Looking to have my exhaust re-done soon, getting away from dual tailpipes that came with my truck. Going back to a single 3" tailpipe in the stock location.

My local muffler shop wants to remove the Y-pipe all together and run two 2.5" pipes off my cats into a dual in/single out muffler. He claims better exhaust scavenging, makes more torque. I know the Magnaflow Y-pipe is the popular choice for replacing the choked up factory unit.

I don't know if I believe it all. I am not an expert. I do know some trucks come from the factory this way, mainly big block GM stuff. Let me know what you think.

 

Either the Maggy "Y" or his idea will free up the exhaust a good bit over that sh*tty stock "Y" pipe.

But your exhaust guy doesn't know his a$$ from a hole in the ground. Scavenging will be unaffected as long as all the gases are mixing at the stock manifold. Headers would be needed. Also, the gains you'll see from freeing up the exhaust will show up in the mid to high RPM range. If anything you'll lose just a tad of low end torque as the torque curve will move up the RPM band slightly.

Still a good idea to ditch the factory "Y", but the gains are gonna be exactly the opposite from where he says they are going to be...

 

Thanks Hammer. Maggy Y on order.