Philb714
Active Member
I was bored (I get bored easily)..... So I thought I would 'de-cat' the standard headers that I had hanging about in the garage after fitting some Arrow headers.
Keyhole surgery was required I thought, so pass the forceps Doc....
I started off using (several) metal cutting discs on my Dremel (Using a hacksaw to just cut through the center welded part to make it easier) and make a 'guesstimate' of where the Cat would be located..
There are two metal skins... the outer skin which I cut through with the Dremel.
And a second skin which I think is stainless steel which was really hard to drill through using a standard HSS drill bit, maybe a cobalt drill bit would of been better... it probably would of, but I didn't have one.
I drilled the depth of the drill to get right through the cat honeycomb underneath... you'll see why later... (I'd probably recommend wearing a mask as it gets a little dusty & gloves if you're worried about your skin and all that Health & Safety bollocks).
Be careful if you do this job as the metal swarf from the drilling and the honeycomb material that the Cat is made of is very sharp.
Once I'd chain drilled the second skin, carefully dragging the drill sideways to correct my shite 'close linked' holes, I then levered the plate up with a screwdriver revealing the honeycomb. I used the drill again to get right down through the Cat to the other side, then joined all the drill holes together. Note: I had to 'lean' on the drill as it was hard work drilling through the Cat.
It was then a case of digging the center out with flat bladed screwdriver & a metal cold chisel with the use of a hammer. If you are lucky, you can break through the ends of the Cat honeycomb quite easily to clear a path at both ends. The headers are very 'robust' so you can use a fair bit of force to dig the Cat out.
I used a magnet to fish out all the smaller bits & pieces.
Bit more digging required...
Once I had cleared the center out, I used a chisel just to part the inner skin from the honeycomb then used a small crowbar to tease out the side sections of the Cat.
Getting the loose Cat section out was a faff, but with a bit of brute force and ignorance it came out... If I'd made the hole bigger it might of made it easier.
It was just a case of cleaning out the remaining bits of honeycomb then (Crowbar was the best tool to use).
Keyhole surgery was required I thought, so pass the forceps Doc....
I started off using (several) metal cutting discs on my Dremel (Using a hacksaw to just cut through the center welded part to make it easier) and make a 'guesstimate' of where the Cat would be located..
There are two metal skins... the outer skin which I cut through with the Dremel.
And a second skin which I think is stainless steel which was really hard to drill through using a standard HSS drill bit, maybe a cobalt drill bit would of been better... it probably would of, but I didn't have one.
I drilled the depth of the drill to get right through the cat honeycomb underneath... you'll see why later... (I'd probably recommend wearing a mask as it gets a little dusty & gloves if you're worried about your skin and all that Health & Safety bollocks).
Be careful if you do this job as the metal swarf from the drilling and the honeycomb material that the Cat is made of is very sharp.
Once I'd chain drilled the second skin, carefully dragging the drill sideways to correct my shite 'close linked' holes
, I then levered the plate up with a screwdriver revealing the honeycomb. I used the drill again to get right down through the Cat to the other side, then joined all the drill holes together. Note: I had to 'lean' on the drill as it was hard work drilling through the Cat.It was then a case of digging the center out with flat bladed screwdriver & a metal cold chisel with the use of a hammer. If you are lucky, you can break through the ends of the Cat honeycomb quite easily to clear a path at both ends. The headers are very 'robust' so you can use a fair bit of force to dig the Cat out.
I used a magnet to fish out all the smaller bits & pieces.
Bit more digging required...
Once I had cleared the center out, I used a chisel just to part the inner skin from the honeycomb then used a small crowbar to tease out the side sections of the Cat.
Getting the loose Cat section out was a faff, but with a bit of brute force and ignorance it came out... If I'd made the hole bigger it might of made it easier.
It was just a case of cleaning out the remaining bits of honeycomb then (Crowbar was the best tool to use).
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