Drilled Airbox ?

JG911 · 10-22-2007, 02:33 PM

Just wondering if i drilled my airbox on my 3.2 1984 carrera if it would make any difference and help the K&N filter ?

Also what do people think of the anti backfire safety device's you can buy ?

Thanks.

JMatta · 02:42 PM

The factory drilled the airboxes in their cars...makes a bit more noise, though not sure if it increases power at all. I've always made mine look like swiss cheese.

As far as backfires, that is more prevelant on the CIS cars and shouldn't be an issue with your 3.2 DME.

304065 · 10-22-2007, 03:04 PM

When I had a 3,2 I had the "Cup" airbox lid which was a regular lid that had the entire flat part and snorkel cut away, only the edge with the clamps remained.

It made a fun noise and that was all. Porsche doesn't unintentionally leave horsepower on the table.

NY65912 · 10-22-2007, 03:56 PM

+1 on what Herr. Cramer hath spoken.

partrin · partrin's Garage

I read somewhere that the stock lid was designed to meet German noise restrictions? (presumably at the expense of a little power)
I noticed some improvement with the K&N, thought there might be a little more there......

I bought a second lid, drilled three 3" holes with my handy hole saw....nothing. Then on track at VIR, revving 4000 and up, I thought another car was alongside me.......+1 on the great sound it makes inside the car. I never put the stock lid back on!

MIK911 · 10-22-2007, 09:58 PM

Contrary to others, I could NOT detect any "induction" noise with a swiss cheese airbox lid. It did make my Flowmaster muffler sound 'lower' in tone, and increased the off throttle 'popping' and burbling. Didn't like it, so sold it to another Pelican.

the · 10-22-2007, 10:06 PM

Bruce Anderson's dyno tests with stock, K&N, no filter, open airbox, etc. on the stock 3.2 are well known and showed that at least with the 3.2, the stock airbox and filter can already flow more air than the engine can process, so there's no gains to be had there.

JG911 · 03:17 AM

What about the safety blow back device any good ?

JG911 · 10-23-2007, 01:44 AM

This is the safety device

RickM · RickM's Garage

Here's one configuration with pics: 3.2 Intake mods: Pics, Info & Good Read

tonythetarga · 10-23-2007, 05:53 AM

Quote:

Originally Posted by JG911

This is the safety device

That looks like a pop off valve for a CIS system and not something used for a 3.2.

Rot 911 · 10-23-2007, 05:56 AM

What Tony said. This is not a problem on the 3.2 engine. As for the drilled airbox, I have one and all it does is make cool sounds.