Cold Air Intake Usefull ?

theDreamer

Price per power for the Z:
~High flow cats
~Intake
~Exhaust

HFC & Intake are about the same price and have proven gains by forum members here which are similar in results. I think HFC can get you about 2-4 more HP overall, but Stillen Gen III putting down 15-18 with proven results is hard to pass up. The stock box is technically a cold air system but by itself is restrictive more than aftermarket systems. Like 1slow370 said, the accordian lines, the filters, even grabbing the behind the radiator is not helping.
Now you can easily just throw on silicon tubes, new filters and a bit of Modshack changes and probably get the same results as many other CAI systems.

To answer your questions more specifically:
1. It has a longer intake tube ! = more air resistance means less throttle response
~Not true, the better piping will help keep things running at the same level.
2. how many degrees are possible for combustion benefit on high flow ? (dynamometer is not street ..hood open ..active e-power cooling with tuner selling arguments)
~Not exactly sure on this one, but from member testing here people do not do hood open or "selling pitch." Members want real world numbers with tough challenges, heck in Texas we get 100° or higher so a major problem with stock box and other options are heat soak engines which are a major factor in power loss. The Stillen Gen III and Injen are always pulling the coldest air you can get for this car.
3. Higher possibility of water blow at havey rain with slopes (the orig-box uses gravity/capacity to get rid of)
~Nope, the Stillen Gen II are to high for water to get close and the Injen are inside an enclosed area similar to the stock boxes.
4. Only sound reasons... opening the VVEL
~Nope, power gains and sound
5. The plus margins i reviewed are not amazing for the price
~Price per HP is above average for this car. Now compared to other cars which can get cheaper parts for higher HP maybe.

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