What would be the best material to use for a straight pipe exhaust no cat converter and how do i install?
It either has to be BOLT ON or welded in. Non-aftermarket exhaust setups (i.e. meineke aluminized exhaust) will need to have the flanges welded on. Aluminized steel is garbage in my opinion... There should already be piping where the cat was. You're running it just open air cut out (you had the cat cut out?)? No...they'll need to weld the pipe in or weld flanges on the cut pipe in order to bolt it in. This isn't rocket science...it should be fairly straightforward. If you wanted to be cheap why did you remove the cat? You'll never pass emissions/smog or inspection without it. The straight pipe setups you see in trucks (stainless) are NOT cheap. More expensive than most bolt on cat backs because they're custom.
A straight pipe exhaust is just a pipe that starts from the header.Usually built for racing engines, these exhaust systems do not hold any boundaries on gas flow. It is just a straight pipe that starting from the header and goes straight to the air without a muffler or catalytic converter.Employing a straight pipe exhaust can provide your vehicle some extra power and will make it noisier. You need to think about emissions laws and noise laws if you want to install this pipe on your car. That’s why they are not used in newer cars as it can exceed its emissions.Advantages:main reason most car enthusiasts use this exhaust system is its high-performance. These systems help to reduce back pressure, thereby providing more power gains and better fuel economy to most of the cars. However, be careful when selecting the size of the pipe as it greatly affects the torque and horsepower. In addition, these pipe exhaust systems can be dressed and extended up with the help of chrome fittings to provide a great look as well.Disadvantage :These systems have many benefits yet they lack in flexibility. The main drawback of these exhaust systems is the cost, as you need to tune your vehicle according to them. In case you didn’t get the appropriate pipe size, it may make your car lose piles of low-end torque. In addition, by employing these straight pipes in your car will produce loud sound levels that might put you in trouble. So, car fanatics mainly use these straight pipe systems.
Is a straight pipe exhaust better?
It seems like you alerted the green police uh oh! Lets get one thing out of the way: This gentleman asking the question doesnt care if you think he's wrong for polluting a little bit more by removing his catalytic converter. It was a question of whether it adds performance or not. The answer depends on your car, how big the engine is, how modified it is, if its turbo-charged or not, etc. Eliminating your cats and muffler on a large V8 like a truck, or a Mustang or Camaro will greatly reduce the backpressure. There IS a trade off with low end torque. If you dont already have a lot of performance parts on your engine, your not going to get much benefit over running a muffler as long as its a high flow muffler. On the other hand the cats are VERY restrictive and it will free up a lot of power. And it will sound like a traditional musclecar from pre-75, the year they started installing cats. If you have a small car like a civic with a 4 cylinder, then you wont see much benefit either way, unless its turbo'd. I wouldnt run without a muffler. It sounds like crap. But the cats are just in the way. My set-up is a Pypes "off-road" mid pipe replacing the cats and some Flowmaster 40 series mufflers on a '98 Mustang GT. Sounds amazing and big power gain over the original catted mid-pipe. Probably around 20 hp increase. Edit: The "auto technician" who mentions backpressure. That is an old myth that just wont go away. It is the Velocity(speed) of exhaust flow that helps low end power on a smaller engine because it helps to more efficiently suck the exhaust out an the fresh are in the combustion chamber during the short amount of time both sets of valves are open. This is called Scavenging. The exhaust is not the only component that works in the tuning of this scavenging effect. The intake runners, the camshaft, etc, all work together as a system to make an engine run efficiently at a certain speed range. Lack of "backpressure" will not hurt an engine in any way. Unless, however, you take off the exhaust manifolds exposing the cylinders directly to fresh air. That will destroy the valves in no time due to the extreme heat cycles. There you go folks. You just learned something.
Opinions on straight pipe exaust.?
