Thanks for your help,
This last season engine in the nova was a 383 and it was not so bad 7.44 sec with 3.73 gear. I owned and drived 5 big blocks and 2 355 in the past. As a new thrill I want to try high rpm small block. You've convinced to change cam style but i'll have to live (budget matter) with rhs heads because I already have them on my 383. Hoping that next summer engine will be a bit faster.