Always struck me as odd that an air filter sitting in the engine area is or can be called a CAI. Mounted in the fender and sealed from engine and radiator heat definitely qualifies as a CAI.
Well back in the day I spent all day on a Dyno testing several cold air kits. The ones that make the most power is a short straight shot. Those fender kits reroute air with bends and it's got a long way to go.
Well back in the day I spent all day on a Dyno testing several cold air kits. The ones that make the most power is a short straight shot. Those fender kits reroute air with bends and it's got a long way to go.
I wonder if that would be the case with the hood closed and no external fan. As far as air flow goes, I would think that so long as the required intake flow did not exceed the flow capacity of the plumbing (air intake tube) it wouldn't matter.
I wonder if that would be the case with the hood closed and no external fan. As far as air flow goes, I would think that so long as the required intake flow did not exceed the flow capacity of the plumbing (air intake tube) it wouldn't matter.
That would be my thought also, especially with a N/A engine. Yet I remember back when Chevy guys would say their intake manifolds were superior because the air came straight in from the front of the engine vs coming in from the side like the Mustang intake manifold. And I have even seen some of those sheet metal intake manifold manufacturers claim that the front facing intake manifold made more power than the side facing manifold on a N/A car. So I would guess that it has something to do with WOT since there is 0 vacuum at that point. The shorter and straighter the tube, the more power will be made I guess...
I guess it comes down to what was called the "ram air affect". I can see in a NA car that this affect may result in more air being available than might otherwise be the case. However, I believe this notion has been scientifically dispelled by Applied Engineering.
Has anyone installed the JLT intake for our cars? It's pricey, but it looks like one of the nicer CAI's out there for our vintage. I've also had the same question as above; does it have a provission for the intake air temp sensor and a port for the PCV line?
Regarding the different types of cold air intakes, there are three factors to considder: 1) Pumping work or pressure drops result in lost power. This is all affected by the bends, couplers, filter flow capacity, and tubing diameter. 2) Air temp has a huge influence on the knock threshold and air density. The colder the better - less chance for spark knock and more air mass into the engine = more torque. 3) MAF metering. If everything else in the CAI is well setup (minimal temp gain and minimal pressure drop), but the meter orientation is setup for asymetric flow across the MAF's diameter, all of the benefits go out the window. The ECU needs a good signal from the MAF, and MAF's generally like straight tubes in front of and behind them to read reliably. Our old school mass air meters/ECU's don't handle air pulsations or asymetric flow very well.
It's always amazed me that magazines and manufacturers haven't done some kind of published CAI shoot-out with REAL instrumentation. It would not be hard to mount a pressure tranducer and thermocouple right at the throttle inlet to quanity these systems. Compare the measured temp increas and pressure drop to ambient conditions and there you have it! It would only take a couple WOT 1/4 mile runs to show the whole story, which would also provide track times to further quantify the performance gains (or losses), so the chassis dyno factor would be eliminated. This would easily settle the big debates between open element vs. fender well, metal vs. plastic tubing, short vs. long tubing, stock system vs. aftermarket CAI, 80mm vs. 90+mm MAF sensors, benefits on stock car vs. one with a built up engine... thes list could go on. Based on the simplicity of the instrumentation and the ease of swapping these parts, this type of scientific test should be first and foremost for a good magazine tech article.