I "believe" your safe up to 19 psi. Get over 20 psi and you need to start upgrading. I'm good with my 178 pulley but when I add my 64.7 mm supercharger pulley on things get weird …. lean …. power DROPS at the top of 3rd. Not sure it's all fuel related but the AFR's lean out …. a lot. I also have a SL55 Pierburg fuel pump. It makes a difference if your on the edge and don't plan on more mods.

Les