YUp, I've been told the same thing, and I believe Vivid has actually Dyno'ed some of the various filters and the "benefit" wasn't worth it... These aftermarket filters aren't as good as the OEM at trapping dirt while allowing the most filtered air thru.

To the poster who asked if I noticed a difference, I can't say because the K&N was in the car when I bought it... I'll be ordering a VIVID dual snorkel setup this week when I call Dan. THAT will be a better use of money spent, since it will allow more readily available fresh air to be pulled in via the second snorkle and will retain the OEM BOX design, which I feel is supperior to the other designs out there... The surface area of the OEM filter is VERY large...

Mike

 

Actually if you get the dual snorkel from kevin he includes the bmc filter. There are lots of claims in this thread about what aftermarket filters do or don't do. They are all OPINIONS...none of you have any data....sorry. I am on bmc and no problems...

 

Kevin himself told me the stock filter offers plenty of flow due to it's large surface area. However, he does prefer BMC and discourages the use of K&N.

 

...And I'm not even sure why he prefers BMC over K&N... There are others out there as well... Amsoil sells them, other do too... Does one perform any better than the others??? Who knows... One thing I DO know, is that PORSCHE sells the paper filter and has tested it extensively in the car... If there was an advantage to an oil filled air filter, I'm pretty sure they would have spec'ed it... They didn't... THAT is fact.

Mike

 

Mike your logic is flawed....if Porsche would have spec'd the best components for our cars you would not have needed to upgrade anything...do you have the original DV's? ECU? Clutch?...I rest my case.

 

You been reading what Iv'e been doing lately???

Give me a few more weeks and I'll have it back to stock!

Mike

 

Someone here posted this earlier in another thread, hell if I can find it.

Posted in a Diesel forum, but clearly relevant here...

http://duramax-diesel.com/spicer/index.htm

While it doesn't specifically reference a "Porsche" air filter, it sort of says that the OEM has done their homework for you, on what performs the best. As was said, if Porsche thought the "XYZ" screen/oil filter was better, it would be in our cars.

 

K&N filter is half the cost of BMC and works great. They do work better then the stock paper filter as proven on the dyno and in throttle response. The only time the oil is an issue is when the consumer reoils it and OVER oils it causing build up on the MAF. Anyways... Mike look forward to the call Monday. Got tons of those so will give you the bro bro deal

 

As big a ***** as I've been for you lately, I'd expect nothing less...

I kid, of course...

Call you tomorrow...

Mike

 

At what power level does the stock paper filter begin to become a restriction?

 

By your post I thought you would have known.

 

vivid does the dual opening that you sell fit on the gt2 style decklid?

 

Dan- a filter's "job" is to filter. The marketing of K&N filters,( and AEM and BMC) focus exclusively on claims of power.

You perpetuate this marketing spin, but I'd expect no less. Nobody sells better than you, that's for sure.

I'd love to see a real filtration test (ISO5011) on K&N products, (and not dyno data that shows a few HP, possibly within the run-to-run variability of a dyno).

Oh, K&N published PARTIAL filtration test on their website- but only the parts that showed they were close- the stuff they omitted was telling. Problem is most readers are clueless. Since most read the K&N piece and come away impressed.

Here we go: http://www.knfilters.com/efficiency_testing.htm



Our actual air filters when tested generally demonstrate a cumulative filtration efficiency of between 96% and 99%. All this testing we do allows us to guarantee our air filters provide all the protection your vehicle will ever need.


Impressive? Not really- stock is 99.5%and above. And K&N fails to publish the majority of their data- lots of blather about methods, one sentence on results.

(I was the guy that posted this: http://duramax-diesel.com/spicer/index.htm ..read the K&N piece, then read the iso5011 results and you will see how woeful the K&N piece really is.)

Finally Dan, maybe you could post any test data (filtration, not dyno) you have on filters you are selling- if they are "better" as you say.


A

 

On this specific platform? No. However I do understand just how much air it takes to make say 700RWHP and the chances of a filter, airbox, or MAF designed for a vehicle making a max of about 450FWHP NOT being a restriction are pretty slim when power is raised by a third or more. If the car is stock then I doubt you'll see a restriction but as power climbs up past what the factory designed it for..... Hence my question, at what point is the OEM filter a restriction? The MAF? Better airboxes are being sold already - snake oil?

Paper filters meet what the manufacturer wants - low maintenance, good filtration to keep warranty claims down, followed by performance. Paper filters best but the downside is restriction. Make the paper one big enough for the HP target and your fine, raise that target and eventually you find a restriction. Hell not even all OEMs spec a filter big enough for stock engines. Getting a vac reading post filter and\or post MAF will tell you if you've hit a restriction at WOT.

P.S. Ard - the most intriguing thing in those tests from my POV is how quickly the aftermarket oil filters clogged up. I had seen CFM data in the past claiming that even "clogged" these filters flowed more air than most new paper filters. I don't think I've ever seen them claimed to filter more dirt however! As for OEM flowing all that the trucks can ask for - these are stock trucks yes? No one has flashed them to raise boost etc. right? Then that's not the audience for a performance filter IMO. Higher flowing drop in filters have to compromise to get higher flow rates - the compromise is filtering ability unfortunatly...

 

The current crop of airboxes being sold are not, in my opinion, any better, and some worse, than the OEM box. Here's why...

When you look at the stock box, what you see at the far left side is a port with a boss for mounting the MAFS. That port size does not change on ANY of the airboxes sold by ANY of the vendors I'm aware of. If you can't change that port size, then all the gain of any of the box designs will be lost at that single restriction point. If you want to change out the Tbody and some of the plumbing and do away with the MAFS, then you might improve upon the whole filteration of the inlet air. However, that requires a lot more investment in time, money, and software tuning.

That's why I'm such a fan of the dual snorkle design of the unit Kevin Sells at UMW and that Dan sells at Vivid. It keeps the OEM desing of the box, retains all the size of the oem filter, and allows for more air inlet into the box, which is the only improvement you can currently gain... Air feed and consistant storage.

Mike