The carbon content is also the reason why these run of the mill cast iron turbo parts rust easily, and over a very long term duration do crack. It is to be noted that cast iron turbo manifolds are stronger than welded manifolds. Even a properly welded turbo manifold, will fail much sooner than a cast iron manifold. Hereof, why are exhaust manifolds made of cast iron?
Exhaust manifolds are generally simple cast iron or stainless steel units which collect engine exhaust gas from multiple cylinders and deliver it to the exhaust pipe. This decreases the amount of heat given off into the engine bay, therefore reducing the intake manifold temperature.
Secondly, can you use headers with a turbo? If you use a header in combination with a turbo say a race style setup you are going to use a heavier grade stainless material and design it to give optimum flow to the turbo itself. They have their benefits but again this wouldn't be something I would consider a bolt on or simple setup. You technically can.
Furthermore, what does a turbo manifold do?
A turbo manifold is a series of runners, or pipes, that collect exiting exhaust gases which can then be channelled into a merge collector.
Why are headers better than manifolds?
Why are headers are a better choice than an exhaust manifold? As stated above, exhaust manifolds create back pressure, which lowers performance. Because each cylinder of the engine is given its own tube, however, headers eliminate this problem; thus, allowing the gases to exit without the creation of back pressure.
Related Question Answers
Do headers increase HP?
In general, a quality set of headers should provide an increase of approximately 10-20 horsepower, and if you're restrained with your right foot, you may even see an increase in fuel mileage. Can you weld cast iron?
Cast iron is difficult, but not impossible, to weld. In most cases, welding on cast iron involves repairs to castings, not joining casting to other members. The repairs may be made in the foundry where the castings are produced, or may be made to repair casting defects that are discovered after the part is machined. How long do exhaust manifolds last?
two to three years
What are the symptoms of a bad exhaust manifold?
Symptoms of a Bad or Failing Exhaust Manifold - Noisy engine exhaust. One of the first symptoms of a problem with the engine exhaust manifold is an excessively loud exhaust.
- Decreased power, acceleration, and fuel efficiency. Engine performance issues are another symptom that can be caused by a problematic exhaust manifold.
- Burning smell from the engine bay.
Does exhaust manifold increase HP?
Automakers need to meet emissions requirements and keep production costs low—and one result is that stock exhaust manifolds, the systems that move poisonous air to your exhaust system, aren't as efficient as they could be. This makes aftermarket exhaust headers a good place to find extra horsepower and increase torque. How much does it cost to replace exhaust manifold?
The number for an exhaust manifold repair cost is an average of between $570- $900, with the labor taking up the majority of this price at between $400 and $550 of that, and the ports running you between $130 and $340 for the total cracked exhaust manifold repair cost. What material is used for exhaust manifolds?
Since about the mid-1990s, plain carbon and low alloy steels have been replaced by stainless steel as the primary material for exhaust systems downstream of the exhaust manifold or turbocharger. Do turbo cars have exhaust manifolds?
Much like the exhaust manifold for naturally-aspirated vehicles, turbo manifolds serve the same function to channel exhaust gas out of the engine. However, instead of sending it out to the remainder of the exhaust, turbo manifolds direct exhaust gas into the turbine housing of the turbocharger. What is a turbo flange?
A turbo flange is a piece of metal that has been machined to connect a turbocharger to an intake or exhaust system. Commonly made of mild steel or stainless steel, a turbo flange can also be manufactured from aluminum. What is a log manifold?
The stock 2.7T manifold is classified as a “log style” because of the way that each exhaust port in the cylinder head discharges its exhaust pulse into a long single tube running the length of the manifold. A log style manifold design works much differently than a “collector style” design. How hot do turbo headers get?
How hot do turbo headers get? Ordinarily, the temperatures of the muffler are usually between 300 to 500 degrees F. However, it is capable of handling more temperatures up to 1200 degrees F. When these temperatures are extreme, the catalytic converter is likely to get damaged. Does a turbo manifold replace headers?
The turbocharger manifold will replace the stock exhaust header and connect to the car's exhaust system. Once the turbo charger is attached to the header connect the turbo header to the engine's exhaust system. How much horsepower do headers add to a 350?
The length of the primary tubing determines the effective rpm range, but headers can be worth 15-20 hp on the right application. Run on our restrictive two-barrel 350, the headers improved the power output to 248 hp and 365 lb-ft of torque, with consistent gains through the rev range. Are headers louder than manifolds?
Another disadvantage of headers is that, due to their thinner walls, they do not absorb as much sound as cast iron exhaust manifolds, making them louder (although some may see this an advantage). Are headers street legal?
Headers aren't always illegal, some vehicles come stock with them and most short tube headers are considered legal in most states. Not only will they make your vehicle louder, but it is also considered tampering with your vehicles emissions, which according to the EPA is illegal under federal law. Are shorty headers worth it?
If you're driving a turboboosted engine, you will absolutely want shorty headers, but they're also great for a variety of other drivers. If you're looking to increase the performance of a vehicle that's primarily your daily driver or commuter, shorty headers are a good idea. Are shorty headers better than stock manifolds?
Although shorty headers don't always produce as much low- and mid-range power as full-length headers, they do provide significant power gains over stock manifolds and have the potential to produce higher rpm power gains. You can maximize the performance of your shorty headers by opting for equal-length primaries. Do shorty headers require a tune?
You should be fine without a tune. Do headers make the car louder?
Besides, will headers make car louder? Headers alone will not make it any louder. Exhaust headers are rarely found stock on vehicles; most vehicles have what is called a standard exhaust manifold. Headers decrease restrictions, therefore increasing horsepower and sound. Why do headers increase horsepower?
By installing exhaust headers, you are aiding your engine in its ability to push gases through the cylinders. Doing so alleviates excess back pressure in the manifold. Thus, when headers remove the exhaust, there is a surplus of clean air, allowing the engines to increase horsepower production. Whats better short or long headers?
For shorty headers, the port pipes actually merge into a single exhaust pipe in a much shorter distance. For long tube headers, the exhaust pipes are much longer and merge farther out. Long tube headers build a ton of power in the mid to high RPM range. They are the best option for high-rev vehicles, and track terrors. 
