Well I really dont know if thats possible to get into the 13s Unless you open up hte block. Id say go get some head work done. Port your IM, Port the intake and exhaust ports. Do a 3 or 5 angle job. Clean up hte combustion chambers. If you got that along with the 75 shot you could make it. Get a VAFC too it would do you some justice and balance out all your air and fuel mods.