Cold Air Intake vs Short Ram Intake – What’s the difference?

We get this question a lot. People ask us the pros and cons and which is better daily. We decided to create an article about this topic to better explain the differences with intakes, which we recommend, and which would be right for your vehicle or performance needs. We will be adding to this as new technology comes out, so please check back often, or add a comment about how a short ram intake or cold air intake has worked for you.
What is the difference between a cold air intake and a short ram intake?
As the name implies, a short ram intake is "short". Due to it's size, the intake pipe doesn't stretch far away from the intake manifold, so the air filter remains somewhere near the engine. A cold air intake has longer piping, and is designed to push the air filter away from the engine into an area that has colder air, hence the name cold air intake. Typically, since the cold air intake draws in cooler air it usually makes more horsepower than a short ram. However, depending on engine design, this isn't always the case, and we'll explain further below. A short ram intake is generally less expensive as well, and easier to install and service since the air filter is typically easy to see when you pop the hood. A cold air intake is longer, and places the air filter farther away, sometimes in a fender, so installation is more difficult as is service, and is usually more expensive.
Short Ram Intake
The short ram intake is generally designed to replace your stock air box. Most stock cars come with a plastic box with a plastic hose connected to the throttle body (or directly to the turbo). A performance aftermarket short ram intake typically has a hard pipe made of aluminum that replaces the stock rubber pipe, and the stock air box is replaced with a open element air filter. This generally gives you a good power increase over stock because you are replacing the restrictive air box with an open element air filter, and replacing the rubber hose (which is usually accordion like on the inside) with a smooth metal pipe. Most quality short ram intakes are calibrated through design to keep the stock air/fuel mixtures the same as stock to not throw any check engine lights. Sometimes a manufacture won't offer a cold air intake when their research shows it doesn't increase power over a short ram intake.
Cold Air Intake
A cold air intake is designed to place the air filter as far away from the hot engine as possible. Especially important when your radiator fan turns on, it will not blow the hot air into your air filter as with most short rams. Some manufactures make the cold air intake so that it places the air filter inside a fender or under a fender to try and capture as much cold air as possible. When an engine takes in colder air, it's packed with more oxygen, and creates more power. When a intake manufacture tests the intake, they test different air filter locations to see which is the coolest location. This usually creates more power over a short ram, but due to the location the air filter gets dirty faster, is harder to install, and harder to maintain when the air filter needs to be cleaned.
Do I need a bypass valve?
An air bypass valve is designed mainly for the cold air intake. Since the air filter is placed so low in the engine, it can suck up water when driving over a puddle or in heavy rains. If your intake sucks in water, the engine will likely hydro-lock, and be destroyed. A bypass valve attaches to your intake pipe, so that if the air filter does become submerged in water, the air will instead go to the path of least resistance, and get pulled in through the bypass valve, and usually not suck in any water. Highly recommended for rainy areas.
Which intake sounds better?
Usually a short ram intake would be louder, since the pipe is shorter in length and closer to the throttle body. A cold air intake isn't much quieter, but might sound a little less deep due to the air traveling a farther distance in the pipe and the pipe almost acting as a resonator. Both give your car a strong deep tone when on the throttle that is undeniably a modified sound that any enthusiast recognizes.
Are air boxes better than open element air intakes?
This really depends on your vehicle. Some vehicles are designed in a way that places the air filter in front of, or near the radiator. The problem with this is that the air filter will get hot air pushed into it when the radiator fan turns on. One way around this is to put the air filter into a box that blocks the air from the radiator fan from directly hitting the air filter. For vehicles with a design like this, an air box would be better. Keep in mind also that sometimes an open element air filter doesn't necessarily make more power than a properly designed aftermarket air box. The air box can also keep the air filter cleaner, requiring less maintenance.
Is it better to have an intake with a dry air filter or an oiled air filter?
This is up for strong debate. Manufactures that use oiled air filters claim they capture more dirt particles. Enthusiasts say that the oil in the air filter can get sucked through the filter, and clog the mass air flow sensor (MAF or MAS) and cause erratic readings. Now a days, most manufactures offer a dry filter that does not need to have oil applied to it. We have had good luck with dry filters, and don't see any need to go with an oiled filter if possible.
What are some short ram intake brands?

AEM Short Ram Intake
K&N FIPK Kit
Weapon R Secret Weapon Intake

Above you see an Injen Short Ram Intake installed on a 2007 Honda Civic Si. Notice how the intake remains in the engine bay. This is the stock location for the factory air box.

