3.5 V8 Efi Exhaust de-cat

Hi,

My exhaust is dropping to pieces so I thought I'd use the oppurtunity to 'remove' the Cats.

I was thinking of replacing the whole system with the 3.5 Efi Non-Cat exhaust system. Two queries... Firstly, is the connection at the manifold the same? Secondly, what do I do with the Lambda sensors?

Emmissions aren't a problem as I'm running on LPG.

Has anyone done this?

Cheers,

Ian

whether emissions are a problem or not, when it comes to mot time, if yer motor was made with a cat on it then it needs to be fitted to pass the mot

Cheers for your reply Yella,

I was under the impression that the MOT test had to simply meet emissions requirements. The removal of a Cat (or two) contravenes the Construction & Use Regs, but to pass the MOT it isn't relevant. I await to be shot down in flames!

When was your disco first registered ? If it was before 1st Jan 1992 you can get away with a pre cat test.Wether or not you keep the cats you need to keep the oxygen sensors in the downpipes - or change the tune resistor or the 14cux engine ecu will be looking for inputs once the engine gets up to temp.If it does not see proper switching of the sensors under certain conditions you will get all sorts of driveability issues - including stalling at junctions etc.Plus you will be lucky to get it through any kind of emissions test.

So if I didn't have the Lambda's do I just unplug them and change the tune resistor, bearing in mind, they do nothing most of the time as it runs on an open loop LPG system.

BTW, where is the tune resistor? Is it the little black 'thingy' connecting to wires together sticking out of the loom near the air flow meter connector.

Cheers.

I had a terrible rattle in one of my cars...and thought the exhaust system was falling apart. It turned out to be the contents of my catalytic converter that had reached its use by date and turned into a clump of something nasty inside the converter. I had the contents removed and kept the shell of the converter so when the rego people looked under and saw it, I was ok! No emission tests over here

The tune resistor is plugged into the loom about 9-12 inches from the main Ecu plug,cant remember the p/n you need,can look it up if you want.
I still cant believe they dont have RWC in Western Oz,it would take 1/2 the vehicles off the road if they had it ! Mind you they dont even have proper speed limits up in the "Territories".
Fantastic place to live !

I shall have a look for that one then. I seem to remember some wires sticking out of the loom when attempting to fix the heater.

Too right about Oz. I spent a year there and drove the whole country. Covered 18,000 km's in 3 months! I agree with the RWC though. Our van was on WA plates so didn't need an RWC but it would have failed spectacularly! On the plus side the hole in the drivers floor allowed easy access to the front wheel for emergency braking purposes!!

Let me know if you see it. It's a yellow (or was till I painted it with palm trees and stuff) Mazda E2000 van Rego: 1AAP 075