Which aftermarket air filter/high flow air filter? 97 2.5 boxster

[markPR]

Hi, I have recently purchased a 1997, 5 speed manual, 2.5 Boxster, RHD (in the U.K) and I want to upgrade the stock air filter to make the engine sound a bit more throatier/deeper. I have read about the Evo high flow air system but I do not want to spend that much money on an air filter incase its makes little difference to sound. I have also seen cheap K&N and other branded replacement panel filters, but I do not really know what to go for.

Any Help and/or suggestions would be highly appreciated

Thanks, Mark

Edited March 13, 2010 by markPR

[1schoir]

Mark:

Be particularly careful with aftermarket air filters that require oiling.

The early 986's have an Mass Airflow Sensor (MAF) that is very sensitive to fouling and will also throw a CEL. The later MAF's have a different design and are thus less sensitive, however your DME must be reprogrammed to accept the later style MAF.

Regards, Maurice.

[pk2]

I've followed this topic over the years and it's been pretty controversial. A lot of knowledgeable people have piped in though. The conclusion I came to is that you buy absolutely nothing with an aftermarket air filter. Even the direct, cool induction filters from K&N do nothing performance wise. It's just like after market headers, nada, just sound.

You should do a search on the subject.

Regards, Pk

Edited March 13, 2010 by pk2

[infocusf8]

There is a lot of discussion regarding the stock filter being replaced by aftermarket filters primarily the reusable oil type filters. I was trying to find a link that I read about filters for you but couldn't. The gist of the article concerned testing done on filters to see what happens when you use a filter that allows more air through giving you a little bit deeper sound versus the OEM paper filter. The sacrifice that is made for the little bit deeper sound with the reusable filters is more particulates get into your combustion system that can shorten engine life. I switched to a K&N for about 7K miles and after I saw the amount of stuff in the air box that had gotten through the filter and read the MAF problems encountered I went back to an OEM filter. After reading about all the issues that third party accessories can cause on Boxsters I've come to the conclusion that the German engineers that designed the car knew what they were doing.

[markPR]

Thanks for the advise and comments guys. I must admit that after the past few days researching this and talking to a few other people that own boxsters, I too, have came to the conclusion that the stock air filter is the best solution because of the MAF and fouling issues associated with the aftermarket filters. I think I may just install new stainless headers and an aftermarket muffler if I want a deeper sounding boxster.

Thanks for your help,

Mark

[infocusf8]

Thanks for the advise and comments guys. I must admit that after the past few days researching this and talking to a few other people that own boxsters, I too, have came to the conclusion that the stock air filter is the best solution because of the MAF and fouling issues associated with the aftermarket filters. I think I may just install new stainless headers and an aftermarket muffler if I want a deeper sounding boxster.

Thanks for your help,

Mark

Mark you might find it less expensive to have baffles removed from your stock exhaust if a deeper sound is all your looking for and that would accomplish it and not cause you any smog check problems down the road. You might also remove the snorkel on the intake side (about a 10 minute job) and see if the intake sound is more to your liking. I don't know that headers are going to give you a better sound and the HP gains from headers over stock exhaust are also negligible. As archaic and cheap as the stock headers look functionally they accomplish what they are supposed to do very well. The main thing actually gained by an aftermarket exhaust system is weight loss which will increase performance but when you consider the gain versus expense most times it is not worth it unless you've just got money to burn.

[Gary H]

There's a few things I'd like to add here.

Does anyone have proof of oiled filters contaminating MAFs? At what speed would air need to be hitting a filter for it to force the oil off and down the tract?

I'm sorry but the sheer number of people of chime in with 'oh it's not MAF-friendly' because they've heard some ones friend of a friend 'who's an engineer' mention it....Jeez!! :D

Anyway, if you're interested, see what K&N themselves say on the subject:http://www.knfilters.com/MAF/massair.htm

For more noise, there are two things you can do:

1) "De-Snorkel" This is a 10 minute job and get's rid of the funnel that directs (albeit slowed-down, hence quieter) air into the air box.

2) Buy this kit, or make one:

The roar from 4.5K is intense :D

[markPR]

That kit looks interesting, where can I get it from?

I think I will have a go a de-snorkling aswell, although I am having real trouble getting the intake covers off the car

Edited March 14, 2010 by markPR

[1schoir]

There's a few things I'd like to add here.

Does anyone have proof of oiled filters contaminating MAFs? At what speed would air need to be hitting a filter for it to force the oil off and down the tract?

I'm sorry but the sheer number of people of chime in with 'oh it's not MAF-friendly' because they've heard some ones friend of a friend 'who's an engineer' mention it....Jeez!! :D

Anyway, if you're interested, see what K&N themselves say on the subject:http://www.knfilters.com/MAF/massair.htm

...............

K&N is hardly an unbiased source. Here is their "consumer protection pledge":

K&N pledges to our customers that they will not be taken advantage of and charged for a repair due to a dealership warranty denial blamed on the presence of a K&N product.

While the oil may not be the cause or the only cause of the fouling, Porsche itself believed that the early MAF's design was prone to malfunctioning enough to have issued a TSB on the matter and to change the design of the MAF.

