I have always heard of doing this and a supposed gain? I guess some aluminum is added to the port near the injector but for what purpose and what is the expected result? exactly where is the aluminum added?

I would LOVE to see pics of this or detailed info on how to do this

 

I've wondered the same. I think some even use some type of epoxy or something similar. Someone get in here and straiten us out. Pics would help too!

 

My guess is any gain from doing so would be in low end torque by constricting the charge flow and increasing the charge velocity. The cylinders would fill more efficiently at low RPM, but flow would be choked at high RPM. It would probably also result in lower top end HP.

 

I had this done to my LT4 intake. I don’t have any pictures of the before and after. I had a friend of mine TIG weld material on the outside of the ports, starting just above the injector, going up about 2 inches, and the with of the pair of ports. The purpose of this is for when the runners are ported. There isn’t enough material there to fully port the runner without breaking through. Without the welding, you can only port the runners so far, leaving what most call the "ski jump" in the runner. Someone had posted before and after pics of this, hopefully they can chime in here and maybe post them. As far as gains, I really wouldn’t know what it would net someone on their application. If you can have it done, I would say its worthwhile, and can only help. The real problem with the factory intake is the lack of plenum volume.

Nick

 

Here's a picture of what Nick is talking about.