Drag racers run C16. I can't afford to run 114 oct on a daily driver. I'm stuck with 91 oct. I have run 9:1, 8.3, and 7.4:1 on L motors. I have always run on the edge of detonation. While the 9:1 and 8.3:1 motors were fast they don't compare to the 7.4:1 motor. I can run 20 psi on pump. I just stacked the head gaskets on my 7MGTE motor to run more Boost. Stock is 8.5:1. With the long stroke it should have put me in the high 7's, real low 8's. I was at 17 psi until summer hit. I had to drop to 14 to keep it from knocking. I can now run 18 psi with no knock and it pulls harder than at 14psi. don't even notice the drop in compression. On my Toyota truck with the 3VZ V6 I could only run 12 psi with 1/2-3/4* retard(MSD) per PSI this is with 9:1. I stacked the HG's. I now run 17 psi with the same timing. I now need a stronger clutch as the stock one will not hold above 15 psi. I never had a clutch issue before, ever. Less compression and more psi has made more power in every engine I have had. This is not an opinion. The industry is selling to average Joe. He doesn't want a big laggy turbo that makes alot of power up top, he wants smooth power wich can be had with a small turbo and 7-10 psi and 8.5:1 reliably all day long. I want insane 2nd and 3rd gear roll on tire smoking burn outs on pump gas