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Alright. Perhaps some people who know more about this can help me out.

Intakes
It is my understanding that the purpose of aftermarket intakes is to increase either the amount of air brought to the engine, decrease the temperature of the air brought to the engine, or both. Now, CAI's are all twisty and turny, so doesn't this create more resistance? Does it slow down the air or anything? I read somewhere that SRI's are better because they are straight and allow more air to flow directly to the engine. Does the cooler air from the CAI make up for this? Or did the person who said that SRI's are better just now know what he was talking about.

Exhausts
Same thing. Why all the bends? Wouldn't an exhaust be able to pass more air through it, quicker, with less resistance if it just went straight to the back of the car?

Like I said, I have no idea so some car tech guy please explain this to me [IMG]i/expressions/face-icon-small-smile.gif[/IMG]

Thanks,

IronFist

 
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Here are the numbers for the intakes: AEM Site Click on the red dots.

As far as exhaust goes, we need backpressure on N/A engines. Turbo's actually benefit from free flow because it helps to spin the turbine. As the exhaust gases exit they spin a the turbine that attaches thru a rod to the intake side. This compresses the air and sends more into the engine. Hence the less air out the less air in. When it comes to our engines you really need backpressure or you loose torque like a ****.

Hope this helps.

Edit: lemme answer some of your intake questions:

The CAI doesn't restrict the air. The shape has no effect on the resistance, it creates a vortex that spins the air comming in allowing for more air to pass in a measured time. The benefits of cold air are more air in the same amount of space. SRI uses hot air from your engine compartment. That's bad unless you can create a cold air box. If you live somewhere where you drive thru puddles then SRI is better.

SRI for A/T
CAI for M/T

 
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Well intakes are supposed to give power by making it easier to provide air to the engine, and the cold air IMO is not cold, cold air but colder than the one the stock air box gets.

As for exhausts, in mos Cat-Backs the diameter of the pipe diameter is larger than stock, and it bends less, leting the air flow more freely, you still get restrictions from the Cat, but not anymore from the pipes diameter.....

 
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silverdevil, thanks for the response. What is a cold air box?

IronFist

 
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A cold air box, now I am not positive about this but I would say that a cold air box is a box that cuts out some of the hot air caused by the engine. I have a pic here of the K&H SRI, this is what I would call a cold air box.

 
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Also seeing as your looking for info on these parts, here is a link to a whole conversation about 1 member who uses the K&N FIPK (SRI)

Linky link

 
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It is a box that supplies cold air to the intake via a substance, like solid water or ice. And water will not get into the intake b/c the air box is usually around the pipe. For those who like superchargers, try rerouting your air conditioner to or into your intake. It takes performance but it should return more than you give. 50-60 ºF is a lot better than the ambient air and the air in the engine bay. Just a thought.

 
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Essentially, the CAI is called that because it is pulling air from further from the engine, hopefully from outside near the ground or front of the car. The bends in the pipe are not that restrictive as long as they are mandrel bends (where the bend is smooth and no folds or pinching occur).. and if you notice, some CAI's pipes decrease in diameter near the engine, causing the air to be lightly compressed as it flows into your intake.

A SRI, while having less of an air path, and less (bent) pipe for the air to travel, is pulling hotter air from right by the engine, so the gains should tecnically be less as a result of it.

The goal really is to direct the coolest possible air to the engine with some compression to give the engine more to burn with.

The gains you will get obviously will vary depending on the temp outside and your elevation. If it's cold out, your incoming air will be much colder than when it's 100f out during the summer. And if you live up in the mountains, your car will not get as much oxygen to burn, hence a decrease in HP gain at the wheels from the same setup say in the flat lands.

Which is better? That depends on the car, the elevation, the temp outside on avg, and the product you are using.

I lik the idea of redirecting your AC into the intake... I wonder if that would work and how much HP at the wheels you'd gain versus the HP lost to power the compressor. Anyone tried this?