Gonna set in a straight pipe...cuz curious as to how loud the v8 rumble will be before I fit new box.
dont some peeps make up dummy cats?
its TOO NOISY with straight pipe in-lieu of cats. So I cut open the cats to find the ceramic honeycombs had broken-up/moved and caused blockage in centre box. have welded up cat boxes but now left with a terrible tin-tingling noise on acceleration. Gona have to source new/replacement downpipes/cats.
I note there are two types: 94-99 and 99-02 the latter one being 100 pounds more expensive ! my RR is model yr 2000 - 4.0 v8 and the downpipes/cats fitted have only pre-cat lambda sensors ( one each side ). Anyone know if the cheaper 94-99 downpipes will do and who is cheapest supplier ?
I note there are two types: 94-99 and 99-02 the latter one being 100 pounds more expensive ! my RR is model yr 2000 - 4.0 v8 and the downpipes/cats fitted have only pre-cat lambda sensors ( one each side ). Anyone know if the cheaper 94-99 downpipes will do and who is cheapest supplier ?
StuckAgainSteve
Well-Known Member
You should wear full breathing equipment if cutting catalytic converters open, then vacate and air the place used for cutting for a period. Cover any bare skin with barrier cream plus disposible clothing. There will be lots of heavy metals flying around if the cutting disc so much as brushes the core of the cat. Then vacate and air the place used for cutting for a period. Even washing the casing out will pollute the water system with heavy metals - in reality what I'm saying is - don't **** about cutting cat boxes open! 
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You should wear full breathing equipment if cutting catalytic converters open, then vacate and air the place used for cutting for a period. Cover any bare skin with barrier cream plus disposible clothing. There will be lots of heavy metals flying around if the cutting disc so much as brushes the core of the cat. Then vacate and air the place used for cutting for a period. Even washing the casing out will pollute the water system with heavy metals - in reality what I'm saying is - don't **** about cutting cat boxes open!
Yeah always better to be safe than sorry. Don't want to damage your health. So better to get the wife or one of the kids to do it for you.
I note there are two types OF FRONT DOWN-PIPE/CATS: 94-99 and 99-02 the latter one being 100 pounds more expensive ! my RR is model yr 2000 - 4.0 v8 THOR and the downpipes/cats fitted have only pre-cat lambda sensors ( one each side ). Anyone know if the cheaper 94-99 downpipes will do? Am I right in thinking the real difference is in the size of lambda sensor fitted... the older type being 12mm and the later type OBD ?
I have a glasspack on mine in place of the center muffler. It gives off just the right amount of noise with out being obnoxious.
StuckAgainSteve
Well-Known Member
Does anyone know the diameter of the centre box pipework? (Thor 4.6)
Thinking of making a bit more noise myself!
Thinking of making a bit more noise myself!
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Does anyone know the diameter of the centre box pipework? (Thor 4.6)
Thinking of making a bit more noise myself!
The center muffler itself or the inlet or outlet pipes?
StuckAgainSteve
Well-Known Member
The pipes. Thinking of buying a suitable Turbo Muffler or Cherry bomb to replace the centrebox - to give the old girl a bit of a V8 burble.
The pipes. Thinking of buying a suitable Turbo Muffler or Cherry bomb to replace the centrebox - to give the old girl a bit of a V8 burble.
2.5 inches for both the inlet and outlet. I have a 28 inch long glasspack and that seems to be a good length.
StuckAgainSteve
Well-Known Member
Think up to 99 pipes had 12mm and the later pipes had 18mm lambda's
I want to de-cat my year 2000 4.6 so investigating using custom exhaust parts from Merlin Motorsport race parts, accessories, spares & equipment they do all sizes of adapters etc. I have in my garage front pipes from a 4.0ltr 98 car which has four lambda's not sure of size, will check. The down pipes to and after the cats are 2 inch. Haven't had the chance of checking the diameter of the pipes on the 4.6. Modifying the 4.6 pipes makes sense as they have the correct two lambda holes at 18mm. I also intend putting a double sleeve joint in the cross over to prevent having to take the cross member out. The replacement pipe for the cats will need bending. Anyone done something like this?
Of course it won't pass MOT test if you do that.
