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Re: Blow hole filter?

To: "Marc Sayer" <msayer1@concentric.net>
Subject: Re: Blow hole filter?
From: Ronnie Day <ronday@home.com>
Date: Mon, 23 Oct 2000 23:57:37 -0500
>>Gordon Glasgow wrote:
>> 
>> Mine's a K&N but I don't know the part number. It's been on there for 
years. Not really a good idea,
>> BTW. It's good to have some vacuum to vent the cam cover. I only did mine 
because the aftermarket
>> air cleaners didn't have a fitting for the hose.
>
>Gordon is right on about this. If your car wasn't originally designed
>for venting the crankcase to atmosphere (i.e. it vented to the air
>filter, a pcv system or some other low pressure or vacuum location) then
>you really can't just stick a filter on the valve cover and call it
>good. The reason is that the vent area will not be sufficient to prevent
>pressure buildup in the crankcase without the vacuum. You need much more
>vent area when venting to atmospheric pressure than you do when venting
>to vacuum.

<snip>

I realize this was originally posted a couple of months ago, but I'm just 
now getting through the backlog. In addition to the little K&N breather 
tube filters (already mentioned) that I bought with the primary SU 
filters and velocity stacks, I also bought a couple of fittings that are 
designed to allow you to attach about a 3/4 (ID) hose to an air cleaner 
housing that didn't originally have fittings. Realizing that you might 
need to use a "T" and connect to the air cleaner base on both carbs in a 
dual (either SU or Solex) setup, would it be better to do run a vent hose 
from the valve cover to one or both of the A/C assemblies rather than 
using the small open element filter?

I know the L-motors have a baffle inside the valve cover that blocks 
direct access to the outside, and I don't think there's any sort of valve 
or filter inline with the hose going to the stock air cleaner. The dump 
into the air cleaner housing is outside the filter element, if my memory 
is correct. How can we set this up using the open element style air 
cleaners?

FWIW,
Ron


Ronnie Day
ronday@home.com
------------------
Dallas/Ft. Worth
------------------
'71 510 2-dr (Prepared Class Autocrosser)
'73 510 2-dr (Street Toy)


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