Hi All
Just bought a petrol 2006 4.4 AJV8 Range Rover. The PO said the cats were stolen, and he's done an awful bodge with some "Straight" pipes and lots of gungum. I'd like to replace the cats, but apart from OEMs costing 1k each, nobody seems to have them in stock. I've had a look around ebay, and it seems that cats for the BMW engined ones can be had for about £400 each. So I'm wondering if I could use those with a bit of fettling to fit. With BMW and AJ both being 4.4V8s if figure they must have similar flow capacities. Experienced thoughts would be much appreciated. Thanks

You can get universal performance cats, so just get a pair of an appropriate size.

It might be worth ringing round local breakers to see if they have any used but serviceable cats - they don't need to be brand new, as long as the scrapper is a crash damage (if the engine's gone the cat might have overheated and be scrap).

Nodge68 said:

You can get universal performance cats, so just get a pair of an appropriate size.

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Thanks - appreciate the advice - definitely an option. Main thing for me is having it smelling clean as I live in the city and know how nasty it is to walk or cycle behind something chucking out fumes. Any recommended manufacturers?

jwrrc said:

It might be worth ringing round local breakers to see if they have any used but serviceable cats - they don't need to be brand new, as long as the scrapper is a crash damage (if the engine's gone the cat might have overheated and be scrap).

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Definitely worth a look - thank you

DaveyRangie said:

vice - definitely an option. Main thing for me is having it smelling clean as I live in the city and know how nasty it is to walk or cycle behind something chucking out fumes.

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You're driving the wrong vehicle to have those sort of concerns.

The CATs are there to convert CO into CO2 and water, but it won't stop it smelling of a petrol engine.

Nodge68 said:

You're driving the wrong vehicle to have those sort of concerns.

The CATs are there to convert CO into CO2 and water, but it won't stop it smelling of a petrol engine.

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hahaha - fair point I'm going to get it on a ramp this week to have a proper look at the bodge and see how much welding I have to do...
Got a feeling that the O2 sensors are probably missing as it smells like its running very rich - or is that normal without cats? I remember my old Triumph TR6 smelling much less "Cokey"! Many other little jobs on the list... Learning curve...

Appreciate the feedback

DaveyRangie said:

Got a feeling that the O2 sensors are probably missing as it smells like its running very rich - or is that normal without cats?

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That's normal if it's got no cats.
The cats require a rich fuel mixture to work, which is why the fossil fuel industry pushed for their inclusion on vehicles back in the 70s.
A cat equipped vehicle uses about 20% more fuel than the same vehicle, which is calibrated to run without cats.
It was the fuel industry scam of the century.

Nodge68 said:

That's normal if it's got no cats.
The cats require a rich fuel mixture to work, which is why the fossil fuel industry pushed for their inclusion on vehicles back in the 70s.
A cat equipped vehicle uses about 20% more fuel than the same vehicle, which is calibrated to run without cats.
It was the fuel industry scam of the century.

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Interesting and enlightening..I am rather inclined to go down the rabbit hole - but I hadn't taken the red pill on that one yet! it does seem that there's very little that isn't a scam these days

DaveyRangie said:

Interesting and enlightening..I am rather inclined to go down the rabbit hole - but I hadn't taken the red pill on that one yet! it does seem that there's very little that isn't a scam these days

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Ford were developing a lean burn engine that used a lot less fuel, that was scotched by the move to inefficient cats which only modify the pollution and in so doing actually create more pollution

DaveyRangie said:

hahaha - fair point I'm going to get it on a ramp this week to have a proper look at the bodge and see how much welding I have to do...
Got a feeling that the O2 sensors are probably missing as it smells like its running very rich - or is that normal without cats? I remember my old Triumph TR6 smelling much less "Cokey"! Many other little jobs on the list... Learning curve...

Appreciate the feedback

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If the lambdas are missing you'd have the engine light on.
They help the ecu monitor your engines emissions and the cats final emissions.
The ecu runs the mixture lean and rich to promote the cars burn cycle.
That's why the live data for lambda sensors should lift and drop.

Have you done anything with this yet? Can I see a pic of the pipes?

Hi Guys

sorry for radio silence...

So, I finally went with some magnaflow aftermarket cats. Thin stainless welding in awkward positions isn't yet in my skill-set, so I had a local tuner/fabricator place fit them - was also nice to support a local cash-only business (Gotta keep it alive!). I got the cats from a place in Berlin via ebay as magnaflow don't seem to be sold here. Approx £400 for the pair versus £2500 from Landrover! Euro 5 emissions quality. The service was exceptional - the guy called me once I had ordered and was on the phone for half an hour to make absolutely sure that I'd ordered the right ones - turned out that I needed to go a size up. Was also cool as he was a fellow enthusiast and was running an L322 and a P38 himself, so was definitely speaking from experience. They're called German Autobahn on ebay.

So Cats done, £350 for some difficult welding, went for a run and still an occasional "Rich" smell in the cabin and still idling at 1500rpm. Tempted to start cursing the exhaust fabricators. Checked the work for leaks - all good. Hmmm. Left it for a couple of days during which time the phrase "Check the MAF sensor" kept nagging from the back of my mind. Eventually I gave in and lifted the bonnet, checked around the air intake, and lo and behold, found a split crankcase breather pipe just downstream from the MAF. Fortunately it was split just at the top union so was easy to cut off the damaged 3/4", shove the remainder back on the spigot and tighten the jubilee clip.

Job done. Idling at 500rpm, not stinky, happy as Larry. Invested in a OBD 2 scanner, cleared some codes, and all is good for now.

Have fixed a couple of windows and halted some rust. Lots of other jobs to do.

Really appreciate the advice and patience from you all

Nice one

DaveyRangie said:

. . . . . . . was running an L322 and a P38 himself, so was definitely speaking from experience. They're called German Autobahn on ebay.

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Can you post link to his eBay shop. Will be interesting to see how much to replace my stolen cats on project P38.

ere ya go: https://www.ebay.co.uk/str/fastforwardperformance