I couldn't find much on this topic, but I have researched intake options for our cars, and I've found the OEM 997.2 intake to be the best one. I've even read somewhere that the 997.2 airbox outflows the 997.1 X51 airbox as well.

It supposedly bolts right into the engine compartment, with the problems being the oil filler tube and the engine compartment fan interfering with the airbox, both of which I believe I have an idea to get around. The throttle bodies on the .1 and .2 cars also seem to be positioned differently.

Looks like I need to cut the decklid for a second cold air snorkel and order both .2 specific snorkels to make it work for now.

I'll do a test fitting this weekend and see what else is needed. This should pair nicely with my GT3 throttle body.









There appears to be a vacuum actuator in the airbox, which I can only assume is controlled via the intake. The line appears to have been cut. Is this a Helmholtz resonator?

 

It's not cut its just slipped off the metal vacuum line.

 

I see. Hopefully I'll be able to remove this thing.

 

Kev! Congrats man. Don't cut your decklid. You can have mine when I fit my $26 spoiler. lol

I have a thread saved somewhere that has step by step along with pics of someone who converted a 997.1 decklid for a dual snorkel OEM airbox. I will have to do the same for that spoiler I bought (if he actually ships it). Let's chat about it Saturday. I'll dig up the thread and have it ready for you.

 

Sure, thanks!

I'm probably going to order a Getty ducktail later this year. I wanted to cut ventilation holes on the underside of the decklid anyway since it seems that raising the spoiler in traffic helps with intake charge temps (much to my chagrin).

 

This isn't the thread I was referring to but it is probably more helpful since your decklid is OEM you will not need to rivet like the thread I was initially talking about:

http://www.renntech.org/forums/topic...-stock-997c4s/

 

Thanks dude.

Damn, an X51 airbox was $800 back in 2007? I see you can't touch one for less than $1500 now. I may have gone that route instead, but I got this airbox for pennies on the dollar.

 

Lot of work for no appreciable performance gains. I'll be curious about the "before" and "after" - looks and performance.

 

Agree, if its for looks, its a whole big project to make it look stock. For more cold air, look at the K&N system

 

The K&N system doesn't particularly seal itself very well from hot engine air. The .2 airbox definitely has a better way of isolating colder, outside air than warmer engine bay air.

jhbrennan, where did you read about no appreciable performance gains from the 997.2 airbox? I haven't even found many threads on the topic on here, or elsewhere. As far as intake upgrades are concerned, this seems to be the cheapest, most effective solution.

I partially dissected the .2 airbox this weekend. I'll post pics and then dissect the factory airbox on my car and spot the differences.

 

I just did the GT3 TB and IDP competition penleum with stock airbox and get a real kick above 5k rpm. I was told by FVD that the OEM airbox is pretty good on the 997.1 S. I did add the BMC air filter to it

 

Here are some observations regarding my partial dissection of the .2 airbox.




Looking through the intake inlets where the filters mount, there seems to be a large velocity stack in the middle which has a wire mesh screen. I'm guessing this is further insurance against large debris being ingested. The air box does have two drain holes in the corners of the chambers where the air filters sit. I'm sure removing this screen would improve airflow, as it presents a restriction, but the utility of doing so seems questionable.




Looking at the airbox outlet, we see the same screen, this time, cast into the airbox itself, in plastic. This also presents a restriction, but I wonder if this is present for a reason. I would imagine the steel mesh is fine enough to filter out any unwanted debris without this. Maybe it serves a purpose for the MAF sensor, which is an inch or two downstream.



Off to the side is what appears to be a flap for the Helmholtz resonator. It is normally held open like this. Applying vacuum to it will draw the flap closed.





The whole upper part of the intake box seems to be plastic-welded together, but there are some joints that seem to be mechanically joined. Hopefully this doesn't require any removal.

Next, I will see if the .1 MAF fits into the .2 airbox.

 

 

I am digging this post up because I was wondering what was needed to get this done. I have a 997.1 and a 997.1 Turbo Decklid, and it looks like all I need are new snorkels and the re position the oil filler, or purchase a 997.2 filler.

Looking to add the 997.2 airbox vs aftermarket?

Thanks for reply.

 

Carmichael,

If you remove the Helmholtz regulator from the back of the 997.2 airbox, I would like to purchase it from you. Please advise.

Phil