Do I need my intake ported to put on a 58 mm throttle body? If so where do I get it done and what kinda $ am I looking at? Thanks By the way 96 WS6 LT1

 

The stock LT1 intake manifold has 52mm openings. A 58mm TB will "work" without porting the intake, but it wouldn't make sense to do it that way. There is an adapter you can get that reduces from dual 58mm bores to 52mm, allowing smoother airflow, but once again, it's a poor substitute for a properly ported intake.

Any good machine shop could port that intake of yours.

 

got LE2 head/ cam /long tubes/ svo 30s/ spec4 and 410s on a ram air ws6.

 

I think you should be able to get the intake ported for less than a $100. I've seen that advertised somewhere but can't remember where. I'd just check with a local machine shop and see what their price is.