if the 02 sensors are in closed loop most of the time on a 08 why add a fuelpack when you add a high flow air system and slipons.i ask this because i added a bigsucker,fuelpack and se slipons and it does not run better than stock, but it is much cooler. i am thinking about unhooking the fuelpack to see if it will pep back up. could somebody explain 08 s and the 02 sensors

 

I might have mentioned some of that in discussion within https://www.hdforums.com/m_3533110/printable.htm as well as links within that thread.

I am not a fan of the Fuelpak, but have no direct experience with it. My opinion is based mainly on their tight-lipped treatment of how to adjust it and lack of information from them regarding what/how it does its thing.

 

Well generally you do not build up an engine for closed loop operation. Rather you do it for wide open throttle and high rpms. The high flow ac gets more air into the cylinder. So without adding more fuel as well you run leaner. I believe that will run cooler because the heat peaks at 14.6 afr. Leaner is less power though. Generally you do not put on performance parts for less power.

 

From what I have investigated on a fuel pack, simply put,&nbsp\\;it reprocess the signal sent to the injectors getting its information from tps and temperature, basically tells the injectors to stay open a bit longer.