2008 Yukon Denali, 135k miles, part 2!!

[tgui]

Question; I'm planning on welding in a cat right after the y-pipe adapter. Is this too far out to help with the smell?

I know I'll still need to tune out the O2 codes.

 

[randeez]

should do something for the smell and noise. mine isnt to bad but i usually run e85 which doesnt smell the same anyway. and have smoothed out the tune at idle

 

[tgui]

I got some proper lap bands and some sealant. I'm going to fix this leak once in for all.

Seriously, kit provided clamps won't work on the ypipe cross over connection. Partially because by design the driver's U pipe off the header bends still a bit as it enters the ypipe cross over.

I still like the speed engineering kit. If you don't have a spare car or need to get it done in one take, or are super slow like me I can see popping for a $$ kit from kooks or American racing.

I'm still happy. $500 into this kit with the bands, sealant, and oem header gaskets. Edit and stage 8 locking bolts.

Tomorrow:

 

[tgui]

New flanges and sealant later. LOTS of sealant in here. It turns rock hard and brittle when hot. Neat stuff.


Seal was good. A few heat cycles later and the headers werent as pretty. Ohh well.


I had to tune out lots of codes.


Still having issues with the drivers O2 hitting the under body. New drivers engine mount, old passengers may be an issues? I'm looking for shorter sensors or hopefully not needing to dent or cut the body.


Got a spare O2 sensor. Time to cut.


Perhaps this will give me the space I need?

 

[tgui]

With no cats, long tube headers and stock muffler this thing is stupid loud.

Cold start.

Bad highway driving.

Time to find a cat that will fit.

 

[tgui]

I got an adapter to put the resonator back in. I need to quiet things down.




I also got an O2 sensor bung and plug if denting body work doesnt work to clear the O2 sensor.

 

[tgui]

I put the resonator back on. It did in fact quiet things down a bit more so when driving. It's still loud FFS, bit not as bad. I really think adding a cat will make things perfect.

Before

After

 

[tgui]

I beat a dent in. It only rubs now on 1st gear launches. I'll dent more later but at least now it doesn't hit all the time.

Driveshaft and sensor out. I used a regular hammer. The air hammer was too slow.

 

[swathdiver]

Sounds good both ways but know what you mean about being too loud for comfort!

 

[tgui]

I have a vibrant 7835 3.5'' inlet short cat arriving. There is only so much room between the muffler and ypipe. I'd prefer to keep the stock muffler.

I hope its not too far out from the stock location and gets hot enough to tone down the smell.

I picked it up for $380 shipped so if it works almost as well as catted ypipe setups I'll be happy.

https://vibrantperformance.com/catalog/product_info.php?cPath=1527_1326&products_id=2670

7.5'' long