987 De-snorkel - MPG worse?

[Wads]

There is a story going around that suggests that the removal of the air baffle and or snorkel from the 987 intake can cause fuel consumption to go from around 20mpg down to 10-12mpg!!!!

Have any of you guys that have removed the baffle plate noticed any problems with fuel use or other problems in general (eg. water getting into the engine?)? :lightbulb:

If you don't know what I'm talking about the thread on how and why you would do this mod is here:

http://www.renntech.org/forums/index.php?s...&hl=mystery

Edited July 27, 2006 by Wads

[torresfe]

Wads:

I Remove the restrictor plate on my 05 987 as soon that I figure how to remove the vents, but left in place the snorkle. The plate was remove maybe 2 or three weeks after purchasing the car.

I actually was looking for more trottle sound. What I notice after removing the plate was a little more trottle sound not really noticiable if you have top and windows up; but quicker respond in the trottle specially if you have the sport button press.

So far the car has 4500 miles on the clock and not a single issue. The car has being driven in the hot sun and rainy days too.

About gas consumption; Last week I was driving from Little Rock, AR to Menphis, TN for a dealer Apointment and it was averaging from 25-27 mpg driving 75-80 mph. Ambient temperature was in the mid 90's.

Hope this help answering your question.

I am waiting for delivery of a K&N filter who is on back order till mid August, I tell you how sound and trottle improve once I receive and install it. :drive:

[berty987]

With a LHD car you will notice more results in intake noise as the throttle intake is on the left side of the car. I'd expect a better throttle response at lower speeds as has been stated , but there is a risk that at higher speeds 70 mph + losing the restriction may cause the air drawn in to be too high for the fuelling map in the ECU. The electronics would then over fuel to within a specified tolerance (usually 10%) and after that alter the timing to prevent the engine overheating with a weak mixture. This could explain poor fuel consumption on cars with this mod. Unless you have an ECU remap and find that you are running a rich mixture , or need more air , I'd not bother with removing the baffle or change the filter. The K&N filter is a single ply oil filmed paper element which may allow more sound from the engine and will give better air flow. Be careful the oil on the filter doesnt carry over to the MAF , contaminating it and causing fuelling errors. For this reason I'd replace the baffle to prevent pressurising the filter and causing carry over.

[ghiaguy0]

I de-snorkeled my 2005 987. I was getting 23.2 miles per gallon before I did the mod. I drove for about 500 miles in mixed driving. Now I get an average of 20.8 after the mod with about 500 miles of mixed driving. I may have lost a little just because I was driving harder to hear the air intake. I can hear a little differance and will probably keep the mod on there. It was not as dramatic a change as it was on my 986.

[berty987]

The 986 has a different air intake system to the 987. It was one of the main improvements on the 987 to increase the air flow into the engine and provide a larger filter media area , thus allowing longer service intervals. Since the 987 3.2 and 3.4 engines both share the same intake and filter system , Id suggest that the air flow as built doesn't restrict power on the 3.2 or 2.7 engined cars. Performance improvements can however be achieved by using the 996 throttle body and remapped software from softronic, this doesn't require a hi flow filter or de snorkel to achieve gains though can be further complemented by fitting a free flow exhaust. It probably works out cheaper and with gains that can be sustained if you simply replace the standard filter more regularly than 20 k miles.

The snorkel also acts as a flow straightener for the air preventing whats known as turbulent flow. Turbulent flow in the air can create problems with the measurement at the MAF , possibly this is contributing to the poor MPG , though more likely its to do with the original engine map being set for a different air flow characteristic.

Edited July 22, 2010 by berty987