Well i got a new tune from my tuner that was thrown around on here for a while and it worked good and fixed my idle problem but i still think my car is slower than before. i went from stage 2 with 42lbers to 2.7 pully and 60lbers. I used to be able to walk all over trailblazer ss from a roll and now i can bearly keep up! i really dont know what is going on with all these tunes and i have a feeling that the car is still really rich since my exhaust pipe has black soot all over it. And on top of that my car only boosts to 16psi at maximum rpm! i have had no trouble with this car until i pullied down and now i have more problems than ever. What are some tips that someone could give me to try to fix this???!

 

Find a better tuner? bad heat soak? good tune should have leaned out the car
should gain a little more boost with that 2.7

 

Well first off the boost at 16psi isn't really a "problem" since you are on a 3inch exhaust with port work, however I would still feel it should be higher but I dunno. If you want you can send me the tune file and I will take a look at it and give you/your tuner some pointers. Another thing with a 2.7 pulley is that your over spinning the blower and you have to worry about heat soaking. Your quickest pull/run/race is going to be your first, after that your going to heat soak. I HIGHLY recommend you get methanol injection and or some other cooling mods, or just simply going with a larger pulley. Most people think that smaller pulleys always means more power but that's just not the case. You need the supporting mods behind it to keep the iat2's down in order to run those extremely small pulleys. I have seen 2.9 pullied cars beat 2.5 pullied cars and vice versa, it really just all depends on the setups.

As I said though, either think about getting some cooling mods, methanol injection would be the most beneficial or have me take a look at your tune. As far as being rich, let me know what your eq ratio vs rpm is, along with your enrichment rate and I will let you know if you are running rich. A decent afr for a ss/sc is roughly 11.7. This is arguable and people have different opinions, however I consider 11.7 to be a safer more reliable afr then say 12.2 for a "max power" setup.

 

Yeah i fig he should be atleast 17psi but im only on gm full exhuast with gutted cat so i see 16 buuuut it is also has been very hot and humid lately in the area
x2 2.8 better as well with meth and dual pass setup

ids say silverbullet have zach maybe check your tune bc that seem like the problem