Automotive Exhaust systems
Its all about letting the air out. Sometimes it comes out where it's not suppose to. Sometimes it don't let the air out at all. Sometimes you can help it get out by changing the exhaust system. There's not much to say about the exhaust systems,other than its there to just get the gases from the engine to the outside of the vehicle, to make the sound coming out quieter.
So lets look at what makes up the exhaust system. We start with the exhaust manifolds, move to the exhaust pipe, to the catalytic converter, to the muffler, then out the back with a tailpipe.
If your vehicle has a v8 or v6,then the vehicle will have 2 exhaust manifolds into a cross over pipe, or a y pipe into 1 or 2 catalytic converters, then to the muffler and so on.
There's not a lot that can go wrong with the exhaust systems, but there is a few things that can go wrong or bad.
What if you got an exhaust leak, where's it coming from. There's a few ways to find it. You can make yourself a stethoscope by taking a length of 1/4" vaccum hose, about 2' of it. Hold one end in your ear and pass the other end around the area it sounds like where it's leaking. If it's such a small leak you can't find it by sound, a good way to find it is pour transmission fluid into the throttle body while raving the engine and look for smoke leaking out. Sometimes you will hear a leak when you first start your engine then it goes away a few minutes later. This is a sign of a cracked manifold or a bolt broken off holding the manifold to the head. Most of the time a leak like this will have to be repaired by a auto repair shop. Be careful who you get to repair a broken bolt in the head, some shops will tell you they will have to pull the head to do the repair, that gets real expensive. Find someone who knows how to get broken bolts out without pulling the head.In all my years of repairing automobiles, I have never had to pull a head to remove a broken bolt out of a head. To make a stethoscope to find sound, you will have to modify the stethascope in the picture.
Exhaust System Stopped Up
How do you tell if the exhaust is stopped up.The first thing that will happen is you loss power. I've seen some exhaust systems so stopped up the engine want even start. How do you find out where the problem is.Most of the time now days, it's caused by a clogged catalytic converter. How do you know what to look for, well you can pull the front o2 sensor out of the exhaust and see if the engine gets some of the power back. You can drill a hole in front of the convertor and install a pressure tester to see if you have any back pressure on the system. One way to tell if the exhaust is stopped up is to listen for a hissing noise coming out the tailpipe, or the air cleaner makes a loud noise. A big mistake people make is when they loss power they think they have a stopped up exhaust, an they really have a bad fuel pump or clogged fuel filter. So you need to do a back pressure test and a fuel pressure test.
A Big Miss Conception About Catalytic Converters
So your check engine light comes on, and you go by your local parts house to see why your check engine light came on. They tell you that you have a code PO420,which is a catalytic converter trouble code, what it actually says is Catalyst System Efficiency Below Threshold (Bank 1).They tell you that your catalytic converter is clogged up.
Maybe, maybe not. What is the code really telling us. Well what it means is that the catalytic converter is not cleaning up the unburned fuel that did not burn in the cylinders. That means 1 or 2 things,1 the material that is inside of the convertor is coated with is worn down where it is not doing its job, or 2 the material that is in the converter is no longer in there, another words gone. I could go into further details about how the system actually works, but that would just confuse you even more. Now sometimes when you get this code and you don't have any power, it usually means you have more than one catalytic converter. Some car manufactures use 2 catalytic converters, one behind the other, and what happens is the material from the front converter comes apart and gets stuck in the rear converter, clogging the rear convertor. Most of the time when this code pops up, you don't feel the engine runs any different, you would not even know you had a problem if the check engine light didn't even work. But if you want the light to go out and stay out, your going to have to replace the catalytic converter. You don't have to go to the dealer and have a catalytic converter replaced ,unless it's under warranty.It is much cheaper to get the catalytic converter replaced at a muffler shop, you can save 100's of dollars, sometimes 1000's.Sometimes the catalytic converter has an extended warranty, Most car manufactures have a 7 year-70,000 mile warranty on the catalytic converter, some are 8 year-80,000 miles. The picture on the left is of a good, clean catalytic converter, middle picture is of the material inside converter, right picture is of a catalytic converter stopped up.
Duals Or Single Exhaust
Do you put duals on your vehicle or not. So why do you want to put duals on your vehicle, is it for more power, is it for better gas mileage. Now days it really doesn't make any differents on either one of those things. Now days the cars are built with computer systems, with fuel injectors, and programs that control timing, fuel/air mixtures and transmission shift points. Putting duals on a vehicle today is a waste of your money. It's not going to help you, in either of those cases. Now if you want a better sounding exhaust system, you can get that from a single muffler with a dual outlet, and running dual tailpipes out the back, with some echo tips. Now this exhaust system I'm writing about is the way to go for a truck. Now for a Mustang or Camaro or any car with a v8,then duals from the catalytic converter back sounds the best. Doesn't help gas mileage, but does sound awesome. Sometimes you can go with mufflers or without. I know that I removed the mufflers off the rear of a Challenger, and ran straight pipe with the tips reinstalled, and joked with the lady that owned the car that it sounded just like a 5.0 Mustang. It really sounded good. Don't get me wrong about duals, they do help performance some, but you have to do other things along with the duals. Something like headers, a programmer and a cold air kit. Those things together make a big difference , not only on performance but gas mileage too.
You can buy a stethoscope like this and remove the metal tubes and ball off the bottom. Put a vacuum Y in the hoses and add some more rubber hose to the end of the Y. Then add a piece of brake line tube to that, so you can have something ridged to hold on too.
At my shop, I do custom exhaust work. I can run duals from the engine, all the way out the back. Most of the time I install a single muffler with dual outlet. Then I install dual tail pipes out the back, either straight out or angled out the side. Sometimes I dress it up by installing chrome tips. I would be very grateful if you would give me a chance to install some exhaust on your vehicle.