There is more than just porting the LT1 manifold to match the LT4 heads, as the ports do not line up.

 

The Trick Flow heads that I listed were LT1 style.

 

then what cam would u suggest is best ?

 

and on the ported intake already have 58mm intake and throttle body

 

Nice, the camshaft issue is for you to find out for yourself. Do you want a mild cam, a racing cam or a cam in the middle? What are you performance goals? You have to do the research for yourself on the camshaft and pick one that is best suited for your needs. Personally, I like the LT4 Hot Cam. It'll give you decent power gains for the price and you will still be able to pass emissions, this is why it is so popular. This link should help you on your research.
http://www.ls1tech.com/forums/lt1-lt...ion-guide.html

 

The LT4 Hot Cam kit is not worth the money.. If I were you I would take the money and take it too http://www.advancedinduction.com/AiProductsLT1.html look up the trick flow heads and the AI matched cam kit. Might be expensive, but worth every f**king penny. If you're looking at a complete engine rebuild, go for a 383 stroker kit from advanced induction, and the matched cam kit. Then throw a procharger on top and you'll be pushing some serious HP #'s (:

 

go here, lloyd can work magic with the heads and intake and his cams are just as good or better than any.
http://www.elliottsportworks.com/lt1.html