View Full Version : Air Box Mods


DBF
10-19-2002, 11:44 AM
<center><img src="http://pictureposter.audiworld.com/41523/dans82cgt.t.jpg"></center><p>What is the general feeling about swiss-cheesing air boxes? I punched mine out yesterday and found a slight to moderate increase in throttle response. Theoretically this should happen, with a larger volume of air allowed to enter the intake.

Dan

furiousgeorge
10-19-2002, 01:24 PM
I wont swiss cheese my air box, but I was wondering how hard it would be to basically turn the air box upside down, and put some sort of intake on the hood. Looking at the intake for my buddies thunderbirt turbo coupe gave me the idea. I think the hard part would be moving the fuel injection stuff. Theres a air flow valve/sensor in there somewhere, would it work upside down?

CGTBrad
10-19-2002, 02:21 PM
IIRC it is closed by gravity. You might be able to flip it and work out some elaborate spring mechanism to simulate gravity, probably would not work quite right still. I think there is some other stuff in the CIS system that has to be upside right to work...

Supercoupe
10-19-2002, 05:25 PM
As long as you didn't swiss cheese the side near the engine it will increase your performance. If you opened up the box on the motor side instead of the fenderwell side you will be sucking in hot air, which is okay this time of year but when it gets hot again in the spring the hot air will decrease your power.

Cdn Blue Coupe
10-19-2002, 06:28 PM
I've found that if i take off the exhaust pre-heater and removed the thermostat valve
and the fender intake I get a wonderful sound under full throttle.
I also added a heat shield so I'm sucking cool air from the grill
Like you I find an improvement but its marginal. but for the sound,,,,, what the hey, and I've kept the parts so can put it back when ever I want. BTW Ithink there are minimal gians ( if any) for the swiss cheese aproach. my way I mor than double the intake area witht he two openings and especially the flapper removed.
what are the other experiences out htere?

kikincgt
10-19-2002, 08:00 PM
Was Wondering about how to swiss cheese the airbox or if theres been any forced piping air mods made for the cars want to do intake this week.
Scott

Audi[VW]EuRo_StYLe]
10-19-2002, 10:43 PM
is the fuel management computer able to correct the gas to air mixture ratios on these cars?

more air requires more gas.

DBF
10-20-2002, 03:03 AM
There is no fuel management computer on '82 vintage cars that I am aware of. It is not something to worry too much.

furiousgeorge
10-20-2002, 06:30 AM
I would take the cover off my airbox and figure something out, but its so damn hard to do!

Cdn Blue Coupe
10-20-2002, 10:00 AM
Our cars whether 4 or 5 cylinder have a CIS or CIS-e system which uses a air mass sensor (the flat paddle) so the more air the more fuel and it is able to compensate for all conditions and as such suits (most) mods to the engine very well up to its fuel supply limits. Opening the air box will not come anywhere close to these limits.

RSTPerformance.com
10-20-2002, 07:41 PM
First off the airbox I have been told is designed very well. Since Audi designed the system so it "sucks air in" you don't really need to force the air in, However on our race cars we took out the thermo plate (since we don't run it in cold weather we don't need to get that warm air off the header) We then ran two 3" air ducks to the front of the car for air intake. This was to get cold air into the airbox. and since we took out the thermo plate it had 2 inlets to the airbox instead of one, for more air of course. The Result: Nothing noticable (so the Audi pro's where right telling us to leave it alone I guess!!) We also have a K&amp;N air filter. This may have helped but again not really noticable however it is really easy to clean and lasts forever :)

As far as Fuel Enrichment. Autotech makes a device which takes your fuel enrichment and modifies it under full throttle. It is a "Plug and Play" device so no big mods are needed! It made a HUGE difference on our coupe Racecars. (regular 2.2 engine) We have increased the compresion by .5 and the engine has been redone recently as well. I was told that this mod gave an extra 10-15 HP on the dino. I'll be honest I laughed! I decided that for $150 bucks I would try it to solve my curiosity. So after practice and before qualifying I installed it. At the end of every straight I was 3-400 RPM's Higher. I was hitting red line almost 200 feet earlier. My laptimes increased 7tenths as well! It's the only modification that was done betweeen sessions. I did this to actually see if it was better. I don't think I got 15HP but it did help. I'm not sure how much it would help an unmodified engine but since the rules don't allow us to do much ours is basically stock and probably is going to give close to accurate results for an unmodified engine. It is designed for all CIS-E cars (Originally designed for all thos VW guys but it works for us as well) If you want more details or any info just make another post for it and I'll be glad to tell you about it and what it does. Have a great night I'm Audi here :)

Stephen

JeromeS.
10-20-2002, 08:01 PM

squidix9
10-21-2002, 05:02 AM
<center><img src="http://members.verizon.net/~vze4phja/images/airbox.jpg"></center><p>Moreover than cheesing the box, getting a better flow filter will do more. You need to get the largest surface area possible for maximum flow. Also you want the air as cool as possible for maximum density.

A K&amp;N filter will help at first, but as soon as it gets dirty, it will actually hurt.

I run a very large paper filter, it's 7X12", about twice as big as stock. I make sure I use a good filter too, one with many deep pleats. It gets dirty quickly, so I change frequently. I too have a hose running to the grill, so I try to get as cool air as possible.

See below for K&amp;N info, and a pic of my box.<ul><li><a href="http://www.seansa4page.com/resource/airfilter.html">Air filter info</a></li></ul>