- Went to Tyres Northampton today about my failed MOT on emissions.

- Found out my centre cat is knackered. Borrowing a friend's from a UK spec to get through MOT on Saturday.

Questions:

1 - T.N. do a straight through Scorpion centre section - either fit this or refit the knackered centre CAT. Will the Decat make any performance difference? Any danger putting the knackered CAT back on?(D/P still has CAT). Advice please.

2 - What should I do about future MOTs - borrow my generous friend's centre CAT or try and source a new/used centre CAT for future from somewhere? Any ideas?

3 - What do I/should I tell the insurance re: the decat section if I get it?

Quick ideas please - going back on Saturday!

Thanks Rikki

 

Come on guys - I need to know by Sat morning

 

I don't know wether it would work or not, but you could always beat the cat in the centre section until it breaks up and come out of the pipe ihn bits, that way it would look right, but not have the restriction!
Like i said it might just be a crap idea.
But then again, who know's!
Ron

 

I wouldnt suggest using the original cat if its damaged, you may find the material inside the cat will come out and may cause problems further down the system. Also if the cat breaking up, chances are that its affecting the gas flow.
Personally i would go for the scorpion centre pipe, which will fit to your exsisting front pipe (retaining downpipe cat) and join onto the rear box. It will also be alot cheaper than buying a new cat!

 

A suggestion had been made about using a broom handle to get the cr*p out of the existing broken CAT and putting that back on. I guess it is probably best to get the replacement pipe.

What about when I sell the car though - I will need a CAT or something that looks like it then?

 

Rikki

I had a Magnex backbox and decat centre fitted in January and the result of both is awesome. The sound, as with all non-standard scooby boxes is wicked but the most noticeable difference, and I'm sure this is down to the removal of cat only, is that the turbo starts to spool up at least 500 rpm sooner and it pulls much much stronger through the middle revs.

Get the decat centre from TN - had mine fitted there. When I need my MOT done I will use a garage I know (near Nothampton ) where they can put on a temporary section to ensure emissions are ok.

Tell the insurance - I was with Eagle star and despite them not liking mods it made no difference. Normally they allow less than 10% performance gains from exhaust mods which would mean 20bhp on my UK95 - I would guess that the decat centre gives no more than 8 - 10 bhp (decat downpipe apparently alot more).

Cheers
Paul

[This message has been edited by Kempo (edited 12 October 2001).]

 

Thanks a lot Paul.

What is this temporary section? Surely it must be the same thing as taking the decat pipe off and putting the cat back on for the MOT then swopping again after?

I am guessing that I won't see much performance increase from putting the decat centre section on because if my CAT has 'collapsed' anyway then a lot of the restriction will have already been removed?? Anyone care to comment?

Paul what did you say to the insurance company? I have beeen recommended to say that I am having a full stainless exhaust fitted rather than saying I am having a Scorpion Cat replacement pipe fitted.

Thanks Rikki

 

Rikki
I basically disclosed it to the Insurance co. as a non-standard exhaust. I said I have a stainless steel exhaust, they asked if it was performance enhancing and I said "I think so ", they asked is the increase less than 10% and I said yes, which is true.

I'm not sure about you're cat and the state it is in but my intuition would be that if a cat is a restiction and it is dmaged then it is a restriction that is not functioning efficiently - I would imagine it was worse than a normal cat??? Taking it off or replacing can only be better...

Yes, the solution I meant involves replacing the normal cat section for a temporary purpose then putting yours back on.

Paul

 

I had trouble with an insurance company which didn't like the fact that the car had been totally decatted even though it's an import and I don't think it needs them.

Follow the recommendation and tell them you have a stainless steel pipe on the car, you aren't lying!

P.S. The garage where I got my exhaust done said that I'd probably only need to refit the downpipe cat to pass the emissions of the MOT. Go on do it, you know you want to!!!

[This message has been edited by ZAZ (edited 12 October 2001).]

 

Hi.

ditch the cat pipe. Braking off wont matter, there is only a silencer downstream.

After that, dont worry about insurance or get a scoobysport converted centre pipe which still has a resonator box in which will look like a cat anyway.

The thing is, most of the emissions improvements come from the front cat which gets much hotter and therefore work much better.

I find it strange, that the centre pipe affects things that much emissions wise.

Other option is to find a garage for your mot.

either way ditch the cat. Performance should increase. I would ditch the downpipe cat too.

 

Hi.

ditch the cat pipe. Braking off wont matter, there is only a silencer downstream.

After that, dont worry about insurance or get a scoobysport converted centre pipe which still has a resonator box in which will look like a cat anyway.

The thing is, most of the emissions improvements come from the front cat which gets much hotter and therefore work much better.

I find it strange, that the centre pipe affects things that much emissions wise.

Other option is to find a garage for your mot.

either way ditch the cat. Performance should increase. I would ditch the downpipe cat too.

 

Off to Tyres Northampton now.

Going to get the centre cat removed.

After searching on "Scorpion" in Drivetrain I am well tempted to go for the downpipe as well but my money is a little tight, plus it willl need swopping again at MOT, so I think I'll just stick with the centre pipe for now.

BTW, mine wouldn't pass emissions with just the front CAT!

 

Paul,

Interesting remarks with regard eaglestar, I called them about a back box change and they refused point blank - told them stainless exhaust definitely less than 10% performance increase. No Joy at all.

When did you call them was it last year.

T.