Fujita F5 IS HERE!!
When Das does his dyno testing, he has stated that he won't test below 4x00 rpms where the engine can't kick down under any circumstances with the throttle floored. I believe they are looking at some means to keep the tranny from downshifting at lower rpms but that requires some electrical work that may or may not be done. I'm hoping that they hack it (as long as there is no chance of permanent issues arising from it) so we can all see if there is an actual, very prominent dip in the powerband with the stock intake, which I highly doubt.
1. Heat soak from the metal intake tube: as you concede that heat soak will not last for more than a few seconds, those few seconds could and can make a difference in the 13+ second 1/4 run. The insulation is a great idea. I think the best intake would be the stock intake box (or similar) and a straight pipe like JoeZ's that's either made out of a rubber/plastic type material or taking JoeZ's pipe and wrapping it with the insulation.
2. Heat soak from drawing in hot air from the engine bay instead cooler air from outside the car: I think someone from the testing mentioned something about having engine temp issues when they had the hood closed with the fujita. This is what I was referring to in this thread. As I stated before, it's just like being stopped at a light or staging area before the 1/4 mile. You're not moving so the intake is going to suck in the hot air from the engine and put it back in the engine, etc. Sure it'll cool down after you get going but if the needle is moving higher from it's usual position, it's probably going to take more than a few seconds to cool the entire block down.
I doubt heat soak on these intake pipes will last for more than a few seconds if you monitor IAT via OBD-II. I wrapped my AEM CAI with Thermotec insulation for this very reason, and it didn't make any measurable difference.
Then we've got a fundamental law of physics to overcome. Any fluid moving from a high pressure region to a low pressure region is endothermic. So what happens when the air goes through a partly closed throttlebody? It gets colder. That's why those "idiot" factory engineers plumbed hot water to the throttlebody - to prevent it from icing up and sticking open or blocking from ice under certain conditions.
So the only time we can even come close to inferring the actual air temp arriving in the combustion chamber (which ALSO has a strong endothermic action going through the intake valve) is when the throttlebody is at WOT and there is no vacuum registering in the manifold.
Let's add to this the real reason the whole import CAI thing got started. A smart guy noticed the OEM tube was collapsing at WOT on a particular car. The material was too soft when the engine compartment reached operating temperature. When the tube started collapsing, it made a significant restriction. Being the bright guy he was, he made a metal tube and eliminated the problem.
This did not go unnoticed by the OEMs. They're using better materials these days. So, if the intake tube isn't collapsing and making a restriction, what does the CAI net you? Not much. A dent in the wallet. More noise that the OEMs can't afford if they expect to meet EPA noise requirements. It can also introduce problems because it has a resonant frequency. If the guy designing the thing actually addresses this issue, you might pick something up, but it won't be without a corresponding loss somewhere else. Hopefully that loss is outside normal operation.
I'm very skeptical of aftermarket intake claims. Maybe you can tell?
BTW, removing the snorkel is super simple. There is just one clip and one 10 mm bold at the top.
http://d.turboupload.com/d/882493/In...isons.wmv.html
1. Heat soak from the metal intake tube: as you concede that heat soak will not last for more than a few seconds, those few seconds could and can make a difference in the 13+ second 1/4 run. The insulation is a great idea. I think the best intake would be the stock intake box (or similar) and a straight pipe like JoeZ's that's either made out of a rubber/plastic type material or taking JoeZ's pipe and wrapping it with the insulation.
2. Heat soak from drawing in hot air from the engine bay instead cooler air from outside the car: I think someone from the testing mentioned something about having engine temp issues when they had the hood closed with the fujita. This is what I was referring to in this thread. As I stated before, it's just like being stopped at a light or staging area before the 1/4 mile. You're not moving so the intake is going to suck in the hot air from the engine and put it back in the engine, etc. Sure it'll cool down after you get going but if the needle is moving higher from it's usual position, it's probably going to take more than a few seconds to cool the entire block down.
Anyway, here is the picture that I tried posting a few days ago, but couldn't due to issues with CL. This is the Thermotec insulation that I put on the CAI in my S2000 with no measurable results (via OBD-II).
Then we've got a fundamental law of physics to overcome. Any fluid moving from a high pressure region to a low pressure region is endothermic. So what happens when the air goes through a partly closed throttlebody? It gets colder. That's why those "idiot" factory engineers plumbed hot water to the throttlebody - to prevent it from icing up and sticking open or blocking from ice under certain conditions.
So the only time we can even come close to inferring the actual air temp arriving in the combustion chamber (which ALSO has a strong endothermic action going through the intake valve) is when the throttlebody is at WOT and there is no vacuum registering in the manifold.
Another "interesting" thing: MPG guys like to play with IAT to maximize thermal efficiency. They tend to like to heat the intake air to promote better fuel atomization. Just another interesting variable out there to consider.
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