Above you see a cold air intake on the same 2007 Honda Civic Si. Notice how the air filter is not in the engine bay. We circled the intake pipe that runs from the throttle body down under the car into the driver side fender well. The arrow shows the intake pipe.
We hope you find this useful and it helps you decide which intake you want to purchase. You can see our catalog of short ram intakes or cold air intakes and if you have any questions, please leave a comment.

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Engine Building for Power and Reliability

If you're planning to do some serious modifications to a four stroke engine, you'd better do it right if you don't want to end up with an expensive pile of scrap metal. It's easy to slap on a turbo and run mild boost on a stock engine or even fitting a bigger turbo to an OEM turbo engine, but if you're looking for serious power, you have to rebuild the subassembly to ensure that it can handle the additional power without disintegrating. Obviously you need to ensure that your drive train can handle the extra engine power as well, but in this section we'll discuss engine building for maximum power, starting with the subassembly.

THE CYLINDER BLOCK

You've got to start by ensuring that your cylinder block is race grade. Even if you're just building a street race car, engine tuning would be senseless if the block is not up to the job. Start by pressure testing the block. If you have an air compressor you can do this yourself. Strip down the engine but leave the Welch plugs and oil gallery plugs in place. Fit the bare cylinder head to the cylinder block using new head gasket or one that's not too worn. Close all water opening off with steel plates. One of the plates must be fitted with an air line fitting that you can connect your air compressor to. Gradually increase the pressure in the block to 40 psi. Don't increase the pressure too quickly as a loose fitting Welch plug or a weak spot in the block could blow out can cause you serious injury. If everything is still in place, gradually increase the pressure to 50 psi. Now spray the block with a mild water/detergent mixture. Carefully check the block for air bubbles. If you see bubbles, either have it repaired or test another block. If you get no bubbles, release the air pressure and remove the cylinder head. Use a plug tap to clean the head stud and main bearing cap threads and chamfer any stud hole that is not already chamfered. This will prevent the thread from pulling up. Grind away any casting sag, especially around the main bearing webs, the sump pan deck, and the valley area of a Vee engine. This will prevent cracks from developing. Now remove all the Welch plugs and oil gallery plugs and have the block boiled and cleaned in a chemical bath. This will remove all rust and scale in the water channels, and the caked oil in the oil galleries.

THE CRANKSHAFT & CON RODS

Chrome-moly forged con rods

The stock crankshaft and con rods are usually cast iron items that can be retained if the engine is not required to handle high boost pressures, high horse power, and high revs. Forged crankshafts and con rods are much stronger and are more suitable for high load, high rev engines. In either event, you should have the crankshaft and con rods Magnafluxed to check for cracks.
If the crankshaft has no cracks, check it for straightness. A crankshaft that is even 0.002in out of straight will increase bearing load and will be the cause of bearing failure. If your crankshaft is out of straight, you have two options  either have the crankshaft straightened or machine the crankshaft's main journals so that crankshaft rotation is true. However, straightening a crankshaft that is to be used for a high boost, high horse power, and high rev engine is a waste of time and money as the combustion pressure and inertia loads will reverse the straightening process. Machining the crankshaft journals will also weaken the crankshaft. Ultimately, replacing a bent crankshaft is your best option.
It goes without saying that all the crankshaft journals should be checked for roundness and size. The same goes for the big end on the con rods. The crankshaft, con rods, and flywheel should then be balanced statically and dynamically to reduce shock loading and vibration.

THE PISTONS

High strength forged pistons

The next thing you need to consider is the pistons. Most OEM engines are fitted with cast aluminum pistons with a slotted oil groove. High performance OEM engines may be fitted with hypereutectic cast aluminum pistons that have a higher silicon content. The higher silicon content makes the cast material much harder and more wear resistant, which allows these pistons to withstand greater temperature and pressure loads. This makes these pistons ideal for street racers. However, the higher silicon content also makes the pistons more brittle and prone to breaking under detonation. Thus, these pistons are not a good choice for forced induction applications where the possibility of detonation in greatly increased.
Forged pistons, on the other hand, have much denser and even harder than hypereutectic cast aluminum pistons but are not as prone to breaking under detonation. Forged pistons also have drilled oil holes round the oil groove rather than a slot in the oil groove. This makes them the best option for high horse power, forced induction engines.
Pistons can also be either full skirt pistons or slipper type. The full skirt pistons are heavier but stronger and less prone to wobble. Needless to say, they would be the best option for any engine modification project.

