Cold Air Intake
#16
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It will probably feel more sluggish @ low speeds and low RPMs as the Fabspeed CAI is actually a warm air intake. Once you have some speed and rev's to clear out the "stagnant" hot air in the engine bay, you'll be able to make use of the "gains". An updated tune & exhaust will help maximize that.
#17
Race Director
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The installation has to be suspect. If there is an intake air leak while it is ahead of the MAF it lets in engine compartment air and this is hot and this can result in diminished performance.
I looked up the kit and it consists of a hose and some carbon fiber thingie and the ad claims a 20% increase in air flow. A 20% increase in air flow should produce more than a few HP gain. I mean that's like bumping the engine displacement from 3.6l to 4.32l. One would expect a pretty big increase in HP from that.
I looked up the kit and it consists of a hose and some carbon fiber thingie and the ad claims a 20% increase in air flow. A 20% increase in air flow should produce more than a few HP gain. I mean that's like bumping the engine displacement from 3.6l to 4.32l. One would expect a pretty big increase in HP from that.
On a normally aspirated car, the inbound air charge is introduced into the cylinder because there is negative pressure in the cylinder; the ambient air pressure pushes air into that void. It seems unlikely to me that simply increasing the diameter of the intake tube - without increasing the diameter of every other choke point in the engine such as throttle body, manifold, plenum, runners, etc. - would significantly increase the amount of air being introduced into each cylinder.
If 20% more air was making it into the engine, seems that (in order to avoid leaning out the motor), the ECU would need to significantly increase the amount of fuel being injected into each cylinder, yet to the best of my knowledge the only decrease in fuel economy is due to owners stomping on the skinny pedal because the intake sounds "throatier."
This stuff makes more sense to me on a forced-induction car where you really CAN affect the amount of air being stuffed into the engine; it hardly seems credulous that adjusting the intake tube size without modifying the cylinder vacuum and/or the barometric pressure would produce a drastic performance increase.
#18
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The best proven combo on a pretty stock engine has been a drop-in filter panel like K&N, BMC, etc. along with the silicone hose and getting rid of the snorkel assembly underneath. This has been dyno verified at one point. With that said, I'm using an Evoms at the moment(for the better sound). LOL. But I do still have my old setup that I just described and haven't really noticed anything on the butt dyno between the two FWIW.
One can also easily do their own test by logging MAF values on a Durametric or a professional scanning device compatible with the Porsche system. If you wanna go further, you can get a manometer to see the pressure differences as well.
One can also easily do their own test by logging MAF values on a Durametric or a professional scanning device compatible with the Porsche system. If you wanna go further, you can get a manometer to see the pressure differences as well.
#19
Race Director
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I think some of the intakes do make a difference in peak power at some point in the powerband, but the 20% airflow increase seems incredibly optimistic.
I've had nearly every CAI there is on either my 986 or 996 because I'm a sucker for cool-looking gadgets - but I'm under no illusion that the increase is substantial enough to warrant the costs. Some of them are beautiful, like that new-ish one with two cone filters and the carbon-fiber Y pipe. If I had a pile of money sitting around to spend on stuff I don't need (you know, like my 996
), I'd get one of those.
I've had nearly every CAI there is on either my 986 or 996 because I'm a sucker for cool-looking gadgets - but I'm under no illusion that the increase is substantial enough to warrant the costs. Some of them are beautiful, like that new-ish one with two cone filters and the carbon-fiber Y pipe. If I had a pile of money sitting around to spend on stuff I don't need (you know, like my 996
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#20
Drifting
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You can read/log MAF info with the cheap bluetooth/wifi obd-II readers as well.
#21
#26
Rennlist Member
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I almost hesitate to mention this, but I installed the Fabspeed intake about 18 months ago and did a before after on MAF data (BlueDriver). I don't have the spreadsheet in front of me, but on that day, in that car the air temperature was the same as before or one degree (F) warmer and the flow metric was much higher. How that affects performance is up to interpretation. YMMV, T&Cs apply, blah blah blah.
#27
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I almost hesitate to mention this, but I installed the Fabspeed intake about 18 months ago and did a before after on MAF data (BlueDriver). I don't have the spreadsheet in front of me, but on that day, in that car the air temperature was the same as before or one degree (F) warmer and the flow metric was much higher. How that affects performance is up to interpretation. YMMV, T&Cs apply, blah blah blah.
#28
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I did speak with John at Fabspeed. He said to put some miles on the car and to drive it at the higher end of the rpm to possibly let the ECU do what it needs to. I will do that and see what happens. Thanks for the insight.
#29
Rennlist Member
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That's correct - personally, I was curious what kind of differences the car would report aside from "feel". Sorry, I wasn't responding to your post directly.
#30
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Gotcha. There's been documented increases on replacing stock paper element with higher flow gauze element, removing intake resonator, and using silicone elbow. I just think after that, increases can be negligible in moving to a cone setup unless doing it mainly for sound characteristics.