Header install/DTC Codes

[Decrow]

Cat-Back

I have Love - Hate relationship with my newly installed exhaust. I Love it, wife hates it. So I saw on Ebay a GMPP Touring Exhaust System no tip for 2007 – 12 Tahoe(which from other Thread's people like) so I put a bid on it. Pipe size is 2 3/4", does anyone know what the pipe size is from the down pipe connection to the OEM muffler on a hybrid is? Being that the heads are from the 5.3L the manifolds, downpipe and exhaust should all be interchangeable (in theory). So any way I have a bid on this and the next day I see for $100 more GMPP 3” Cat-Back from a 2012 Escalade with Corsa tip
Oh well I can always buy a tip.

 

[Decrow]

Well... I purchased the GMPP Touring Exhaust listed on EBay for $250 + $50 for the GMPP Chevy tip. This is/was a brand new unused item for a fraction of the dealer cost.
Install took 1hr, in the driveway. I had to raise the back end to allow the pipe clearance between the ground and the axle. This exhaust is nice. I still have a nice rumble, and no drone. Everyone is happy now. If interested I purchased it from frankkentoutletparts, here is a link to one listed at $260.
http://www.ebay.com/itm/NEW-GM-TOUR...=180902326989&ps=63&clkid=9107464510545315190
Now I know if you cross reference with GMPP it will say not for Hybrid, but it does fit, no mods needed. The pipe size is 2 ¾. They do have 3” +, but those or for the 6.2L. Being that the HyHoe has the exhaust system of the 5.3L ithis was a direct fit.
Next item is to replace the header gaskets. I still have this annoying ticking, not sure if exhaust or engine (valve) noise through header.

 

[Ed Blown Vert]

My biggest concern right now about mods is just that there's no software available to tune these trucks. Drives me nuts! I wish HPT could do it. I know they were working on it, but I don't know if they still are or not.

I have been working with HPT and they have been able to read our VCM on a bench.

The beta software they have sent me is real close to reading my computer.
I hope they break it soon.

 

[Decrow]

Ed,
Any update from HPT, and tuning our Hybrids?

 

[Rockytfox]

Decrow, did you get the scoop with the volant?

 

[Decrow]

No I didn’t. Looking at pics of installs, it seem the scoop mounts behind were the tow hook would be (fresh unrestricted air). It would fit on the hyhoe, but with the lack of openings and the lowered chin, I felt this option can wait. I’m still looking for hybrid tuner so I can make any needed adjustments for the CAI and Headers.

 

[Rockytfox]

Sweet. I got my CAI in yesterday and installed it in less than 45 minutes. Loving it so far...Not sure if I am going to do the scoop or not but I think the next thing for me is the cat back. Thanks for the write-up!

 

[Decrow]

Rocky, how you liking your CAI, notice any negatives?

 

[Rockytfox]

Rocky, how you liking your CAI, notice any negatives?

Besides getting on the gas a little more than I used to?? No negatives. I did notice a decrease in mpg the first couple weeks...probably due to the 10inches of snow and the above. I'm now seeing some increases in mpg and haven't thought once about taking it off.

 

[CrashTestDummy]

<SNIP> I also am getting what I think is valve train noise from the headers. First thought was exhaust leak (still could be) all manifold bolts are tight, and it’s the same tinny metal sound on both sides, more noticeable in 4 cyl mode. I have looked at numerous forums with people experiencing similar issues, and some of the responses are that it’s just typical header noise. So, my question to everyone, does anyone have a NON Hybrid newer Chevy with cylinder deact, and headers? Did you have exhaust leaks, or above normal noise?

That's a common sound with headers. They don't muffle the exhaust sound quite like cast iron exhaust manifolds.

Funny you mention you having to 'persuade' the head pipe to fit the JBA headers. I had the same issue with my JBA shorties we put on our 98 Dakota R/T when it was new. That was the only issue. Nice to hear you got some mileage from the install. I'm thinking of shorties for our PPV.