Originally Posted by EsotericImage

LOL..

the 1/4" really wont make much of a difference anyways. if your running a 68/70mm TB the 2.75 will be fine

Originally Posted by RyanR

negative. steel piping will retain much more heat than aluminum piping. plus, the steel piping is much heavier. no need to add more weight to the car. especially the front.

Originally Posted by Libertariat

Point taken, regardless, the difference won't be enough to matter.

Your second point is nearly as laughable as the first. It's a pipe on an economy engine. The material construction isn't as prevalent as many would purport. Which notable, again, not really a big effin' deal.

You could also just order some 3" piping from an online hardware store, k-teller, or a machine shop.

My point was this: "Getting a 3" diameter pipe is cheap"

Originally Posted by RyanR

Not a big deal? Try touching AL pipe 5 min after shutting off your engine. Cool. Try it with your exhaust. Not so cool. Maybe you should take a gander at a heatsink. Last I checked they were AL for a reason. http://www.hondata.com/heatshieldgasket.html try taking a minute to learn something instead of just regurgitating what you read on honda-tech.

Originally Posted by Engineers at AEM

Whether or not an inlet system is made from aluminum, steel, or plastic, the thermal conductivity of the duct material has little effect on engine power. We have found that the tuning of the pipe, in addition to providing the coolest inlet air source, are the keys to making useable power. We perform engine inlet-air-temp studies when developing each application to determine the coolest location for sourcing inlet air. In addition to this, we determine the safest location for the inlet source to protect it from highly dusty conditions and water. To this end, we provide a stainless-steel heat shield to help minimize heat soak into the inlet area, as well as to provide protection from dust, dirt and mud.

At light throttle opening, air speed and airflow at the inlet system are relatively low. The high residence time of air in the inlet while at low-throttle settings will increase inlet charge temps when materials with high thermal conductivity are used. Typically, when someone is at light throttle they are not asking the engine to make power. Most likely, fuel economy is the issue.

When the throttle is fully opened however, air speed and airflow increase considerably. Typically, the inlet air speed of a 5.7L engine with a four-inch duct at full throttle is 34 feet-per-second, based on a volumetric efficiency of 70% and an engine speed of 3,000 rpm. Most inlet systems for every intake manufacturer for this engine are 30 inches or less. This means that the air in the duct of a 30-inch inlet length on this engine at the given rpm is 1/10th of a second—hardly enough time to transfer an appreciable amount of heat into the air stream on any system.

Basically, the rate at which air travels through the inlet path under open throttle, when one is asking the engine for maximum power, negates the effect of material heat soak, regardless of the material. We hope that this helps to clear up the issues of material heat absorption in intake systems.