Gransport Decats

[THE BIG DOG]

Could someone point me in the right direction?

[fade2grey]

tada.. http://www.larinisystems.com/catalogue.php

[chillo]

get some made up and remove the horrible squashed part of the link pipe!
The secondary cats are completely unnecessary (and are 600 cell too!) You wont get a CEL light as the lamda sensors are on the primary cats which are on the manifold.
You should gain 30-35bhp!

I have been looking into this and got some good info here at fabspeed who have a couple of videos:
Explanation
http://www.fabspeed.com/videos/Maserati%20Exhaust%...

Demo
http://www.fabspeed.com/videos/Maserati%20Exhaust%...
(keep in mind that the demo has a race back box also so is VERY loud-see at about 3m.45sec!)

A people have claimed that its only US cars which have the extra cats in but that is incorrect!!
Mine has 4 in! Can only think that and the squished section is to keep the power down on the F430 to keep Ferrari happy.


I have found that the best way forward is to keep the standard GS back boxes (made by Tubi anyway) which have the valve in and just replace the secondary cats link pipe and also x-pipe, i'm going to get the pipes custom made and have looked at:


http://www.pdgough.com/
http://www.tonylawexhausts.co.uk
http://www.mijperformance.com/

Let us know ho you get on and if found any other places to custom makes the pipework.
Also have a search on www.maseratiforum.co.uk
there is stuff on there which you will find very helpful!

Edited by chillo on Tuesday 23 June 10:43

[bertie]

Out of interest, what's the benefit of removing the cats apart from noise?

I thought it had been fairly well proved there was next to no performance gain?

Maybe that's not true in the case of Turbo cars like the 3200??

There is no car easier to work on the exhaust than the Caterham and even on that it's a right PITA to have to put them back on every year for the MOT, can't imagine it's be easy on a Maserati

Edited by bertie on Tuesday 23 June 11:04

[chillo]

the main gain is from removing the squished part of the link pipe which goes under the steering rack etc You do have to be careful with regards to ground clearance but as you can see here:

It is not a free flowing design!!!
That aftermarket one is a Bertocchi sport cat version IIRC

The standard secondary cats serve no purpose as there is no sensors to monitor if they are working properly or not! and at 600cell they are quite restrictive!! So why even bother the extra expense of a sport cat!
also they get very hot and sit right under the front seats.
Now i know the F430 block is VERY similar but runs 1mm longer stroke/different crank design etc but you can't have a gransport putting out nearly the same power as the F430 can you? (sorry just the conspiracy theorist in me)

Edited by chillo on Tuesday 23 June 12:43

[Burba]

[quote=chillo]...some good stuff and a pretty picture....
Now i know the F430 block is VERY similar but runs 1mm longer stroke/different crank design etc but you can't have a gransport putting out nearly the same power as the F430 can you? (sorry just the conspiracy theorist in me)
[quote]

Agree with you 100% but with re:430, I would have thought there was a little more to it!

[sjn2004]

Out of interest, when the car is up on the ramp, can you see the squished part or is it hidden from view? Seems pretty extreme. The QP has a very restrictive x-pipe,l but thats pretty easy to change, just wondering if it has the same exhaust layout as the GS as the engines are essentially identical.