GS back boxes on 4200?

Delmonte

Member
Messages
235
Considering these for mine. Whats the deal with this? I assume they fit no problem. So do you get the throttle valve noise thing if you fit them? Or is there other bits you have to buy to get that?
And assuming it all works, what's the noise difference like compared to the stock 4200?
 

CatmanV2

Member
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30,855
Will fit fine, but you need some kind of control kit otherwise your valves will be open at all times.This may not be a bad thing

C
 

FIFTY

Member
Messages
1,801
Considering these for mine. Whats the deal with this? I assume they fit no problem. So do you get the throttle valve noise thing if you fit them? Or is there other bits you have to buy to get that?
And assuming it all works, what's the noise difference like compared to the stock 4200?

  1. The deal is they are great
  2. No fitment problems if anything easieras the stock 4200 boxes are massive in conparison to the GS ones
  3. No. Upon fitment the boxes will have the valves stuck upon. In order to manually operate the valves with a key fob controller you need to run a vacuum line from the engine to the boxes and then a EGR valve with controller to operate the vacuum solonoid to open/close the valves. The kit you describe which taps into the throttle does exist... Larini make it costs £400. The manual egr with fob which I have is about £50
  4. As mentioned above either nothing of youe want to leave the valves open or a manual valve kit or the throttle controlled valve kit from Larini
  5. They sound great... Little more high pitched and raspy than the stock 4200 boxes. They sound much better on the over run... bit more crackle
 

Delmonte

Member
Messages
235
Thanks for the thorough reply @50. Though if I need another £400 piece of kit to make them 'work' I probably won't bother because the ones I've seen aren't cheap in the first place. Good knowledge
 

rockits

Member
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6,448
I think to buy new 4200 larinis is about 1300 then 1700 for the valved ones and another 400 for the remote kit.
 

FIFTY

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1,801
Thanks for the thorough reply @50. Though if I need another £400 piece of kit to make them 'work' I probably won't bother because the ones I've seen aren't cheap in the first place. Good knowledge
Well that depends on what your view is... The OEM set up on the GS is that when the valves are closed (not in sport) over 4500 RPM the valves open. This is what the expensive Larini kit mimics: https://www.larinisystems.com/collection/maserati/4200/larini-auto-valve-control-remote-exhaust-kits

You can get everything in the kit minus whatever device Larini offer to tap into the throttle for less than £50 from China. This is what I bought, the only thing to note is that the hose they supply is far too short so you can buy more off amazon for a few pounds per metre. https://www.ebay.co.uk/itm/New-Control-Exhaust-Valve-Cutout-Wireless-Remote-Controller-Switch/172931946254?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

I don't think I am missing anything by not having the switch set to 4500 RPM, if anything I can be more discreet without the car suddenly jumping 20db if I rev it out a little bit in town.
 

CatmanV2

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30,855
It's an interesting one. Having the valves fully open at all revs makes take off rather louder than the engineers intended.

C
 

safrane

Member
Messages
12,167
Was not Benny's contact stripping out standatd 4200 sets and fettling them to be the same as the GS at far less cost than the GS ones????
 

Delmonte

Member
Messages
235
Well that depends on what your view is... The OEM set up on the GS is that when the valves are closed (not in sport) over 4500 RPM the valves open. This is what the expensive Larini kit mimics: https://www.larinisystems.com/collection/maserati/4200/larini-auto-valve-control-remote-exhaust-kits

You can get everything in the kit minus whatever device Larini offer to tap into the throttle for less than £50 from China. This is what I bought, the only thing to note is that the hose they supply is far too short so you can buy more off amazon for a few pounds per metre. https://www.ebay.co.uk/itm/New-Control-Exhaust-Valve-Cutout-Wireless-Remote-Controller-Switch/172931946254?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

I don't think I am missing anything by not having the switch set to 4500 RPM, if anything I can be more discreet without the car suddenly jumping 20db if I rev it out a little bit in town.
OK, I get you. But, how does GS loudness (valves open) compare to 4200? And for that matter, with valves closed? Quieter? Does std 4200 sit between the 2 modes or is it quieter than both?
 

CatmanV2

Member
Messages
30,855
I don't think there's a whole load of difference between the stock 4200 and the GS with valves closed. It might be a bit quieter due to the different rear box design.
The GS with the valves open will be quite a lot more assertive, but again the 4200 with valved boxes is going to sound pretty much identical.

C
 

zagatoes30

Centenary Club
Messages
13,047
Pretty sure my Spyder had modified GS boxes, Matt will confirm. It didn't have any fancy valves though but had a lovely balance of sound (IMO), not too shouty just enough to make the hairs on the back of your neck stand up
 

CatmanV2

Member
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30,855
GS boxes come with valves. Unless someone cut them out, which is certainly possible but slightly perverse.

C