K&n air intake system for porsche 930

[mark houghton]

Where did you get the oil catch can?

Many, many...many moons ago I did an unconventional K&N adaptation whereby I hacked off the end of the stock airbox, brazed on a plate/fitting to hold a huge filter, which opened up the area beneath for access to the WUR and AAR while still retaining all the stock hose connections to the "breadbox". Kinda stupid approach but the thought was to keep the normal tunneled air flow into the air flow metering arm.
Thinking very seriously this time around of trashing the breadbox and going with this more conventional approach.

[stre]

Swapping to a K&N intake on a 930 mainly improves airflow and engine sound, less restriction than the stock box and a nice turbo whoosh. The most common setup is the K&N RU-2970 filter with a custom or aftermarket bracket.

[mark houghton]

Originally Posted by stre

Swapping to a K&N intake on a 930 mainly improves airflow and engine sound, less restriction than the stock box and a nice turbo whoosh. The most common setup is the K&N RU-2970 filter with a custom or aftermarket bracket.

Uhhh...2970 is a dual inlet filter according to K&N. Perhaps they've changed their numbering system. Other options are 5163 and 5109. I do like the oblong shape provided it isn't too tall.

[gorskined]

Originally Posted by levdeb

Afternoon! So just got the K&N filter delivered, as well as a catch can. Wanted to be sure I was plugging the correct hoses, or using the catch can where needed. I love the idea of having it all vent out the wheel well, but not sure which hose should go where...







Appreciate any insight! Can't wait to crank it up..!

the vent hose from the top of the turbo runs into my catch can. The catch can outlet has a filter vent looks like a small k&n and the oil reservoir breather has a small filter vent like the k&n all my breather vent are located in my engine compartment . i have yet to collect any oil in the can or have any oil vent issues in my engine bay from the breathers.

Regards Ned

[Bucketlist]

Went to the K&N several years ago to rid myself off the airbox pain and make adjustments easier. Had a catch can for a while but it was always empty so I sold it and changed to the small air filter at the oil tank vent.

[Alan L]

I have never had anything in my catch tank, and that is all track driving. If I do find oil in there, it will be a bad day.

[ncoder]

Can you guys share part numbers that worked for you?

Stre mentioned ru-2970, but that seems wrong:
https://www.knfilters.com/ru-2970-universal-clamp-on-air-filter?srsltid=AfmBOooR4UgE016NJn3Ptc5VQNAGKF7_CBT zmFa-Lf7HOGamrI9iMZYR



There is this "custom aftermarket bracket" mentioned. Fabspeed sells this: https://www.fabspeed.com/fabspeed-porsche-911-turbo-930-air-intake-system-1976-1989/
but that kit seems a bit overpriced. (unless someone can convince me it's worth the price)

[mark houghton]

Originally Posted by ncoder

Can you guys share part numbers that worked for you?

Stre mentioned ru-2970, but that seems wrong:
https://www.knfilters.com/ru-2970-universal-clamp-on-air-filter?srsltid=AfmBOooR4UgE016NJn3Ptc5VQNAGKF7_CBT zmFa-Lf7HOGamrI9iMZYR



There is this "custom aftermarket bracket" mentioned. Fabspeed sells this: https://www.fabspeed.com/fabspeed-porsche-911-turbo-930-air-intake-system-1976-1989/
but that kit seems a bit overpriced. (unless someone can convince me it's worth the price)

I just bought a RU-5163, will arrive tomorrow. The correct flange diameter and height for clearance. Tired of the breadbox taking up all that room. No bracket needed, comes with a 5 inch hose clamp. $53. You can buy those small filters elsewhere for maybe $20 a pop.

[levdeb]

This is what I used on my 1988 930.

https://a.co/d/hys2S1d

https://a.co/d/bmZRWL1

https://a.co/d/5xqtX6B

Not sure of any power increase, but you can't mistake the sound of that turbo winding up and dumping now...

And its just so much cleaner under the lid. Very happy with the finished product for under $100.