As for K&N, I would feel so much better if their consumer protection pledge read as follows instead:

K&N pledges to our customers that if their MAF fouls shortly after installing one of our K&N filters according to our instructions, K&N will replace it at no charge...No questions asked.

That wording would give a lot more confidence than their reliance on the protection already offered to consumers under the Magnusson-Moss Warranty Act.

Regards, Maurice.

[infocusf8]

I would be willing to bet that most MAF fouling from oiled filters is caused from the owners over oiling them after cleaning. I've used K&N before and found that less is more when it comes to the right amount of oil on them.

[mcmike27]

Mark, we have a 98 986 that had the baffles removed. It sounds great! Simple job...a local Porsche shop dropped the OEM original muffler cut the top off and removed the baffles then welded the top back on and reinstalled the original. Let's just say you HEAR this car now before you see it. I LOVE it..the wife well lets just say she likes it when I get past 2700 RPM. I also use the standard stock air filter and I have had no issues. I will be de snorkling mine as soon as the weather permits as we dont drive it around in downpours.

It you have any questions let me know.

Thanks for the advise and comments guys. I must admit that after the past few days researching this and talking to a few other people that own boxsters, I too, have came to the conclusion that the stock air filter is the best solution because of the MAF and fouling issues associated with the aftermarket filters. I think I may just install new stainless headers and an aftermarket muffler if I want a deeper sounding boxster.

Thanks for your help,

Mark

[1schoir]

Thanks for the advise and comments guys. I must admit that after the past few days researching this and talking to a few other people that own boxsters, I too, have came to the conclusion that the stock air filter is the best solution because of the MAF and fouling issues associated with the aftermarket filters. I think I may just install new stainless headers and an aftermarket muffler if I want a deeper sounding boxster.

Thanks for your help,

Mark

Mark:

Must reading before you jump into a headers install on a '97:

www.ppbb.com/phorum/read.php?19,1552140

Regards, Maurice.

Edited March 19, 2010 by 1schoir

[markPR]

Mark, we have a 98 986 that had the baffles removed. It sounds great! Simple job...a local Porsche shop dropped the OEM original muffler cut the top off and removed the baffles then welded the top back on and reinstalled the original. Let's just say you HEAR this car now before you see it. I LOVE it..the wife well lets just say she likes it when I get past 2700 RPM. I also use the standard stock air filter and I have had no issues. I will be de snorkling mine as soon as the weather permits as we dont drive it around in downpours.

It you have any questions let me know.

Yes I would be interested to know exactly how it sounds because I'm not after an over the top deafening rumble, lets justs say, something that will turn a few heads when you put your right foot down. You could hardly send me a video or sound clip by any chance? My local exhaust specailist would be able to do this easily I presume?

Thanks, Mark

Edited March 20, 2010 by markPR

[markPR]

Maurice, after reading your link, I will definitely not be changing the stock headers, thats for sure.

Many Thanks, Mark

[1schoir]

Maurice, after reading your link, I will definitely not be changing the stock headers, thats for sure.

Many Thanks, Mark

Mark:

Probably a wise decision. Unless one is prepared to deal with the distinct possibility that one or more of the exhaust manifold bolts will snap off, it's a good idea not to go there. I think that with more recent vintage cars, and with those that have not been driven in harsh environments (snow, salt, etc.) there is a good chance that none of the bolts would break off. The older and the more mileage, the less likely one can have an uneventful install.

There's another guy on 986forum (his handle is "eightsandaces") who went through a similar ordeal with "only" two broken bolts. At one point he was so despondent that he was actually just going to "dump the car". Fortunately, he mustered some courage, applied himself, and succeeded in accomplishing the header install. He had to use two TimeSerts, but he got it done and is very happy with the results:

http://986forum.com/forums/showthread.php?t=23888

It makes for interesting reading.

For me, it was definitely worth it. Every time I put my foot in it at about 3500 rpm, the headers and PSE combination make the sweetest music (not too loud, not too quiet, very mellow, throaty sound), but I probably would not have done it if I knew what might happen. Definitely a learning experience.

Regards, Maurice.

[mcmike27]

Mark, sorry I didnt see your reply until now. I will get a little video or sound clip and try and post it. My son can do that pretty easily with his cell.....and yes a competent exhaust shop can do this easily. Also I 'de snorkeled' our 986 last Thursday and aside from the fact that it weighs a little less I cant hear nor feel and difference in performance. It does make a little more of a 'suck whooosh' sound under spirited accleration now. Send me a PM here and we will try and get that clip asap. The weather should be good the next 3 days for us here in Pa.

m2

Mark, we have a 98 986 that had the baffles removed. It sounds great! Simple job...a local Porsche shop dropped the OEM original muffler cut the top off and removed the baffles then welded the top back on and reinstalled the original. Let's just say you HEAR this car now before you see it. I LOVE it..the wife well lets just say she likes it when I get past 2700 RPM. I also use the standard stock air filter and I have had no issues. I will be de snorkling mine as soon as the weather permits as we dont drive it around in downpours.

It you have any questions let me know.

Yes I would be interested to know exactly how it sounds because I'm not after an over the top deafening rumble, lets justs say, something that will turn a few heads when you put your right foot down. You could hardly send me a video or sound clip by any chance? My local exhaust specailist would be able to do this easily I presume?

Thanks, Mark