Are you using an UNI prefilter with H2W kit? If yes and you remove it, you'll have to change the main cause you're probably have somthing like 148-152.
Even with the CPR, i think 175-180 is way too lagre mostly cause of you're 2-1. When you Akra 2-1 do you talk about a complete Akra header 2-1 system or only a standard 2-1 with an Akra exhaust.
The standard 2-1 with an AKRA will be the most restrictive part of your system, not the air intake just like with the UNI prefilter. So maybe you'll have to use 155-160 or 160-165 main but probably not bugger than that. Somebody with a 2-1 and an OEM or DNA filter can lead you on that.
I think that most of your gain will be in the LOW to LOW MIDDLE rev. cause the back pressure in the exhaust will raise faster. You're gonna have to adjust IMS, stock IAJ and maybe clip on needle.
My 2 cents.