Hallowed Cat?
Super Moderator
Joined: Oct 2002
Posts: 8,547
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From: MA
Hallowed Cat?
I believe you mean 'hollowed out'. I havent heard of a hallowed. It just means to pull that honeycomb innerds out. There really is no need for anyone to hollow one out. Its much better to buy a high flow replacement (just ask your computer, it will thank you later).
Rich
Rich
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Joined: May 2003
Posts: 67
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From: Toronto,ON, Canada
Hallowed Cat?
wheelMA1's right ... insatlled a high flow cat in my explorer & it's running smoother & everything........
If you option to hollow the cats out, you have to get O2 simulators to fool your computer those cost about US$80 each.
If you option to hollow the cats out, you have to get O2 simulators to fool your computer those cost about US$80 each.
Posting Guru
Joined: May 2002
Posts: 1,589
Likes: 1
From: AK
Hallowed Cat?
Actually, older trucks 87-96, don't have sensors after any of the cats, only on the manifolds. You could, without screwing up anything mechanically, chop off or gut/hollow the rear one and be fine. BUT its illegal and you will not pass emissions.
That said, I chopped off my rear one and have noticable performance gains and the sound is sweet! A highflow is on the way tho.
That said, I chopped off my rear one and have noticable performance gains and the sound is sweet! A highflow is on the way tho.
Fleet Mechanic
Joined: Sep 2002
Posts: 1,769
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From: Gretna ,LA.
Hallowed Cat?
the second one is a cat also, for cleaning up any emissions the first one missed. If the sensors is before the cat, removing the cat will probaly do nothing as far as setting off an engine code.
Junior User
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From: Toronto,ON, Canada
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