Do you pass emissions with this setup and if so, are you in a tail pipe check area or just an OBD port read?
thx!
Ticking options -- Doug Thorley Long Headers + 2007 GX470
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Do you pass emissions with this setup and if so, are you in a tail pipe check area or just an OBD port read?
thx!
There are no emissions in my area. It would undoubtedly fail a tailpipe test but would pass an OBD2 port test as the O2 spacers prevent P0420/0430 codes.
Thanks for the input. Its a nice SOTP improvement with the factory catback and Y pipe. I'm happy with the LT's.
Some photos of the install. I elected to do it myself because I had a friend who let me use his shop/lift/tools to do the job. Took about 17 hours taking my time to clean/soak the fasteners with a trans fluid/acetone sauce, remove everything carefully, take the dipstick on and off 10 times to get the bend/mounting bolt alignment just right, fluid film all the nooks and crannies of the frame, coffee brakes, help out other mechanics, shoot the s*** with people, get mad, walk away, come back, question life, etc.
14mm 3/8 swivel sockets are your friend along with various ratcheting box end wrenches.
Take the right side motor mount/bracket off, it makes things easier. I tried skipping this step only having to do it later on.
Save the little gaskets for the SAI tubes, you can re use them.
SAI tubes and the DT header fitment is so so, have fun trying to bend the tubes to the header air line rails.
Buy a new muffler donut gasket and whatever hardware you can, it saves time and frustration if you pull the threads off of a fastener when removing it, etc.
Soak your fasteners with some penetrating oil of your choice, its really does help.
Don't rush and you'll be fine. I was on the "clock" so to speak, but taking a break and walking away for 15~20 minutes makes all the difference with this job. Its a marathon not a sprint.
Hopefully this helps someone or even the OP.
Photos:
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Where did you get the spacers? Are you running long tubes?
I got them from Amazon but they have since been pulled. You can find them on other websites still (where they'll likely ship directly from China). Two years in now and they are still working great.
I am running long tubes.
No CELs? Everything running normal? It will pass an OBD2 port emission test?
Thanks so much!!
Yes, yes, and most likely yes. No emissions tests here but has never thrown a catalyst efficiency code, so it seems it would pass a scan-only test.
It would fail a visual test as the absence of upstream cats and O2 spacers are clearly visible under the vehicle.
If you are concerned you can get short tubes and retain the upstream cats and functionality of the downstream O2 sensors. Long-tubes are easier to install and make more power though.
Thank you again. Last question - did you have to have a shop install threaded connections for the O2 sensors? I think I am sold on LTs now.
I think I’m gonna run the LTs, DT Y-Pipe, and some sort of free flow exhaust.
The threaded bung for the upstream O2s are on the DT LT headers, while the downstream O2s go in the same threaded bung as the factory O2 (you just install the spacer in the bung, then the O2 sensor in the spacer). So everything is 100% bolt on.
FYI, the DT Y-pipe had some mixed reviews, and the factory Y pipe and cats are actually pretty free-flowing. I'd suggest keeping it. Also if you run totally catless by removing the factory Y pipe, you have some pretty stinky exhaust. The exhaust on mine with keeping the two downstream cats in the Y pipe is a bit stinkier than stock, but not terrible.
Mine had big power gains after the LT headers, and bit power gains again after adding a free-flowing exhaust. Can't imagine driving a stock GX anymore.
FYI, the DT Y-pipe had some mixed reviews, and the factory Y pipe and cats are actually pretty free-flowing. I'd suggest keeping it. Also if you run totally catless by removing the factory Y pipe, you have some pretty stinky exhaust. The exhaust on mine with keeping the two downstream cats in the Y pipe is a bit stinkier than stock, but not terrible.
Mine had big power gains after the LT headers, and bit power gains again after adding a free-flowing exhaust. Can't imagine driving a stock GX anymore.
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Thanks - are you running the LT's too? Any issues? CELs etc? Anything you would do differently 2nd go around?
Yes I am. Have been running them for a bit now. You can find photos and a pseudo writeup a few posts up in this thread. No issues or regrets, the truck is a beast, no lights, just added power/mpg(mine increased about 2mpg so far) same as @Rednexus . As a matter of fact I followed his insight originally to gather parts for the install. Complete plug and play set up, which is what I wanted.
Only thing I would have done differently is install them sooner
Only thing I would have done differently is install them sooner
