Contemplating the conversion from cat to no cat of a Canadian model. European deliveries 1986/1987 didn’t have a cat, please correct me if I’m wrong. Is this possible? If yes is it troublesome? What is needed to be done apart from installing the downpipe no cat instead of the one with cat? Apparently the emissions are somehow higher then the onrs imposed by regulations.
I would think you need to add a threaded hole to the non-cat downpipe for the oxygen sensor.
David
If that’s in the 3-1 manifolds the europeans have the threaded hole too. Emissions higher but some jurisdictions are able to live with it. Or so they say…
IIRC, David, it’s below the cat.
David
Chris,
converting is dead easy as no European SIII car was ever fitted with cats and the spares supply with consumables including the exhaust system is superb. You just order from the catalogue.
The problem is: will your authorities accept the swap. 1987 vintage will hardly qualify for no-emissions-requirement, I’d guess. Where I live they do an exhaust sniffing test every other year and you wouldn’t achieve the cat-version emissions without a catalyst converter. YMMV.
Good luck
Jochen
75 XJ6L 4.2 auto (UK spec)
I welded the o2 sensor bung into by downpipe- but it was a Bells stainless downpipe. I also got the Bells Y pipe to get rid of the secondary cat as well.
That location works well, sniffs both ‘banks’ and is in a low pressure area so as to not obstruct flow. Of course, it clears everything, can be easily changed, and the stock wiring reaches so no other modification is required.
Jochen, you’d be surprised at what you can get away with over here. Even my 2001 Toyota pickup is emissions exempt now (20 year limit on testing).
Thank you all for your input on this. So good to feel “home”.
Since I 'm requested to bring the car to European / Austrian specs, I had to do the lights conversion even if minimal, I thought why not make it for the exhaust too as I was contemplating buying a downpipe with cat as the readings suggest the cat is clogged (and that’s a bummer because the car is still under 30k miles).
I would change the whole exhaust. One end can has a hole in it and the middle pipes look on their last days of life.
My concern was any modification needed on the intake side to counter or match the free flow on the exhuast part, any tunning needed for the car central unit or whatever the engine management resides on or does this takes care of itself and adjusts automatically.
The car will be registered as historical and wont be driven intensively and I won’t pollute anymore than any other SIIII on the road.
@paetersen, where do you live?
Any suggestions for the best place(s) to shop for the exhaust system, Europe preferably due to the size and cost of shipping / taxes.
Thank you again.
Aquilla, I’m in New England, USA and it sounds like you are in the EU? I have the US spec downpipe that came off my car, with good cat and O2 bung, it’s listed in the Classifieds section. If you are in Europe shipping would probably make it impractical though. If you want, PM me and I can get a shipping quote. But, if you don’t need to run a cat, I’m pretty pleased with the Bells system, and it’s quite resonable price-wise. I got mine from SNG Barratt.
I’m in EU, that’s correct. I will go with stainless steel, the only question is if I stay with cat or I bring it to the European specs, no cat hence more power and more relaxed emissions control. That makes a lot of sense to me.
Is there anything to change/adjust apart from the exhaust hardware and the O2 / lambda sensor
You probably have an air injection plus plumbing to get rid of, and required ignition timing might change.
**
There is no need for the O2/Lambda sensor in the European set-up, Chris - it was there principally to protect the cats. Basically the Lambda is not active until the O2 sensor reaches 400C during warm-up - and is not ‘active’ during acceleration anyway. It’s not really a fuel saving item…
Also, the ‘European’ set-up was used with ‘manifold’ rather than the US ‘ported’ vacuum - requiring a different ign advance setting, giving more max power…
Frank
xj6 85 Sov Europe (UK/NZ)
**
My 1986 Series III Sovereign V12 actually does have a catalictic convertor.
Don’t know about the “sixes” though…
My Xj12 was produced for the German market. Actually it is one of very few 1986 model cars that apply for a green “Feinstaubplakette” (environment protection sticker), which allows me to drive it into a lot of German cities that were otherwise banned for cars of this age…
Can‘t you get into these stupid zones as a foreigner with a car clearly qualifying for a H number which would be exempt from the ban?
People I know risk it, unless they need to do it frequently.
Hi David,
As I live practically on the border and go to Germany for the elixer of life for my V12 (Shell V-Power Racing), the risk of getting stopped is too high compared to the cost of the sticker ( €5,- ).
Verzonden vanaf mijn Galaxy
-------- Oorspronkelijk bericht --------
Okay. I was wondering: with H plates I can drive into these zones, but seems as if you (and other guests with older vehicles) can’t. So you’re completely forbidden do go into there.
At least it’s clear - we had a long telephone fight with London and their LEZ/ULEZ theatre and they didn’t know what to do: My XJ wasn’t on their list. They wanted us to pay. Then, they sent us a very friendly letter 6 days after a written inquiry, allowing us to enter (which wasn’t what the website or the one on the phone said)… but one has to be careful not to enter the inner circle as they have cameras everywhere for the exact purpose of ripping you off.
I‘d rather risk paying a fine if I had a ‚banned‘ vehicle than buying a new car if it’s just once or twice a year. I‘m not harming anyone and sometimes it’s unavoidable. They‘ll only see it when writing parking tickets etc. as far as I know. Lucky you that your V12 qualifies! Thanks for the answer.
Even in Germany, not every car of a certain age automatically qualifies for H-plates (or oldtimer plates for the people not well versed in European / German license plates).
The car has to look the part too. If the “TüV” technician doesn’t like the state of the car, no oldtimer privileges…
The green “Feinstaubplakette” can be obtained quite easily. Just snail mail a copy of the vehicle papers that proove the car has the right age, together with a 5 euro bill, to a specific address in the city of Cologne and you’ll receive the sticker by return snail mail…
If someone is quite knowledgeable with e.g. photoshop, he could order an official green sticker with the accompanying letter of authenticity and would receive it. Nothing except production year is checked…
Same with the CritAir certificate in France…don’t ask me how I know… 
1 Like