Date: Wed, 15 Apr 1998 12:17:22 -0400
Reply-To: "Eric B. Pickering" <pickering.14@OSU.EDU>
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: "Eric B. Pickering" <pickering.14@OSU.EDU>
Subject: Re: K&N filters (Dyno'ed '71 911 +4hp)
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>
>>I'm sure they would not be so hooked on them, from Baja racers to
>>formula cars, if they felt they would pass any size particulates (silica
>>or whatever) that would scuff their rings/barrels to any signifacant
>>measure.
>
>
>You will be hard pressed to find an informed person with a turbocharged
>vehicle running a K&N on a normal streetable vehicle, particularly one who
>wants over 100k out of the turbo (no reason why 200k isn't possible even on
>something like an early air cooled Audi turbo with regular oil and air
>filter changes). Remember engines (bearings) are a lot more durable than
>turbos, this basically is all I said. IMHO no way you are getting the
>filtration of quality German OEM pleated filter, but it probably isn't even
>an order of magnitude difference so the potential trade is up to the
>individual, a few barely percieved hp, the kind of thing you might simply
>get from say warm day to cool day or doing the damndest to prolong the life
>of expensive hardware. I'll note even K&N's literature made no superior
>filtration claims when last I looked extensively (4 years ago with the G60.)
>Sure racers, nearly every NASCAR car running, and the like use em daily, and
>rebuild often for other reasons. And in admission I use one on the Scirocco
>and have on most of my normally aspirated inline 4 VW's, but those are cheap
>engines, and frankly I'm probably not seeing much increase in performance,
>I've been meaning to run some comparisons on a friends chassis dyno but have
>never found the time. I guess that is where it sort of boils down, VW
>engines are durable, real durable and when normally aspirated probably
>capable of runing extreme times with even totally inadequate filtration, but
>it comes down to your call, on the G60 I was anal, on a normal 1.7 I'm not,
>but I likely imagine any improvement. And still on 911 engine if I were
>paying $1500 or more for a set of pistons and liners, and being air/oil
>cooled, I'd run the best damn filtration available every day and the hell
>with a few hp, the way I drive more track time would be a better benefit
>than a bit more power.
>
>John
Again, some good points. It is all in what trade offs you want to make. I
do take a bit of issue with the statement,"barely perceived hp". I think on
most cars, including my 911 (again with approx. 165 hp), a 4hp increase is a
lot. If you had a switch to flick in your car that would turn on 4 more
horse as you moderately excellerated you'd probably think you hit a mild
turbo boost. Try driving down the road while someone only slightly changes
your timing, you'll see the huge difference a few less horses make (well,
maybe don't do that but you get my point).
I do run synthetic oil in my 911 and Vanagon, changing it at the standard
intervals if not sooner. Also, we aren't really talking here about 911s,
are we? It isn't as costly to repair a wasserboxer as a 911 engine AND 4hp
is a ton on top of 90, IMHO. For me the trade off would be worth it (again,
I'm going under the ASSUMPTION that there is an increase in perf. for the
Vanagon!).
Eric
P.S. 911s are BULLETPROOF, yes that doesn't mean they don't break or
wear-out but, they aren't the most successful endurance racers for no
reason. They do last even under incredibly adverse conditions. Oops, not
Vanagon talk, sorry.
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