Exhaust Question

[mikeyss]

Does anyone with an Escalade, Yukon, or Tahoe have dual 3" exhaust tailpipes running over the rear axle to the rear bumper? I know it's tight going over the axle and the trucks do have kits for 3" tailpipes, but I haven't seen any for SUV's. I ask because I plan to get rid of my 3.5" stock single system for 3" true dual system. I know the 3.5" stock single is ok for my L9H, but I have never liked a single exhaust system..no matter how good it flows. I HATE one puff of steam out the back. So far I've picked the 1 7/8 ARH longtubes, maybe 2 Corsa mufflers, and Beyea mufflers by the rear bumper for resonators. But if I can't squeeze 3" pipes over the axle, would 2.5" after muffler still work out?

 

[mikeyss]

This is the Beyea muffler I would use as resonators as well as keeping the exhaust completely hidden.

 

[Joseph Garcia]

My 07 Yukon XL Denali has a dual exhaust with 3" tail pipes and 5" tips on either side. The exhaust that I installed is a Gibson Extreme cat back dual exhaust system, with the single 3.5" pipe entering the muffler, and two 3" pipes exiting the muffler. In order to accomplish this, I had to remove the spare tire and its heat shield (as stated up front by Gibson), but this was OK with me, in order to accomplish the objective of having a dual exhaust, with one tail pipe on either side.

I will state, however, that this exhaust is loud, and has some drone on long, low inclines on roads, so it is not for everyone.

Good luck with your search!

 

[swathdiver]

Does anyone with an Escalade, Yukon, or Tahoe have dual 3" exhaust tailpipes running over the rear axle to the rear bumper? I know it's tight going over the axle and the trucks do have kits for 3" tailpipes, but I haven't seen any for SUV's. I ask because I plan to get rid of my 3.5" stock single system for 3" true dual system. I know the 3.5" stock single is ok for my L9H, but I have never liked a single exhaust system..no matter how good it flows. I HATE one puff of steam out the back. So far I've picked the 1 7/8 ARH longtubes, maybe 2 Corsa mufflers, and Beyea mufflers by the rear bumper for resonators. But if I can't squeeze 3" pipes over the axle, would 2.5" after muffler still work out?

So you want the Escalade Sport system? There are posts on here for PNs and bumpers and such.

Flowmaster makes/made a dual system too that exits behind each rear wheel. I would think two 2.5" pipes after the muffler would be plenty for 400-500 horses. Back in the day, guys went slower with the Buicks when they switched to 2.5-3" pipes over the stock 2.25" system up to about 450 RWHP.

 

[mikeyss]

This is what I am after, the exhaust...not the Raptor....well, ok maybe the Raptor too, haha. All joking aside though, I want my exhaust to exit like the Raptor in this picture, but wanted to make sure i could run 3" all the way back there. I may buy the Gibson extreme cat back, use the tailpipes, and sell the rest. I am dead set on having a true dual system because there will be forced induction on this engine in the far future.

 

[gooffeyguy]

So you want the Escalade Sport system? There are posts on here for PNs and bumpers and such.

Flowmaster makes/made a dual system too that exits behind each rear wheel. I would think two 2.5" pipes after the muffler would be plenty for 400-500 horses. Back in the day, guys went slower with the Buicks when they switched to 2.5-3" pipes over the stock 2.25" system up to about 450 RWHP.

I run 2.5" duals on my 500rwhp mustang.

With too big of an exhaust system the scavaging effect will be less, and while you might free up a few hp at higher rpm, you will lose low and midrange torque.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[iamdub]

This is what I am after, the exhaust...not the Raptor....well, ok maybe the Raptor too, haha. All joking aside though, I want my exhaust to exit like the Raptor in this picture, but wanted to make sure i could run 3" all the way back there. I may buy the Gibson extreme cat back, use the tailpipes, and sell the rest. I am dead set on having a true dual system because there will be forced induction on this engine in the far future.

View attachment 239967

Is the factory setup 3.5" the whole way or just to the muffler, then 3" from there on back?


Volumes based on 12" sections:
3.5" has 115.45 cu. in.
3" has 84.82 cu. in.
2.75" has 71.275 cu. in.
2.5 has 58.90 cu. in.


To meet or exceed stock volumes:
If the stock setup has 3.5" out the back, you could run dual 2.75" and have more volume (142.55 cu. in. combined) than the single 3.5". Even a dual 2.5" would have marginally more volume at 117.8 cu. in. combined.

If the stock setup has 3" out the back, you could go down as small as a dual 2.25". I'd hope that you'd have enough space to squeeze two 2.25" or 2.5" back there since you're not lowered.

 

[kbuskill]

1 7/8" primary tube headers and true dual 3" pipes... prepare to be disappointed off the line... my 2 bits.



Bigger primary tubes allow the hot exhaust gases to expand and cool quickly which slows down the flow thereby greatly reducing the scavenging effect of the headers. Bigger exhaust pipes only further exacerbate the situation.

The forced induction is understandable justification to upgrade the exhaust but in the mean time it will definitely be detrimental to low end torque.

 

[mikeyss]

1 7/8" primary tube headers and true dual 3" pipes... prepare to be disappointed off the line... my 2 bits.

View attachment 239996

Bigger primary tubes allow the hot exhaust gases to expand and cool quickly which slows down the flow thereby greatly reducing the scavenging effect of the headers. Bigger exhaust pipes only further exacerbate the situation.

The forced induction is understandable justification to upgrade the exhaust but in the mean time it will definitely be detrimental to low end torque.

I have a 6.2, so I don't think I'll feel any low torque loss. Plus I'm planning on adding a better cam and converter. If by chance I lose a little torque down low, that's ok with me because it'll mean less neck snapping at red lights, haha

 

[kbuskill]

I have a 6.2, so I don't think I'll feel any low torque loss. Plus I'm planning on adding a better cam and converter. If by chance I lose a little torque down low, that's ok with me because it'll mean less neck snapping at red lights, haha

Yes, I am aware that you have the 6.2L. I wish I did but I digress.

Keep us posted on what you end up with and your impressions after the install.

I hope you do the exhaust separately from the cam and converter. Its always hard to tell what effect certain parts/mods have when they are all thrown on at once... too many variables that way.