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For modified cars and tuning cars

This Web site is not just dedicated to building pimped out cars and custom cars, but to building and tuning fast modified street cars and even faster modified race cars. Custom-car.us will provide you with all the information and articles about modified cars, car customization and car modifications that you will need to build really fast modified cars for street use or for track racing. Our aim is to help you modify your car and its engine to improve engine performance and handling by providing you with all the information, tips and advice you would need to select the correct high performance auto parts for your car, to install them correctly, and to tune them. It doesn't matter whether your car modification project entails building really cool custom cars, fast modified race cars, cool modified street cars, or even pimped out cars we will provide you with the information you would need.
Information about engine tuning and car modification can become quite technical, but we attempt to bring you this information in plain English. We make the information as easy to understand as possible so that even the novice can learn about car tuning and car modifications, as well as how to increase engine power. We also guide you through engine tuning, performance tuning and car modifications for all makes of cars, including BMW, Honda, Ford, Nissan, and much more, with detailed, step by step tuning and modifying tips. And if you do get stuck with a technical term, there's always our glossary of modified car terms that you can checkup the term. If that doesn't help, you can always send us a message through our feedback form.

We discuss various techniques of car customizing and various car modifications, as well as the different car tuning methods you can use to increase engine power, maximize car performance, and build great modified cars; including:

Engine Tuning Learn about the basics behind car modification and engine tuning. Learn how to increase engine power and build engines for power and reliability. Go to Engine Tuning		Cylinder Head Porting Learn all about performance camshafts and cylinder head porting. Also learn about valve timing, camshaft timing and how to degree your camshaft. Go to Cylinder Head Porting
Nitrous Injection Learn how to design wet and dry Nitrous Oxide Systems for your car. Also learn how to install NOS kits to your car and how to test and tune them. Go to Nitrous Injection		Turbochargers Learn how to select and install the right turbocharger kit for your car. Also learn how to minimize turbo-lag and how best to tune a turbo or twin-turbo car. Go to Turbochargers
Superchargers Learn about the different types of superchargers and how to select and install the right type of supercharger that will give you the power you want. Go to Superchargers and Blowers		Electronic Fuel Injection Learn how to maintain, modify and tune electronic fuel injection (EFI), engine control unit (ECU) and engine management systems for the best performance. Go to Engine Management
Ignition Systems Learn about the different ignition systems and how to improve and tune your ignition system for turbocharged, supercharged and modified engines. Go to Ignition Systems		Air Intake Systems Learn how to improve air flow in and out of your engine by eliminating restrictions in the air intake system, and tuning the intake manifold and runners. Go to Air Intake Systems
Exhaust Systems Learn how to design and build performance exhaust systems with the correct primary pipe lengths and diameters for all types of high performance cars. Go to Exhaust Systems		Suspension Tuning Learn more about your car suspension and how to tune your suspension to be able to get the most out of your engine modifications. Go to Suspension Tuning
Pimp Your Ride! Learn about ways in which you can modify and customize your car visually to make it look as hot as it goes in our latest section on pimped out cars. Go to Car Styling		Free Wallpapers Custom-car.us has free modified car and car logo wallpapers for your desktop. We also have great modified race car and modified street car wallpapers. Go to Wallpaper
Join our forum! Join our all new modified and custom car forum where you can discuss your custom car projects, get tips on modifying thecar you have, and much more! Go to our Forum		More Car Pictures Custom-car.us also brings you free car pictures from the top car shows around the world, including the well known Tokyo Auto Salon and the SEMA show. Go to Car Shows

Although it does not have a lot to do with engine power and car performance, we do discuss ways in which you can modify and customize the appearance of your car to make it look as hot as it goes in our section on pimped out cars as it has everything to do with customizing cars, custom cars and modified cars! After all, what is the point of having a hot custom car if it looks a dud, unless you want the sleeper look?
We will be updating this Web site and adding more information on a regular basis so that it can serve as a complete resource on modified cars, custom cars and car modification. We hope that you find this Web site and its car modification guides informative and useful for building your own cool custom car, performance tuning your own car, and getting the best performance out of your car. All the information presented here has been thoroughly researched by our contributors. In our quest to provide the best source of information on car tuning and car modification, human error is always a possibility. Therefore, you should always consult your motor mechanic about your specific car before performing any car modifications to it, and always take the necessary safety precautions before tuning cars and engines! Should you find any errors on our Web site, please inform ourwebmaster so that we can correct them as soon as possible. You should also note that some car customizations, such as increasing your car's ride height, can adversely affect car performance and safety, while other car modifications may be illegal in your area. You should always ensure that your car customizations are legal

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