Catalytic convertors - what to do when they're not available

Someone on the Alfa 75 list has a very late 75 V6, registered Dec. 1992.

Unfortunately, this means it's one of a small handful left that were registered post-catalyst emissions tests.

They currently are urgently in need of a new cat., but Alfa can't supply one and none of the pattern manufacturers make a pattern part.

Would a possible solution be to source a cat. from a car of roughly the same engine size / configuration, chop the cat. out of the pipe and weld on the stubs of the old one?

I'm kind of thinking something from a 3lt Omega / BMW 325i.

Any advice will be passed on to them,

Cheers,

Reply to
SteveH
Loading thread data ...

hi steve. i dont think it will make any differance as long (as you have said) roughly the same engine size / configuration, they all are made the same way just differant sizes and shapes plus fittings.

just check if there is a sensor in the new/old cat. if so make sure yours fits.

Reply to
banjo

Yep.

Physical fit's the critical bit, 1/2 an hour down the breakers yard might the best answer, they keep them.

Reply to
Duncan Wood

Good stuff. That's pretty much what I've suggested.

I kind of figured that you'd also want something built to ensure proper flow of gases from a 3lt 6-pot, though.

Reply to
SteveH

Any standard 3 way cat from a car with an engine of similar hp output (cubic size is irrelevant really) to the Alfa, cropped and re-welded to fit etc will work just fine.

Tim..

Reply to
Tim..

Check the date of manufacture. If the vehicle was manufactured at least

6 months before its date of first use then the date of manufacture is used for test requirements. If that's the case it should be tested to non cat limits regardless of whether or not a cat is fitted.
Reply to
redwood

Does the Alfa have twin exhausts? The Omega has an exhaust for each bank of three cylinders and has two cats, each one for 1.5 litres. The exhausts join at the back box.

Reply to
rp

Good point. I've not really looked at the V6 exhaust system personally.

Looking at the diagrams, I'm pretty sure it's a single cat system - which means an Omega is out of the question.

Reply to
SteveH

SteveH ( snipped-for-privacy@italiancar.co.uk) gurgled happily, sounding much like they were saying :

The system on my 75 2.5 v6 auto was definitely twin pipes all the way back to the back box.

Reply to
Adrian

If you do infact need one then how about one (or two) of the universal cat boxes??

Reply to
adder1969

Universal high-flow cats from ebay are only £50-60 from the states, plenty of car builders using them to good effect...

Reply to
Tony Bond

Thanks all, will pass on the information.

Reply to
SteveH

Try talking to B&M Tyres & exhausts in Mansfield. They have their own manfacturing facility and have supplied a cat for one of my cars that I had been told was main dealer only.

Reply to
Asahartz

Personally I wouldnt bother, unless the car would struggle to make the emissions levels. I know lots of >92 cars who run "sans cat" and still pass MOT without a prob. They are Jap and pretty good emissions-wise to start with though.

J
Reply to
Coyoteboy

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.