You might be able to go with something like thiswhat is the biggest cam i can run on stock 307 valve springs?
i just want the thump.whats the smallest cam i can go with and still get the rough idle?how hard is it to change valve springs?
thats y i asked him what his plans were for the cam, i went through the same thing man read my 350 one i took all the info given and made the decision not to, after u read it all u can see why i made my mind upDidn't we just go through this in at least two other threads? I don't suppose you did any searching or read other threads.
stock 400 wants choppy cam
Stock 350 wants choppy cam
stock 307 wants choppy cam
Maybe elblako91 can post a picture of changing valve springs since he's doing just that in the thread I recommended you read.