Best kernel for nexus 7

[livisor]

What is the best kernel for nexus 7?I usually get around 7-8 hours from my stock tablet the way I use it but I'd like a safe overclock or something to make ppsspp a bit faster.I heard that some kernels trigger the 4 cores,can that be forced upon ppsspp who currently only uses 1 core?I would like to keep my 7 hours of battery with the new kernel.