So, I have a custom exhaust, HFC, straight thru 2 1/2 in. piping, no resonator and muffler. Between 3k-4k rpm at half throttle there is a lil hiccup going on, meaning a lil lag. At full throttle no problem, anyone have any ideas whats going on and how to fix?

 

maybe your car is not properly warmed up. i feel it sometimes on my si too when my car is not yet warmed up and its completely stock right now

 

what intake? this is due to not having a cat which gives the secondary 02 sensor a bad reading which in turn sends a bad reading to the ecu. the ecu will try to adjust but ends up bogging.

 

I have a k&n intake and have a universal magna flow cc. So what ur saying is to put the oem cc back on?

 

yeah if you put the stock cat back on it will take that hiccup away

 

i drove with my dcrh for like 2 weeks with the cel on before i got my defouler and it never hiccuped

 

ok thanks. Can you also weld up a cc with a race header, just farther down on the piping?

 

depends on the header, the new skunk2 header, its going to have to be farther down. for those with a flex pipe, u can just cut and weld a flange