$20 Exhaust Fix 2019 5.3 z71

Bloody Marty · March 12, 2020

Joined this site a few days ago & have been reading thru a lot of good info here. I closed off the 6 resi's then turned & clamped open the flapper on my '19 TB Custom Dbl cab with 5.3L last night. As mentioned earlier it does make it a little bit loader, mostly at start up but with the Dura-tracs I struggle to hear much difference driving down the road. Thinking of maybe getting a Borla muffler only, (not entire exhaust) this summer?

BTW I turned the flapper clockwise until it stopped, then clamped it, now I'm wondering if it's ALL the way open? Obviously can't see where it's oriented, can someone confirm?? Thanks!!

Edited March 14, 2020 by Bloody Marty

Bloody Marty · March 14, 2020

Anyone?

RadoPhan · March 15, 2020

Trying to see if I can get someone’s help. I recently got a Borla muffler from a highly recommended shop. They were helpful and knowledgeable but before I could stop them in time they had cut off my flapper/valve before the muffler and I forgot to tell them I wanted it on. So they welded it back on and from the pics on here, it looks backwards or just rotated 180. Can someone take some pics on both sides of the valve so I can compare? I’m sure it’s flowing the right direction or else I wouldn’t get a louder tone when I throttle it. Or does anyone know what would happen if it was backwards?

Texasdeere · March 15, 2020

Pretty sure it is clockwise rotation to full open. The part sticking out should be towards the outside of the truck or passenger side. Meaning you should see it when you look under the pass side of the truck.

Texasdeere · March 15, 2020

Ratchetarms · March 15, 2020

That is correct. I think he's worries they may have flip flopped it, intake and outlet, which would be bad, as I would think the exhaust would try to close the valve instead on open it. I will try to take a picture of mine this afternoon.

RadoPhan · March 15, 2020

8 minutes ago, Texasdeere said:

Pretty sure it is clockwise rotation to full open. The part sticking out should be towards the outside of the truck or passenger side. Meaning you should see it when you look under the pass side of the truck.

4 minutes ago, Ratchetarms said:

That is correct. I think he's worries they may have flip flopped it, intake and outlet, which would be bad, as I would think the exhaust would try to close the valve instead on open it. I will try to take a picture of mine this afternoon.

Thanks for the help everyone and yes that’s the part I’m worried about since it’s the actual valve in the inside (driver side) and not on the passenger side. I’m hoping the inlet part is still at the front which would mean they just rotated it 180 degrees and welded it but if not then it’s flipped backwards. Can you also check to ensure that it is clockwise to open it? That part would tell me if it’s in the right direction.

Texasdeere · March 15, 2020

If the valve is orientated incorrectly just pin it open until you can get it fixed. If it is turned around to the other side, the valve should be towards the bottom of the pipe to flap open with the exhaust flow. Either way I would insist on it being installed the original way or put a small resonator in it's place if the valve becomes to butchered to use anymore.

RadoPhan · March 15, 2020

23 minutes ago, Texasdeere said:

If the valve is orientated incorrectly just pin it open until you can get it fixed. If it is turned around to the other side, the valve should be towards the bottom of the pipe to flap open with the exhaust flow. Either way I would insist on it being installed the original way or put a small resonator in it's place if the valve becomes to butchered to use anymore.

Sorry new to this valve thing. What does the top of the valve look like?

Texasdeere · March 15, 2020

The valve pivot point is located towards the top of the pipe. It is not like a throttle blade on an intake or carburetor where it pivots in the center of the bore. When the exhaust pressure is high enough it pushes the flap open and into the top of the pipe. The down side of this design is when fully open it blocks nearly 1/3 of the pipe opening. At wide open throttle this could be considered a restriction in exhaust flow.

Texasdeere · March 15, 2020

Texasdeere · March 15, 2020

The real shame is Borla came up with these improved flappers a few years ago and there is nothing available to buy?

It would be great if they sold these individually!

https://www.borla.com/blog/2018/03/28/borla-obtains-patent-for-pioneering-pocket-valve-technology/

Edited March 15, 2020 by Texasdeere

RadoPhan · March 15, 2020

1 hour ago, Texasdeere said:

So since it looks like the valve should sit more on top of the exhaust pipe and the spring on the driver side, looks like mine is correct just rotated since it’s now on the bottom.

Texasdeere · March 15, 2020

At least the guy took the time to do some nice welds. I think the valves are orientated on the top of the pipe to minimize the affect of moisture over time. Just a guess

RadoPhan · March 15, 2020

25 minutes ago, Texasdeere said:

At least the guy took the time to do some nice welds. I think the valves are orientated on the top of the pipe to minimize the affect of moisture over time. Just a guess

Yeah it was a reputable shop and highly recommended by several people that’s why I trusted them. Figured they would reinstall it correctly. Thanks for your help on this one. I’m assuming it looks right to you