I’m looking for technical help or recommendations on: Exhaust
Someone help me!
My 2001 MX-5 MK2 JC100 just scraped through its emissions again this year and the garage had to hold the exhaust together with paste and hope, so I’m looking for a stainless system.
A number of places have told me that modern cats are no good and I am better keeping hold of the one that is on there (still the original), but I just want to buy a stainless system and not worry about it or emissions again.
Everywhere I look, they seem to offer a de-cat pipe, but the details on road legal systems are quite unclear.
All i want is a stainless, road legal exhaust that will get me through and MOT, dont need any extra performance or noise, but this seems to be impossible.
Can anyone help? What do i need to be looking for? Would a 300 cell sports Cat do the job on emissions? - please help!
I ran for 10 years on my NB with a MX5 parts stainless back box and a mild steel centre section using the original cat and Lambda sensor. It passed the MOT but it needed to get the system really hot. The front half of an exhaust system gets hot enough to avoid corrosion and the original catalytic convertor is very efficient. Steel rear silencers can rot out due to acidic condensation. A new OE lambda sensor should be an advantage. Some MOT examiners do not use the correct settings for a NB
My 23 year old cat is original, when the exhaust started falling apart six years ago I went to Infinitey Exhausts in Dodington just off J18 on the M4 and had them fit a bespoke stainless system with no baffles in the box. Cost 500 squid and still sails through MOT and track noise tests when competing. Used the same company for my previous Passat and Golf, friends have been there with everything from a V8 Rover P6, Merc 280 roadster and even a diesel horse box. If travel is no object to keeping your car in tip top condition I’d definitely recommend.
I had a Milltek stainless ‘cat back’ system fitted by Demon tweaks at least 20 Years ago, (retaining the original cat). 20 years on the car still passes mots and noise checks, and the original cat and lambda sensor are now 32 years old. As a previous reply has said, the front sections as far as the cat get hot enough to dry out every time you drive, so don’t need to be swapped to stainless, and my experience would be a good cat back system will last forever and not damage the cat or affect emissions.