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Author Topic: Where Do I drill the two holes in my cat??  (Read 404 times)

Offline Charn Gill

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Where Do I drill the two holes in my cat??
« on: January 19, 2004, 01:38:26 pm »
im postin for clayton U. cause his comp crapped out. where exactly do you drill the holes on the cat?? remember sombody was talkin about this a while ago. (to pass aircare).
thx.
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Offline Marty van den Bosch

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Where Do I drill the two holes in my cat??
« Reply #1 on: January 19, 2004, 02:33:23 pm »
One behind each ear is best. But the cat will scratch you up bad until you get the first hole done.


I believe they should go one to either side of the front face of the catalytic converter on the intake side of it.
I think the idea is to suck clean air in, not to blow echaust out, which is why no holes go on the bask side.
Jordan Gladman knows for sure however.
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Offline Sarah Hancock

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Where Do I drill the two holes in my cat??
« Reply #2 on: January 19, 2004, 03:29:32 pm »
Quote from: "Marty van den Bosch"

I think the idea is to suck clean air in, not to blow exhaust out


Considering a cat works most efficiently when the temp inside is high, I still don't understand this ram-air idea...
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Offline Mike Schmid

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Where Do I drill the two holes in my cat??
« Reply #3 on: January 19, 2004, 07:04:08 pm »
I believe the holes allow for fresh air to enter the cat, the oxygen in this air increases the efficiency of the cat by speeding the reactions in it.  Mind you, I'm no chemist and I don't really care about cats.  However, it could just lower the PPM by adding fresh air with no polutants... But alas... lots of older cars have air pumps (smog pumps) on the accesory drive that pump air into the cat through hoses from the engine bay.
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Offline Jordan Gladman

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Where Do I drill the two holes in my cat??
« Reply #4 on: January 20, 2004, 01:27:08 am »
you'll find a lot of cats with a metal tube coming off the side (oxygen injection)

it puts air in the exhaust to mix with the unburnt fuel, which helps it burn a bit more... this some how makes sense to me... and it worked on jared clarks car...

we drilled 2 holes on the very front of the cat and he passed...
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