99 m6 ws6
94k miles

last year car was completely stock except for lid and weld in flowmaster. i did the following:

ls6 injectors (don't ask)
02 manifolds and added an ory (don't ask)
!air
!egr

now the car runs like **** and i lost 8 mpg.

idles and drives smooth, but obviously is missing power. i replaced the plugs/wires and installed new o2s.

trapped consistent 108-109 with best of 111 with just lid and muffler, now it traps 103-104 with an oddball 107..

anyone else experience this? hopefully it just needs a tune, i'm about ready to drive it off of a cliff. i just repaired a vacuum leak, but it doesn't seem to have affected the way the car runs at all. if anything it should've been stronger sucking in unmetered air and leaning out haha.

opinions?

 

i took my camaro apart and forgot to connect the MAF plug, ran like **** but still ran. plugged it back in and reset the PCM and it ran tons better

 

shouldn't be putting different sized injectors in without a tune to run them with.. get it tuned

 

 

clean ur MAF really good and tune that sob

 

the injector deal wasn't my idea, but i really wouldn't think swapping a 26lb injector for a 28.8? would make much of a difference.

i hadn't thought about the maf because i hadn't messed with it. worth a shot, i guess. i know it needs a tune, but the only people i trust to tune it won't spend the time to properly tune their own car(s) haha. oh well, it's about time for it to go into hibernation anyhow, maybe i'll invest some time in the spring.

 

PUT YOUR STOCK INJECTORS BACK ON NOW!!!! If I was upgradeing injectors unless they were free I would not go from a 26 to a 28 GM. Your not getting much. Now getting some 30Lb red tops or 42Lb green tops is a mod. The red tops flow about 36lbs at our fuel pressure. The green tops are good for alittle more than 42 as well at our fuel pressure. Never put a new injector in unless you are driving strait to your tuner or have the means to tune it when they are installed. Asking for trouble.