[RarlyL8]

The K&N RU-5163 cone filter frees up a lot of space but like everything K&N it adds no power. We've done dyno runs on engines producing less than 400whp using the OE mailbox, K&N and no filter at all and see zero significant difference in output. I'll post a picture of our carbon fiber filter housing once ready for production. It will retain all of the connections so no auxiliary filter will be needed.

[ncoder]

Originally Posted by levdeb

This is what I used on my 1988 930.

And its just so much cleaner under the lid. Very happy with the finished product for under $100.

Wow. Thanks! That looks soo much cleaner! And super cheap to try. I'll give it a shot.

[mark houghton]

Done...plus a couple cheap Chinese air filters (not shown) for the two breather hoses that used to connect to the OEM breadbox. Probably not really necessary but would catch any oil mist. Haven't run the car yet, just need to slap the IC back on.

[mark houghton]

Where are you kids running the vent hose off the WUR when ditching the mailbox? Don't really like the thought if the diaphram blows out and pukes fuel all over the engine.

[Alan L]

I am not running one.
Hmmm.
Alan

[mark houghton]

Originally Posted by Alan L

I am not running one.
Hmmm.
Alan

Well shoot Alan, you're no help...at least not today!

[Alan L]

Nope. No help at all.
My car came with the K&N filter, and I had never even seen a 930 when I purchsed it over the internet. So I never knew anything different.
Now I am thinking I should fit a tube to at least dump to waste.
I did have a fuel leak once - I could smell the fuel in the engine bay after finishing a race. It was a cracked line at the FD head - where it exits to join the WUR. It had cracked and was spewing fuel in to the engine bay. That was a close one.
That line had a mod fitted to it - Google says it was a Mercedes fuel enrichment device. The vibration of that unit hanging off the FD/WUR line finally caused the line to crack at the union.
Could have ended badly.
Alan

[mark houghton]

Originally Posted by Alan L

Nope. No help at all.
My car came with the K&N filter, and I had never even seen a 930 when I purchsed it over the internet. So I never knew anything different.
Now I am thinking I should fit a tube to at least dump to waste.
I did have a fuel leak once - I could smell the fuel in the engine bay after finishing a race. It was a cracked line at the FD head - where it exits to join the WUR. It had cracked and was spewing fuel in to the engine bay. That was a close one.
That line had a mod fitted to it - Google says it was a Mercedes fuel enrichment device. The vibration of that unit hanging off the FD/WUR line finally caused the line to crack at the union.
Could have ended badly.
Alan

Scarey stuff that. Ideally I would plumb a line from the WUR to the air cleaner, to capture fuel in event of a failure. Alternatively, find some passage through the engine tin to vent directly to the ground. Just looking for what others have done...no need to reinvent the wheel so to speak.

[Alan L]

[52ndStreetAutoW]

Hey there,

Great question! Swapping out the stock airbox on the 930 for a K&N intake is pretty popular, especially among those looking to free up a bit of extra performance and clean up the engine bay. The major advantages typically include:

Improved airflow – The K&N system allows for better breathing compared to the restrictive factory airbox, which can translate to a bit more throttle response and power (though gains vary).

Reusable filter – The K&N filters are washable and reusable, which saves money over time compared to regularly replacing paper filters.

Simpler look and more space – The aftermarket setup usually opens up the engine compartment a bit, making it easier to work around.

As for the specific system, many go with the K&N RU-3510 or a similar cone filter combined with a custom or aftermarket pipe. Some even fab up their own brackets to get the fit just right. If you're still running the stock CIS (Continuous Injection System), be sure to get something that mates up cleanly without messing with airflow metering.

Just keep in mind – more airflow can mean more intake noise, and some purists prefer the original airbox for its OEM feel and sound dampening.

Hope that helps!

Sincerely,
Chris Hennessey
Founder of 52nd Street Auto Wash
Grand Rapids and Surrounding Areas, Michigan

[mark houghton]

Originally Posted by 52ndStreetAutoW

As for the specific system, many go with the K&N RU-3510

Nope. CIS intake on a 930 is 5 inches in diameter. RU-3510 is 2.125". So that pretty much leaves #5163 as the only option that I'm aware of.