I installed my pacesetter Lt's and ORY earlier this week and daaaaaaaaamn what a difference in exhaust note and power it made, but I'm finding a few tweaks to my tune are going to be needed to compensate for the headers and LACK of cat converters. I'm tuning with Tunercat and have allready mod'd the basics < all rear o2 sensor DTC's and Cat overtemp enrich> now my question is how do i go about tuning the idle-low rpm area it seems to be running rich. Also I have noticed a slight "bog" along with a change in exhaust note<gets "raspier"> at and around 3000rpm, but no where else in the RPM range. O2s are reading around 880-900 in P.E. @ 3000rpms with around 24-25deg timing,no knock retard. Any help would be appreciated as i am a newb to tuning any thing other than stock trucks< ie no headers>ha

 

What year and engine?

 

oops thought i had a sig created ..... have to add that to the too do list 2006 ecsb 2wd 5.3T auto 3.23 Lt's, ORY, K&N 77 series intake, Magnaflow muffler, vette servos

 

If your still running the MAF, tweak the maf table by the trim percentages. The stickies uptop are for HPT but its all the same just looks different and named different.

 

thanks for the awesome write-up by the way 02sierra..... I've been using those since day one. It seems that I forgot to upload my modded VE table, seems the bog is gone and Ive got the richer idle figured out. Just a quick question.....how much total timing are you running @ WOT I'm seeing 25deg with NO KR I'm running 91 octane and was wondering how much farther i could go or would it not net an increase in power.