Decat on 08 Granturismo

[r3ni00]

Hi all,

I've been looking at getting a larini backbox and after discussing this with a garage that has worked on my car they've surgeusted that I could just decat it instead. Has anyone here had it done and if so what's your thoughts on it?

Also I'm based in the U.K. Is there any implications with getting this done i.e. MOT etc..

Thanks
Jason

 

[GeoffCapes]

Larini back boxes will increase noise.

Most go down the X or H pipe route first (probably as it's much cheaper. Then back boxes then de-cat.

Or do all three like Phil has.

I'm guessing yours is a 4.2 being a 2008? So if you do go for larini back boxes you might want to get valved ones as well.

 

[bigbob]

Surely a decat will fail an MOT?

 

[StuartW]

On my GTS MC Sjhift, I had Larini sports cats (now on Phil's car), Larini X pipe and Larini back boxes. It was insanely loud and frankly ridiculous, I very rarely opened the valves. It was fun on the way home but tiresome after that.

As Mark says, I would suggest the X (or H) first, and then the sports cats OR the back boxes but not both. There will not be an issue with the MOT for sports cats but I did get an advisory for loud exhaust and that was with the valves closed.

 

[CatmanV2]

Hi all,

I've been looking at getting a larini backbox and after discussing this with a garage that has worked on my car they've surgeusted that I could just decat it instead. Has anyone here had it done and if so what's your thoughts on it?

Also I'm based in the U.K. Is there any implications with getting this done i.e. MOT etc..

Thanks
Jason

I'd have thought a de-cat is bound to fail MOT

I have a spare, custom H-pipe looking for a new home. Yours for much cheapness

C

 

[r3ni00]

Thanks guys, maybe I need to reconsider my options on this then.

I've looked at the X-pipe previously but not the H-Pipe.

 

[CatmanV2]

Thanks guys, maybe I need to reconsider my options on this then.

I've looked at the X-pipe previously but not the H-Pipe.

You could add sports cats, but I *think* that's usually regarded as the end of the process.

C

 

[Caldy999]

You could add sports cats, but I *think* that's usually regarded as the end of the process.

C

Hmmm.....not necessarily - are you seeking noise or power/driveability? If you replace the cats first, together with a revised X or H pipe, you get a performance uplift without making the exhaust overly loud. Then if you want a volume increase, simply change the back boxes.

 

[JJbing]

Straight pipes will 100% bring engine management light on!
I’ve ran decats in my previous cars.. not a problem if you don’t mind the light/ have a friendly mot’er. You could try an O2 spacer but it’s really hit and miss if they work

 

[Contigo]

Right you can't decat them as they have 600 cel cats on the downpipes only so removing these will result in CEL / limp mode and you run the risk of high EGT's. You could start at the back first with removing the back boxes and going straight through or 4.7 S back boxes with Valve control. I would start at the back and work forward.

 

[r3ni00]

Right you can't decat them as they have 600 cel cats on the downpipes only so removing these will result in CEL / limp mode and you run the risk of high EGT's. You could start at the back first with removing the back boxes and going straight through or 4.7 S back boxes with Valve control. I would start at the back and work forward.

Hi Phil,

Thanks for the heads up, if the back box is removed could there be any potential issue with the engine management light etc?

 

[CatmanV2]

Hi Phil,

Thanks for the heads up, if the back box is removed could there be any potential issue with the engine management light etc?

Nope

C

 

[r3ni00]

Nope

C

Thanks

 

[CatmanV2]

Thanks

No worries

C

 

[Contigo]

Nope as C answered. The only light you will get is the blue light from the Dibble when you go past them at over 120dB and they are having a quiet day

But in all seriousness the best option is to go with S boxes with valves like C has on his. There are a cheap pair out there now on Ebay IIRC.

 

[CatmanV2]

Nope as C answered. The only light you will get is the blue light from the Dibble when you go past them at over 120dB and they are having a quiet day

But in all seriousness the best option is to go with S boxes with valves like C has on his. There are a cheap pair out there now on Ebay IIRC.

S box? Is this a new exhaust type?

C

 

[StuartW]

Nope as C answered. The only light you will get is the blue light from the Dibble when you go past them at over 120dB and they are having a quiet day

But in all seriousness the best option is to go with S boxes with valves like C has on his. There are a cheap pair out there now on Ebay IIRC.

Thread below which I posted a week ago and it looks like they're still for sale too

http://www.sportsmaserati.com/showthread.php/25034-GTS-Auto-OEM-Valved-Boxes-For-Sale

 

[r3ni00]

Thread below which I posted a week ago and it looks like they're still for sale too

http://www.sportsmaserati.com/showthread.php/25034-GTS-Auto-OEM-Valved-Boxes-For-Sale

Thanks for this, I've just purchased them

 

[CatmanV2]

Thanks for this, I've just purchased them

Jolly good!

C

 

[StuartW]

Thanks for this, I've just purchased them

You're welcome, they were a bargain