I have a set of 98 LS1 ported Mac headers with blockoff plates and modified Y pipe. Can be used on newer LS1's without EGR tubes.

Both headers have been ported to remove all weld build up. The head connections and collector were ground. The ball connections have been ground to open them to at least the ID of the 2 1/2" pipe.

The Y pipe is an off road that had Bullet mufflers. They were removed and pipes spliced in. The spliced pipes are crimped with muffler clamps and not welded together. It worked like this for me so I never had it welded. I have also ground the passenger side hanger off the pipe as it was not needed. There is a Flowmaster collector welded into the Y pipe. It is a dual 2 1/2 x 3 1/2" collector. I ran this into my 3 1/2 cutout.

My car ran an 11.206 @ 118.22 mph with these headers.

I am including the ported headers, ported/modified Y pipe and both bullets for $350.00 Local only, Come and get them!

Email me at larry98@alltel.net for pics.