Cutting out at higher RPMs after big cam swap

[ZMAR]

I was stuck on putting a .515 lift cam in my 350. I put the bigger springs that Lunati suggested but when it gets to higher RPMs at the top of every gear it starts really cutting out. Not a huge motor head but kinda know my way around a little. I also just have center dump ram horns without any exhaust on right now. Could it be lack of back pressure? Also 600 cfm edelbrock could be lack of fuel i dont know. Any help i would really appreciate