I'll be needing to replace the stock filter on my TR soon and I was looking at getting the k&n drop in filter. I looked it up on k&n's website for the part number and it gives the same part number for both the wrx and STI. Now that the wrx has a 2.5 does that mean it's using the same filter as the STI? I just want to make sure I buy the right filter. It's saying part number 33-2232. Should I even bother with the k&n? Should I go with a factory filter or aftermarket like fram? I read somewhere a few months ago that the stock filter flowed better than the k&n but still most posts I've looked at said to go with the k&n or perrin drop in filters.
The K&N will flow much better than stock. You'll actually be able to hear the turbo and RC valve very well, especially if you have a silencer delete. Thin intake box assembly hasn't changed since the WRX came to the US. The filter for my 03 is the same as the one for my 06 STi.
Yup, thats the right part number, I just bought one for my 06 wrx. You might want to look into the Perrin though, it seems to be popular, and is much cheaper then the K&N. I paid $55 for my K&N, which seems like a lot for a drop in filter.
I tell ya, this forum has got to be the best ever. I just did my silencer delete mod this weekend, and it sounds great. No CEL or anything. I phoned my local part store, and they dont have anything on file for K&N p/t #'s for my 06, so the first thing I was going to do this morning was search on here to find the p/t #. No need to now, this thead was the first thing that came up as a new post. Gotta love when fellow WRX owners are thinking on the same wave length.
I have a K&N drop-in for my '05 STi. I didn't notice any increased noise or any real gain in performance. I'm sure it's better than a stock paper drop-in but....
If there is a performance gain, it's not really noticable. Some people say they get better throttle response. The only way it'll be really noticable is on a modded car on the dyno, especially one with a bigger turbo. I bet there's a few HP difference between stock and a good aftermarket.
Thanks guys. I guess I'll just order the k&n filter. I'll check the perrin filter but isn't it a foam filter? I heard foam filters weren't good as they deteriorate and the pieces get sucked into the engine. Thanks again
Is the part # for my 06 WRX:33-2232 or is it 33-2075. I read this post a few days ago, and double checked the first number on the K&N website. Everything seemed good, so I got my parts guy to order it in. I'm going today to pick it up. If its not the right one, I'm going to be totally ripped.
I'm going to look again on the K&N website and check both numbers.
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