Exhaust and NC inspections

Not sure if this is the right place for this or not?

Okay, when i had my DynoMax muffler installed i had a direct turndown pipe after the muffler. I did this because i was getting some exhaust fumes and sulfur smell everytime i had my windows cracked or down including the rear window of my 4Runner. With the stock set up the pipe had a resonator on the end coming directly out of the rear. Anyway the dealership says do not ride with the rear window down. I just can't help myself and when the dogs in the back i crack it and the fumes come in. Anyway, i had the muffler dummped and 2 months latter i go for an inspectin and they failed me for exhaust! He told me that in NC the piping has to exit the rear of the vehicle. I went to the exhaust shop and had them put a side exit on right behind the rear tire. I passed after that. Well now it's starting to feel good out again and i've been cracking the rear window and here comes the fumes again!

I am planning on chopping off the tail pipe up near the frame after the rear axle. Does anyone know if this will pass inspection in NC? I called several shops and they said it was okay.



Thanks

Not my Rig but this is what it would look like cut up near the frame:

My 08 Silverado had it turned down just after the muffler, before the rear axle and I never had problems with inspections. I've found it helps to go to the same place where you get any service done so that they know you. My illegal window tint doesn't seem to have any problems either... That's half the reason I don't do my own oil changes. It costs more for someone to do it, but when it's inspection time, it's worth it.

Thanks for the reply. I've just been debating about it for a while now. Time to get out the saw anyone else before i commence to cutting?

Got it chopped and i got to say i should of did it sooner. It looks stealthy with nothing visible and it's tucked up high. I stomped it on the highway with the rear window down and i still get a little bit of the fumes but not as bad as before. It sounds a little deeper now too. I'll report back in Febuary when my NC Inspection is due.

I trust you kept the "trimmings" in case you need them come February? I've been thinking about doing a turn down before the axle for both extra clearance and also to cut down on fumes when I have my rear window open.

I can assure you that doing the turndown before the axle will be a problem in NC Inspection but it will elimanate the fumes. Unless you know someone at an Inspection station. That was my first set up and i loved it but when inspection came the guy failed me for my exhaust coming under the passenger area and not out the rear of the vehicle. That was when i added the side exit. Now i have it chopped back and i think it will be fine. I did keep the side exit piping with my SS tip on it though. Not sure i would need to put it on. If i do have any problem I could get a long clamp on exhaust tip that could extend far enough to where it would exit the rear. I would simply put it on and take it off. I'll post some pic's of my set up soon.

New plans for exhaust tail pipe in the works. Since my tailpipe was cut back up near the frame it did not accomplish what i wanted. I was still getting the sulfer and exhaust fumes in the cab from the rear window being down. Also, I was scethed out about the stupid NC inspection so i just had it welded back on. I have ordered an exhaust lap band clamp from Jegs, some piping, a connector piece and a turn down. I will be cutting from the muffler back off, welding on the connector and using the lap band clamp to take on/off the tail pipe for inspections. I will have my turn down put back on for everything else.

Pic's coming soon.

I understand your concern with the exhaust smell coming in from the rear window being open but......the reason for the exhaust out the rear or side beyound the rear axel is not for the smell of exhaust entirely. It is due to carbonmonoxide gas which is oderless. Your undercarriage is not sealed and there is the possibility of the carbon monoxide gas coming in through the cracks & crevis of the vehicle. It is deadly & will put you to sleep before you know it. I have lost 2 friends to this gas over the years, both seperate incidents, I don't believe either of them had tried to commit suicide. Please concider the possibility of your actions by cutting your exaust end & leaving it under the vehicle. Not only your life but those who may be in your vehicle when the conditions are right for the gas to cause problems. Sorry to be so negitive here.

dsbike:

Sorry to hear about that. I know and understand the consequenses of carbonmonoxide poisoning. I also know that with the turndown pipe dumpped just before the rear axle pointing toward the rear tires should not be a problem. The exhaust flow is pushed down and away from the vehicle this way. I had this set up before and never had any fumes leaked into the vehicle. I know allot of folks out west running this set up for years with no issues. Also, these vehicles are built allot better then older vehicles and everything is sealed up pretty good underneathe. Thanks for the concerns though.

Maybe I'll get A CO detector installed in the rear cabin just for good measure

All I can say is I am lucky the Coast Guard sent me to Alaska a while back. I became an Alaska resident in late 99 early 00 and have not had an inspection since then.

i have smashed the crap out of my tail pipe...and i plan on cutting the tip back about 10" to a foot...just so i can have it tucked up a little better..

I have had my tail pipe rewelded back on 3 times now. Having it so i can take it on/off is going to be great! Going Saturday to have my connector welded on. Also, I might get my body mount's chopped back while i'm there for furture use.

Pic's coming soon

My exhaust tip is pretty mangled right now and I've been contemplating cutting it back. It's worse with the body lift since I raised the rear bumper up and now the exhaust looks like it's just out flying in the breeze. I might grab the saws-all next time I'm in the garage and solve this problem.

I can assure you that if your vehicle does not have a tail pipe it will fail the NC State Inspection. Unless you know someone that will pass you. This is why I am going to customize my tail pipe so i can take it on/off.

I have purchased the following to accomplish this: 2 1/4" Stainless Steel Strap Band Clamp - Lap Joint from DynoMax. These are designed to work with an OD (outer diameter) pipe going into an ID (inner diameter) pipe. It took me a while to figure that out for some reason. Basically the pipes slide into eachother and the clamp holds them down securely and without leaking. Most aftermarket exhaust cat back systems use similar exhaust clamps for easy install of the system. I also bought a connector piece that is 2 1/4"ID and some piping to add to my tail pipe and a turndown that is 2 1/4"OD. These pipes make a very tight connection. The clamp is designed to not crush the piping as well. I will have the 2 1/4" ID connector welded after the muffler. The 2 1/4" OD piping for my tail pipe and turndown.


After looking into using these clamps for several weeks and emailing several exhaust companies I have found that these are the best type of exhaust clamp to use for my set up. I purchased my materials from Jegs online.

http://www.jegs.com/p/Dynomax/Dynomax-Stainless-Steel-Strap-Band-Clamps/744706/10002/-1

I passed last year with it cut off right after the rear axle. This year I have it got off right past the muffler, so I will be interested to see if they catch it!

Yeah i was not to happy when i failed my inspection the first time. What can you do. I should of just went to a different inspection staion after that.

The way i'm doing it now will make it legit and that makes me feel better

A couple of pictures of my set up. Everything worked out great and we were able to modify my stock tail pipe.

Parts i used:



Modified tail pipe with connector piece:



Now I can take my tail pipe on/off for inspections

And finaly the finished product;







Over all I am very happy with this set up.

I will have to check this out the next time we meet up.

Luckily with a pickup truck, I have mine under the bed. I originally had it fairly close to the cab, but the C02 was always a worry, so I extended it so the whole muffler is under the bed.

No worries with mine. Everything is fine in the cabin. I actually had it worse with the rear pipe coming out the very rear then the way it is now.