Road Rage

1) I think the TL-S CAI's may help a bit with top-end power by allowing the engine to take a bigger gulp, but the fancy ones that replace stock fenderwell systems have always been suspect in my mind, and here is an interesting article on point:

http://66.96.130.106/archives/2002/0...ir/index.shtml

One thing about this article troubles me: they measure a diff air temp over the thermocouple at speed than the ambient temp. I thought air temp had nothing to do with the air movement over the surface. Or is my thermodynamics memory failing me?????


2) There is also a lot of web forum "expertise" on the subject of CAI pipe material - stainless, aluminum, plastic. The general "expert" opinion is that because aluminum has a higher thermal conductivity (true), it will signifcantly heat the intake charge. This is not true. If you do the engineering math, using even conservative estimates to favor the aluminum is bad theory, you will find that because of the high rates of flow, the pickup of heat by intake air charge is miniscule, and cannot materially affect power. A few degrees perhaps is the diff, so this is anon-issue.

Love those web geniuses!

MikeyB

i have agreed with this for some time....

Beiruty

Just look at couple CAI dynos... 5-10 wheel HPs are no BS!

TWong

Something is really screwed up, they just changed the first few laws of Thermo. Without a cooling source, how on earth can they get below ambient? A TC measures only temp.; fluid medium, fluid flowerate, etc. doesn't make a difference to the final temp. Surface contact and stuff like that affect only response time. This is pure BS. On the other hand a Hot-Wire-Anomometer can measure flowrate because it introduces a heat source.

Now stick your head, arm or other bodily part out the window and it feels cooler when you're moving. That's essentially forced convection cooling. In other words, if the ambient is cooler than you (like 95% of the time) the increased heat transfer of high flow will bring your hot appendage closer to ambient faster. Why do I mention this???? If the Engine compartment of a car is 110°F, then the fast air through the pipes definitely will pick up more heat if the conductivity is good. Only reason to use Aluminum is cost and manufactureability.