There is not a simple answer to your question. The exhaust system is a major part of how your engine works. A stock engine that cannot adjust fuel delivery needs back pressure to work correctly. Back pressure is defined as the resistance to positive flow. To determine your exhaust system components, you need to find the correct size exhaust pipe that flows at the right velocity. You want the exhaust gasses to exit the chamber and speed along at its highest velocity possible, in other words, a fast exhaust system. A 2" pipe has more velocity than a 3" pipe but less volume. Choose a pipe as narrow as possible for the highest velocity but maintain as close to zero back pressure at the rpm range used for the power range of your engine. A stock engine has a 2-3000 rpm at its best power, so a 2" pipe the maximum size. A modified race engine at 8-9000 rpm would benefit from a 3" pipe and straight exhaust. I recommend you stick with your stock cat's and just get some free flowing mufflers.
Sometimes they improve performance. Sometimes they make it worse.They were common back in the day when you had 8l V8s with no catalytic converters. Straight pipes that exited just after the driver were great. Low back-pressure.But since then, we learned that engines aren’t fans. The exhaust doesn’t come out at a steady stream. It only leaves the chamber when the exhaust ports are open. So sizing the exhaust to take advantage of these pulses can improve performance over “straight pipes”.If you are looking for best economy and tuning, straight pipes won’t be optimal. If you are running a 16l V8 on nitromethane, the backpressure is inconsequential. The exhaust temperature and volume is more important, so you’d want short, wide, straight pipes. They aren’t exhausting gasses, they are exhausting flames.But a 1.3l engine in a street car with a cat on it will do better with straight pipes in all cases, as turns reduce performance in all cases, but “straight pipes” as people think of them, may actually hurt performance.
Dual straight pipes true dual no cats?
If you REALLY want to do this you should use about 2 1/2- 3" piping and a cherry bomb muffler o give it some gut. IF you do this, you truck will no longer be inspectable, if you live in a state that requires it, otherwise you will just get stopped and ticketed by the police for having a vehicle that is WAY to loud to be legal, and it won't be cheap. I would suggest AGAINST doing this. You will also lose power and gas mileage by doing this, as you truck is tuned for back pressure in the exhaust system. IF you want to do something like this, go out and by a Cherry bomb muffler and some piping and fit it to your truck AFTER the catalytic converter and put some headers on it or buy a direct bolt on system made for your truck, you will see better power and gas mileage and get a SWEET sound out of it, and still be LEGAL!!!!!
Straight pipes vs stock exhaust?? Gas Milage.?
It will increase both fuel economy and power. It will also make the truck much louder (I'm talking almost too loud if that is possible). However, there are a few problems with your idea. First of all, most municipalities have sound ordinances and you would defiantly violate them. Also, a 1990 is new enough that it is required to have a catalytic converter. If you get caught, you could be fined. Your best bet is to put a cat back system and new muffler on your Blazer. This will give you the desired effect of more noise, more power and more economy. It will also be less likely to get you in trouble with the authorities. You could also consider putting a cold air intake and performance filters on your truck too. These would also increase power and economy.
I want to cut off my catalytic converter and run just straight pipe exhaust.?
First problem is that it would not be legal to drive on the road anywhere in the USA. After that being a 96 it likely has O2 sensors before and after the cat(s). The after ones will no longer be reading properly and have to be dealt with. You cant just unplug them. The computer in a 96 should be able to adjust for reasonable changes in the exhaust system so I would not expect significant issues there except for the o2 sensor thing. If you want it really loud you will likely also attract attention from law enforcement which is never a good thing even if every mod is legal. You make them mad they will find a way to get you. From my point of view its a lot of risk especially if this is your daily driver. If you live in a typical neighborhood and come home late or go to work early you better hope you dont live near me. I personally hate loud exhaust but hey if its your thing and you do it during the day I can live with it. Its just rude and likely not legal to do it at night where there are people sleeping. Look for offroad groups, they may have more info on such mods since they are more legal off road or look for a small town independent exhaust shop that is not worried about getting caught doing something illegal, they should know what things would sound and perform like. The big cities and chain stores wont go near a project like that because of the possible legal issues, you dont want to mess with the Feds.
The exhaust system effects the cars performance accordingly.(1) Too narrow exhaust flow way.(2) Silencer buffel not allowing exhaust gass/ or chocked.(3) Exhanst valve travel time late.(4) If exhaust break system installed, the system malefunction.Due to the reasion mentioned above the cylinder-head temperature rises above average resulting coolent temperature, valve temperature, comperssion temperature too high, can cause pistion scuffing and so on.