I have a friend who wants to put on the LT4 intake manifold. Will the manifold work with the stock LT1 heads on his 96 SS?

 

nope

 

you need the lt4 heads to fit the intake.

 

You might want to do a search for posts by "Arnie".... he has posted some factual info on the LT4, which debunks a lot of the myths.... in summary, it won't fit without machine work to either the edge of the intake manifold, or the valve cover rail on the heads. And it isn't really any different from the LT1 in terms of port design, except that it has some extra meat in it to allow it to be ported to match the raised runners in the LT4 heads.

 

This should almost be a stickied topic .

Definitely search for 'arnie' & do some reading. I've posted pictures of what he's talking about as well a time or two .