forum.audiv8.com Foren English Audi V8 Forum cats

Are the 3.6 and 4.2 pt and abh catalytic convertors the same , my abh cats[ 1994] are now loose in their housing and i am going to de cat the pt [1990], so where do i get decat pipes and who has a good pair of abh cats for sale??

They look the same, but I think the ABH pipes have a different bore- larger. The pipes are also different lengths.

My car is running a hybrid exhaust. ABH rear section after the cat pipes. PT cat pipes and crossover pipe. The PT cat pipes are shorter by several inches.

I simple broke up the CAT coreson mine, and left the boxes in place.

De-cat pipes are probably best getting made by any decent exhaust company, but there are a few concerns.
- don't let them make any mods to the crossover pipe. I've seen several nasty by-pass efforts where the cross over pipes we're cut, making future serviceability difficult.
- if you must, get bypass pipes made with mounting flanges. The flanges from the existing cats would do.

As a starting point, why not do as I did, and empty the cat boxes on both cars, and leave them in place. Test the emissions, and see how you go. You might be pleasantly surprised, and it may be much cheaper.

i will try that first, did you cut and reweld the cans or did you manage to get the internals out with a drift?

I was able to employ a very subtle technique with long metal implement via a most convenient orifice.
The phrase 'they don't like it up 'em' springs to mind.

It took longer getting the cats off than it did emptying them.

good news, in the words of jean luc picard[cptn starship enterprise]
make it so,,
thanks for the info mark,
how is your fleet getting on ?

I'm in the process of planning musical chairs with engines.

The engine in the silver v8 is now burning oil too heavily. However, it works fine otherwise. I'm swapping in a new engine shortly.

Then, I have to try and diagnose the damage to the lago car that roger Galvin kindly screwed up for me. If the engine is toast, then I'll swap in the smoking v8 to get it going again.

Whatever spare engine I have will be used to build/adapt engine mounts to make swapping in an ABZ easy, and to start the manual transmission conversion for one of the cars, along with the throttle body conversion.

Just a few projects for the winter.

busy boy, did the cats at the weekend , feels crisper and better fuel economy?, just got to sort the valve stem seals now, the joys,,,