over 3 yrs ago guys running a 181 pulley were maxing out the fuel pump and running lean. oem pulley gets you 14 psi, 181 bumps 20 psi. with out a proper tune and fuel you will pop that motor if you keep running wot. its well known the 181 , 185 pulleys need to be tuned before running wot and tuning without enough fuel wont work. ask xray about the tuning session in atl in 09. 181 maxed out and no tuning done could fix it. had to design robs adj fuel kit to get him right. others just stuck a sl55 fuel pump in and they are fine.

if i have said it once i have said a thousand times, if your gonna mod you gotta log!! 50$ for a O2 bung and a simple wideband will save you a ton of heartache