Hello all.

So we got a new to us RRS V8 AB Overfinch and as I expected, the Mrs says it's too loud for her to use as her daily. So without knowing EXACTLY what Overfinch do to the system to make it louder, how do I go about making in stock again?

I realise I can try to find a full secondhand system on somewhere like eBay, but I think it's a bit of a nightmare to fit? Maybe I'm best looking at having silencers fitted....maybe downpipes?

TIA

Downpipes will not do any difference, it's not a turbo.
I believe Overfinch played with the rear silencers. Regards etc.,

Wojtek

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WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE

What model do you have?

TheWojtek wrote:

Downpipes will not do any difference, it's not a turbo.
I believe Overfinch played with the rear silencers.

Replacing downpipes (which would essentially create a whole new exhaust from the headers back) with high-flow units does not have a big implication soundwise, has some challenges though:
- bigger downpipes are hard to fit into already crammed space
- it would call for reusing the stock cats (economically challenging because removing and attaching them to the new system) or
- it would call for using replacement aftermarket cats (again, expensive)
Since the car needs to stick with emission levels as designed by factory, most tuners work with catback systems - let the OEM stuff deal with the emissions and play free with everything afterwards. The well-known mod to the RRS exhaust is replacing the middle resonator with a less restrictive unit - or binning it altogether and putting a straight pipe instead. The other way of achieving (a slightly different) louder sound is by replacing the rear silencers. My bet is on the latter, however if it was a really expensive exhaust, it might have been a full system - but it seems less probable to me. Regards etc.,

Wojtek

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WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE

Thank you very much for the information Wojtek.

We haven’t managed to have a look underneath, other than a quick check under the back bumper and the rear silencers are definitely still there. Couldn’t see far enough forward, but might Jack it up over the weekend to see what else is going on.

So far it does just seem like a modified stock exhaust from your suggestions.

Whilst the removal of the rear silencer(s) will make it louder, it's the centre box that does the main silencing, the rear boxes mainly affect the tone.

My guess is the centre box has been taken out, or a X pipe has been put in in its place.


Dave 2010 3.6 TDV8 HSE (Gone)
2011 Discovery 4 Commercial SDV6 (Gone)
1980 OBLIC 4.0ltr Range Rover (went a long time ago)

Thanks Dave. Hope to confirm later today.

Dave has a point. From what I've found, the Overfinch exhaust replaces the stock middle resonator with a significantly smaller unit and uses homeopathic amounts of muffling in rear silencers in the L320 and I wouldn't expect the L494 unit to be very different. @drb5 - once you're from below the car, check if yours is similar. Regards etc.,

Wojtek

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WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE

Well, it isn’t quite how I imagined it to be.

The cats have clearly been removed and then poorly welded up. The pipes going into the most forward silencer are also welded poorly, even though there’s clamps right next to the welds…? The system is then all good till after the second silencer when Stevie Wonder has tried welding again.

Two rear silencers look untouched…at least from the underside they do…

Oh God, that is painful.
So possibly they moved the csts downstream for a bit more prerformqnce, gutted 1st silencer and then left it stock…ish? Regards etc.,

Wojtek

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WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE

You got that right!

In a way I'm still happy to see the boxes are still there however. Means I may be able to salvage the setup, by opening it all back up and modifying/fixing what they've done.

Hopefully I remember to take some pictures when I get round to tackling it and fire them up for reference. Just got a few other small job on it to take care of first.

Not sure about Overfinch being responsible for that, looks more like the welding was done by The Backstreet Bodgit Company.

Cheers
Coi

I’d have agreed with you Col, but from what I’ve managed to find out so far, it looks like OF dont this type of job up to maybe 2017/2018 and then they brought out their own system…?

Why not speak to Over Finch and ask for their advice? Tim
RRS sold and replaced with a Skoda Kodiaq after appalling RR Dealer experience and LR inability to supply new cars in any sort of reasonable time frame..