4.5 max got richer afr after 3" catback and y pipe
4.5 max got richer afr after 3" catback and y pipe
Guys,
Ok making this thread out of curiosity bc i didnt expect the results.. after some research makes some sense but just incase the maxima gurus have more input
My 3.5 swapped hybrid maxima was previously tunned with a cold air (in fener) a vis block off plate, ebay y pipe using 2" primaries to a 2.25" tube, to a greddy sp2 2.5 inch catback and no cat conv. tuned to about 12.8s
after installing a custom non equal length y pipe using 2.25 primaries into a 3" pipe, and then a custom 3 inch catback also without a cat conv. the car was in the 11s afrs. The safc2 needed more correction to get it back into the 12.7s.
research shows, that the more flow, could cause the ecu to see higher maf values and overcompensate dpending on predetermined wot values. anyone else has had this happen please chime in incase i need to look at other issues that may be going on.
Ok making this thread out of curiosity bc i didnt expect the results.. after some research makes some sense but just incase the maxima gurus have more input
My 3.5 swapped hybrid maxima was previously tunned with a cold air (in fener) a vis block off plate, ebay y pipe using 2" primaries to a 2.25" tube, to a greddy sp2 2.5 inch catback and no cat conv. tuned to about 12.8s
after installing a custom non equal length y pipe using 2.25 primaries into a 3" pipe, and then a custom 3 inch catback also without a cat conv. the car was in the 11s afrs. The safc2 needed more correction to get it back into the 12.7s.
research shows, that the more flow, could cause the ecu to see higher maf values and overcompensate dpending on predetermined wot values. anyone else has had this happen please chime in incase i need to look at other issues that may be going on.
Last edited by aic96max; Feb 28, 2011 at 09:50 PM.
Guys,
Ok making this thread out of curiosity bc i didnt expect the results.. after some research makes some sense but just incase the maxima gurus have more input
My 3.5 swapped hybrid maxima was previously tunned with a cold air (in fener) a vis block off plate, ebay y pipe using 2" primaries to a 2.25" tube, to a greddy sp2 2.5 inch catback and no cat conv. tuned to about 12.8s
after installing a custom non equal length y pipe using 2.25 primaries into a 3" pipe, and then a custom 3 inch catback also without a cat conv. the car was in the 11s afrs. The safc2 needed more correction to get it back into the 12.7s.
research shows, that the more flow, could cause the ecu to see higher maf values and overcompensate dpending on predetermined wot values. anyone else has had this happen please chime in incase i need to look at other issues that may be going on.
Ok making this thread out of curiosity bc i didnt expect the results.. after some research makes some sense but just incase the maxima gurus have more input
My 3.5 swapped hybrid maxima was previously tunned with a cold air (in fener) a vis block off plate, ebay y pipe using 2" primaries to a 2.25" tube, to a greddy sp2 2.5 inch catback and no cat conv. tuned to about 12.8s
after installing a custom non equal length y pipe using 2.25 primaries into a 3" pipe, and then a custom 3 inch catback also without a cat conv. the car was in the 11s afrs. The safc2 needed more correction to get it back into the 12.7s.
research shows, that the more flow, could cause the ecu to see higher maf values and overcompensate dpending on predetermined wot values. anyone else has had this happen please chime in incase i need to look at other issues that may be going on.
Thread
Thread Starter
Forum
Replies
Last Post
shilov
4th Generation Maxima (1995-1999)
13
Feb 19, 2024 09:40 PM
lrb6805
4th Generation Maxima (1995-1999)
7
Sep 17, 2015 04:49 PM
