Plans plans plans.....

Hi Ian, I don't know who gave you the quote of £1200 for a twin turbo system supplied and fitted but this seems very very cheap.

I am about to have my own '93 300 GEL rebuilt/restored and have some fairly detailed quotes for a single turbo system which amounts to £4200 plus the VAT. This involves the fitting of lower compression pistons, fabricating a larger bore manifold and exhaust and fitting new electronic fuel injection and intercooler.

Running at 1.1bar of boost would equate to around 360bhp which should be enough for what I need. I am told that without the above modifications they could not guarantee a reliable and durable conversion.

I had wanted to go down the route of fitting a larger engine but was persuaded that the turbo route would be just as effective and a lot simpler.

there was an article in the Merc Enthusiast magazine from a couple of years back on the Turbo Technics conversion in a w124 estate, can't find it at the moment. Or if you have lots of cash and patience and a risk taker, you could buy a Brabus large valve cylinder head from a Calafornian seller

"Brabus Cylinder Head for 103 Engine, big valve ported & polished with red Brabus valve cover, all new, $2500.
Bud Insalata; 310-973-5275
Los Angeles
Posted: 2010-03-09"

this is advertised on the
http://www.clubgwagen.com/classifieds/partads.php
website, its still advertised so maybe haggle room. :)

The Turbo Technics kit fitted ran out at something like £7,000 when they 1st came out. But the complete kits were sold off at £1,000 each by a Merc main dealer "Hughes of Beaconsfield?" a few years back. The reason being they no longer have the expertise to fit them. I managed to get one of these kits for the 103 engine and Alan Jeffery of info@enginetuner.co.uk based in Plymouth is recommended to fit them, he quoted me £800-£1000 depending on the need for the compression ratio to be lowered. Not sure about 360bhp though I would be happy with 300 but the brakes are simply not up to this amount of power. And my manual gearbox may not be up to it either. :?

Mercedes Enthusiast issue 91 May 2009, features the w124 with the twin turbo convesion, 500E power and more torque. :wink:

If you want the easy life just buy a 500. It will give you everything you want. Write out one cheque and it's done.

Hi, do you still have the turbo kit and can you tell me what it consists of ?

Hello, no pm recieved as yet.

You should not really need to open the engine to fit low compression pistons now a days.. a decent ECU with electronic boost control, MAP sensor and knock sensor would allow you to run to limit of knock.

Low compression will increase fuel comsumption approx 10% per point.. and knock out the low end torque. Intelligent ECUs allow modern turbos to keep the 9.5:1 compression ratio yet run 1 bar/14 psi boost. Plus if you do this properly you will increase the fuel economy as you can run leaner when off boost .. which can be worth an easy 2 mpg on a standard engine.

A 3 litre could run fine on a single turbo.. it has the bottom end torque if you leave the compression ratio and then it becomes a fill the mid/upper range tool.

Gearbox is the real issue here.. and the old transfer gearbox is torque limited too for power... suspect much over 300 hp will take the transfer box.. and any manual box will be toast at 150-175hp unless changed to a Granny box...

this is on Pistonheads, its a w124 coupe with a twin turbo conversion

http://www.pistonheads.com/SALES/1657931.htm

There wasn't. Both the M104-in-line-6-powered G320 and the M112-V6-powered G320 were exclusively automatics.

But there was a W124 E300 24v with 218 HP and a dog-leg 5-speed manual.

In any event, the problem is about torque, not power.

The standard auto box on the 463s is rated at 280 Nm max torque. Manual is 270Nm.
M103 is rated at 240Nm. So with careful control on the boost to limit the torque you could get away with the standard box.
A v8 produces over 400Nm so you will not get the standard box to last

Turbo Technics claim a figure of 310bhp and 360ft/lbs for their twin turbo kit fitted to a M103.

360ft/lbs is 485Nm of torque which is way in excess of MBs rated figure of 280Nm for the 463 auto box. As has been mentioned earlier the limiting factor might be the amount of torque the transfer box can cope with rather than the gearbox.

Quite a bit of information about turbo charging the M103 engine on the MB tuning sites but can't find anything relating to the 463 or gearbox issues.

As you suggest prwales maybe there is'nt an issue with the gearbox but it would be interesting to know if any modifications were required and also wether the transfer box can handle the extra torque.

so the best advice would be to go either low boost or buy the Brabus cylinder-head from California. Low boost, something around 250 bhp, given I have a swb, would be enough for me :roll:

thanks Roly :lol:

Gearbox is specific to the G as it has breathers and other bits. People have put in boxes from the 126 V8 but that results in more custom work to accomodate it.