Headers definitely make 20-30 ft/lbs more across the range. Power wise they're great, but the ticking noises in the cabin really ruin the comfort of the vehicle and winter is coming, so windows will be up for 6 months. Plus I'd be comparing a cammed 5.3 with headers to a cammed 6.2 with manifolds and 3.5" exhaust. The cammed 5.3 is still 1 second slower 0-60 than a stock 6.2.
I think I'll assemble it with the headers to start then, just to be able to compare. The 6.2 may create different frequency in the cabin due to having more torque down low. The 5.3 lugs bad unless you're revving it, so that creates a lot of header noise.
I will report back when I get mine all done if I get the ticking. I have extra sound deadening in my Tahoe, so I thinking that will help me. You should start with your headers, at least going back to stock manifolds will be easy if you find it's too loud or ticky.
Please do, I am curious. I know my ball socket connection leaks, so that may be contributing. I am going to put some paste there this time.
Possible to get this exhaust to work around the Yukon XL spare? I'd imagine id need to also pickup the escalade bumper. https://www.jegs.com/i/Magnaflow/642/15179/10002/-1
Have you looked into Stainless Works exhaust ? They have a dual exhaust for our series Tahoe along with some other variations. https://stainlessworks.net/chevy-tahoe-gmc-yukon-2015-2019-sights-and-sounds
Looks cool, but my goal with this truck is to make it more quiet . I want it to sound stockish. I'll buy a car to play with soon that will be more radical once I am done with the truck. I am still waiting on my camshaft, probably another 2 weeks, so I figured I would try one more time to seal my y-pipe. I can see why it leaks and I took a picture. There are deep ridges all over where it is supposed to seal. This would be impossible to seal metal on metal. This is likely the source of the annoying noises in the cabin under load. It already fails the vacuum + soap spray test. I can only imagine when real exhaust is going past it. Probably flying out. You'd think after spending this much money, the exhaust wouldn't leak. Disappointing.
I like the project you have going on here! I can guarantee the long tube tick is not any better on these vehicles than it is any other. Im running Speed Engineering long tubes, catless true dual, xpipe, and dumps. Im almost always windows down though, but it ticks, it smells, it's loud. But I wouldn't change a thing haha. I wish I had a video of it but I think the best "stock" exhaust sound ive heard is when I kept the factory long tubes and Y, and replaced the rear most resonator and muffler with a Flowmaster 40. It had a nice V8 tone and rumble but wasn't much louder than stock. Looking forward to your progress!
Kooks 1 7/8". I sanded the ridges down a bit by hand. I just put it back together and did the vacuum test and and it's leaking at both ball sockets and each slip fit joint. When I do my engine, I am going to use Optimum Red RTV which is good to 750 degrees. Thank you! I can't wait to drop the 6.2 in. Love the comfort of the truck but it needs more power. Yeah I am aware of the ticking. The noise I get in the cabin is a clear leak though. You can hear it in addition to the ticking. It's a distinct air escaping exhaust leak noise. I will hear it clearly, then go over a bump (which shifts the exhaust) and the noise will stop for a split second. I'd be fine with just ticking LOL. I just removed my Corsa Touring and went back to the stock muffler. I really just want to be as quiet as possible. Problem is my stock exhaust is only 2.75" and it's beginning to rust through. I'd like to pickup a stock 3.5" from an escalade or denali but they're tough to find and shipping is a nightmare because they're 1 piece. The Corsa sounds awesome at WOT but I don't need the attention on this vehicle.
