I learned an interesting fact yesterday - whilst I knew that early versions of the Bentley Arnage employed the same BMW 4.4 V8 and ZF auto as the early L322, I hadn't realised that the Arnage had a Cosworth twin-turbo setup giving an extra 60bhp and 100lb.ft of torque.

Now, this strikes me as something fun to try in an L322 - 5.0 supercharged performance with better economy and the ability to still run on lpg without valve worries. I wonder, has anyone ever tried transplanting the turbo bits - and if not, how hard can it be? NW060

"Red Shed" - 1982 Series 3 88" County Station Wagon
"Spirit of Great Britain" - Rolls Royce Meteor V12 engine
ZG875 - Westland Sea King (cockpit section)
"Carly Rae Jeepsen" - 2006 Jeep Commander 5.7 Hemi
"Pride Of The Road" - 1/4-scale Marshall traction engine - sold
"Georgina" - 2000 Discovery 2 TD5 ES - sold
"Windsor" - 2005 Range Rover Vogue 4.4 - dead

you would need to find an Arnage being broken up for parts first! trying to buy just the cream, without the pudding it sits on, would be difficult in itself.. and then you would have the wiring loom to dismantle....i would be looking at BMW forums, as those guys in Germany, know their tuning, and no doubt know the components needed to simply 'bolt-on' etc.
anything is possible.
i have researched transplanting modern merc AMG engines into old jag classics, as they are so much better, and getting a whole smashed car is easy. mounting/plumbing it in is DIY. but its always the wiring. coupled with the diagnostics, and the security.
It's no wonder that those Overfinch cars of old, that were re-engined, are now not how Overfinch has become today. they are more 'fancy dress', than 'wolf-in-sheeps clothing'.

It would actually be easier, to pull the heads off an SC 5.0 l322 and re seat the valves in steel, and run it on LPG.

^ the 5.0 is direct injection and almost impossible to LPG. It relies on the flow of fuel through the injectors to keep the injector tips from burning out.

Agree on the underfinch of today though. A far cry from the days of the 570.

As for a turbo on a 4.4, I'd be more inclined to talk to a place like Turbo-Technics about it. Easier, probably cheaper in the long run. Not sure how the 'box would take it though, you might have to get that sorted as well. But, since it's ben done with that engine I'd bet TT know how it's done.

A customer of mine is currently having a 5.0 LPG’d... NOTHING to do with me!!! But was talking to him 10days ago and it was due in the following week for a conversion...

Yeah, I did say "Near" impossible. I know of one which has been done but it maintains 20% petrol and 80% LPG rather than running on LPG alone. That has been problematic since day one and for the cost benefit, i.e. 80 % of your fuel at about half price I really can't see why anyone in their right mind would do it. Problems have been burnt out O2 sensors, failed petrol injectors, presumably because they're now working outside tolerance, and God knows how many attempts to map out flat spots.

Given the cost of conversion, the pay back time, the hassle and all the other malarkey it begs the question "Why?" You can either afford to run it or you can't. I've had LPG cars, several in fact but there really is a time and a place for everything.

Do a search for bow x5 turbo kits .
Don't forget the KIT or you'll get ads for the new x5 turbo

Lots of talk on bmw forums and and it has been done on x5s and 5 series .
Ess and Dinan etc offer supercharger kits too .

mat777 wrote:

5.0 supercharged performance

mat777 wrote:

I hadn't realised that the Arnage had a Cosworth twin-turbo setup giving an extra 60bhp and 100lb.ft of torque.

Bentley have a history of under rating the performance of their cars, no one is going to take their car back and complain that it's producing 40% more power than stated

Those figures that you've quoted is more like the figures that you'd expect from a 1.5 - 2.0 litre engine not a 4.4, and although they operate in different ways a Turbo and a Supercharger produce very similar results when it comes to power gain, so I would suspect that the performance has been under rated.

FYI if Jimmy De Ville can get 570 bhp out of a 5 pot 2.5 litre Volvo engine, I would have thought that a Formula 1 engine builder would achieve more than 60 hp from a 4.4 ltr.  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Remember the torque was pegged in the Green Label to keep the gearbox together.

Much easier (and almost certainly cheaper) to just buy a factory Supercharged.

This would be a cheaper option, and TBH they would appear to be one of the more expensive kits

http://vf-engineering.com/other-bmw/bmw-540740/ Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Boost rises with rpm with a centrifugal supercharger though, not really what you want in a 2 1/2 tonne off-roader. Easier on the gearbox though.

Here you go. Fit this and be done with it.

What's that mzg? A merlin? I do remember a guy back in the eighties built "the Beast" with a 17L spitfire engine. Got into trouble due to having a Rolls front grill. He used to taunt the German Porsche and merc drivers on the autobahn by letting them come astern with lights flashing trying to pass and then blow them away by accelerating to 200mph!

miggit wrote:

mat777 wrote:

I hadn't realised that the Arnage had a Cosworth twin-turbo setup giving an extra 60bhp and 100lb.ft of torque.

Bentley have a history of under rating the performance of their cars, no one is going to take their car back and complain that it's producing 40% more power than stated

Those figures that you've quoted is more like the figures that you'd expect from a 1.5 - 2.0 litre engine not a 4.4, and although they operate in different ways a Turbo and a Supercharger produce very similar results when it comes to power gain, so I would suspect that the performance has been under rated.

FYI if Jimmy De Ville can get 570 bhp out of a 5 pot 2.5 litre Volvo engine, I would have thought that a Formula 1 engine builder would achieve more than 60 hp from a 4.4 ltr.

Dolphinboy wrote:

What's that mzg? A merlin? I do remember a guy back in the eighties built "the Beast" with a 17L spitfire engine. Got into trouble due to having a Rolls front grill. He used to taunt the German Porsche and merc drivers on the autobahn by letting them come astern with lights flashing trying to pass and then blow them away by accelerating to 200mph!