 2009, 08:02 AM
Since they are now a further distance back, this also affects switch timing...

I want to know more.

tblu92
November 7th, 2009, 06:06 AM
I'll contact Jesse at Wait4me on Monday--he's been away and very busy lately and i didn't want to bother him---I'll let you know monday what he says--But I was hoping to get differnt opinions on this as I've tried several things and nothing seems to work 100%

cmitchell17
November 7th, 2009, 08:34 AM
x2, I tried to do the fake lean cruise with the switchpoints by moving them to a lower milivolt to make the ecm think rich so it pulls fuel.

But the headers I think are messing with it becuase its only adding fuel. It has also thrown some insuffecient switching codes and some other ones.

mr.prick
November 7th, 2009, 02:45 PM
What is the range your LTFTs, are the highly positive or negative?
Set the O2 switch points to 450mV and {B3601} to the fuel type's stoich
then make adjustments to VE/MAF.