honestly
on a stock slanty,
in the rpm range that most slantys work in, the two barrel is just bragging rights. It was and remains, an economy measure.
I ran it cuz I had it, on the stock exhaust manifold, with the stock pipe but with a straight-thru performance muffler, and
you'll be happy to know, that my 9.5 true Scr 225, lost no power. Also, it gained none and nothing not even mpgs.
Well, it seemed to idle a lil nicer, lol.
The Super Six uses the same exhaust manifold as the one barrel setup, so there isn't a pressing need to make changes. Unless he wants to make improvements there too, of course.
There's more to the exhaust system than just the manifold. It starts right at the valve, and ends at or near, the back bumper, and includes the cam-timing.
