Hello everyone,

 

After some advise I'm thinking of buying some high flow cats from z1 motorsports in USA. Has anyone dealt with them before? And can't find shipping cost to the UK never imported parts before is there any chargers?.

 

Luke

Lots of people use them, but they are quite expensive and hit you with shipping and tax that isnt included in the price.

 

Why not just use decats?

I decatted my exhaust last week to stainless for £300 but did keep my stainless exhaust rear boxes.

You can get sports cats in the uk no need to go to usa for them

I will look into the sports cats. Is de cat safe heard A lot of stories of blowing turbo seals don't know how true the stories are though.

Not heard of that & the exhaust specialist suggested going stainless & decatted .

Cheers for replies I will pop into exhaust specialist near me and get some prices....

Looking at performance tests on the interweb the sports cat are a good idea when your old cats are done and your changing them anyway, if not the gains especially on standard motors is small, maybe 10 bhp and some times even worse so a large chunk of cash for nothing really.

 

 

Jeff

Not heard of that & the exhaust specialist suggested going stainless & decatted .

 

Two things to remember if you decat;

1. It could fail the MoT as test stations software has now been updated to include old vehicles and if listed with cats then if removed will fail the test.

2. If you decat and have old turbos they will fail, this is due to the reduction in exhaust back pressure ecentually affecting the turbo seals.

 

Stick with Cats in whatever form.

Two things to remember if you decat;

1. It could fail the MoT as test stations software has now been updated to include old vehicles and if listed with cats then if removed will fail the test.

2. If you decat and have old turbos they will fail, this is due to the reduction in exhaust back pressure ecentually affecting the turbo seals.

 

Stick with Cats in whatever form.

 

Is that quite right?

I thought Z32s pre 93 were regarded as pre cat and not subjected to this?

The turbo seals probably already have failed in this instance and the decat/loss of back pressure simply illuminates the fault.

As Jeff has alluded to, Z32 cats are pretty free-flowing anyway, I wouldn't replace them with 'sports cats'.

Not saying this is gospel, but as I understand things with regards to having catalytic converters fitted, the following was applied during my recent MOT test.

As my Zed was registered between 91 and 95 and the VIN number could not be found on the database at time of testing, the tester proceeded to go through the BET test and then on to a lesser emissions test, ie 3.5% CO, which of course it passed with ease.

Also, although my car was originally fitted with cats at time of registration, due to the above information, it could be tested with or without.

Again, I'm not saying that this is 100% factual, it is just based on my recent test.

Yeah don't think I'm going down the De cat route it's just my exhaust has a very slight blow and was just thinking of going full stainless ,when I bought the car it already had a cat back system so was just thinking shall I finish the rest of the system off....its my first z so unsure of what's best for the old girl.

Is that quite right?

I thought Z32s pre 93 were regarded as pre cat and not subjected to this?

The turbo seals probably already have failed in this instance and the decat/loss of back pressure simply illuminates the fault.

 

My local mot station informed me that their software had been updated to include older vehicles, how old l never enquired as l no longer have a 300zx but the comments were made in relation to my last Zed which was 93L plate model which was decatted and they had mot'd many times previously without problems. I believe the comment was to signify it would not pass now.

My local mot station informed me that their software had been updated to include older vehicles, how old l never enquired as l no longer have a 300zx but the comments were made in relation to my last Zed which was 93L plate model which was decatted and they had mot'd many times previously without problems. I believe the comment was to signify it would not pass now.

 

Interesting, i know nothing was said last year and the guy was a real jobsworth. There used to be differences between U.K. And JDM cars too. Be a right mare if we all have to go reinstalling cats.

Are there any members on here that are mot tester that can let us know as i have a pair of decats an elbows to fit to my zed thanks

Edited July 16, 20178 yr by stephenk

Reply from VOSA when asked to clarify the position, having personally taken hundreds of zeds for MOT testing over the years I can confirm the following seems to be about as accurate as you can get, there is a valid argument to be had when some testers will just do a full cat test if the car is registered after August 1992 without checking the rules ie

 

"If there is not an exact match in the Emissions book, then the vehicle will be subject to a non-cat emissions test "

 

we know and can see from the link / picture below the 300zx Z32 no longer appears on the data sheets, be aware that some testers even confuse the z33 350z and it is highly doubt full the average 300zx will pass that test, worth printing off the section from the VOSA site and taking it with you for MOT if you want to decat or even if you have a post August 93 that is running a bit high on emissions ( not unusual for infrequently used cars ) the text in red really is the key point.

 

 

VOSA

Spark ignition cars first used on or after 1 August 1992 are subject to a Basic Emissions Test (BET) regardless of whether a catalytic converter is fitted or required. In the event that the BET is failed, it becomes necessary to reference both the MOT Inspection Manual, Section 7.3 and the In Service Exhaust Emission Standards for Road Vehicles publication (Emissions book). The MOT Inspection Manual is available on-line at http://www.motinfo.gov.uk/htdocs/ and the Emissions book at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/194133/Emissions_17th_Edition.pdf

 

 

 

For vehicles first used between 1 August 1992 and 31 July 1995, if there is an exact match for the vehicle in the Emissions book, then a full cat test must be carried out. Where this is the case, the vehicle must have a catalytic converter fitted or it will fail, regardless of the result of the emissions test.

 

If there is not an exact match in the Emissions book, then the vehicle will be subject to a non-cat emissions test (two gas test). Where this is the case, the vehicle is not required to have a catalytic converter fitted for MOT purposes, regardless of whether one was originally fitted.

 

Technical Standards Team|

 

Testing Schemes Management

Incorporating the Driving Standards Agency and Vehicle and Operator Services Agency.

http://www.gov.uk/vosa

 

 

Edited July 16, 20178 yr by JeffTT

I rest my case, thanks Jeff. :lol::thumbup1: