Hi,
In the real world a set of stock heads with a mild cam will make MORE power up to 3,800 rpm and ported stock heads are good to 4,200 rpm. Bigger heads will then flow better after that,but not by much will a mild cam. On the street I can't justify the cost of bigger heads when the stock heads are quicker to 60 mph. A small shot of NOS on a stock motor will wake it up better than big heads.
My 2 cents.
Perry.
