Engine conversion options

 I'm right at the earliest stage of planning this swap into my '86 300GD and have been talking with a few people here and elsewhere (Pointed 3, Superturbodiesel are good sources) who have been through it.

A recent thread on this was here http://www.gwoa.co.uk/forum/axel-burg-606962-g-conversion 

The one thing I have learned is that it isn't a trivial Sat PM job.. or at least it isn't if you want to do it to a high standard.

There are a few people who will do it on a commercial basis for you too, which might be a good route if you don't fancy the grief (G class centre is one name that comes up time and again).

So far, I've bought a complete low milelage '98 engine and 603 mechanical pump (into which the 606 plungers need to be swapped). I'm planning to hook that up to a 711.620 5 speed manual transmission from a Sprinter van with a solid flywheel conversion.

I'm now just working carefully through the complete list of parts and changes I think will need to be made before getting started.  I plan to document every step as I go though (including part numbers so that might be useful to you) and I'll post it online somewhere.

The questions I think can answer (though others will correct me as neccessary please - I  am learning here myself as I go) are:

1. With the 606 plungers fitter to the 603 and some adjustment, you could expect standard 606 T (174hp/ 300Nm or so at the crank) - perhaps a bit more.  If you go bigger turbo (Holset HX35, 40 or similar) and a fettled pump (Myna in Finland seem to be a favorite), then anything upto 400HP seems fairly common with stock internals. Don't like Turbo lag? add an Eaton M90 supercharger (not sure where it would fit!) and get + 40% across most of the range. Start changing stock Internals (rods etc) and north of 600HP is in the realms of possibility it seems. The 606 is hugely flexible and evidently very strong.

I'm shooting for the standard turbo performance which with the gearing I have (35" tyres standard 4.88 final ratio) will put me at around 2600 RPM at a sensible cruising speed (anything over 3K it drinks petrol I'm told).

2. No - you'll need a gearbox that has a suitable flange to suit the 606. I haven't done a lot of research here, but it seems many of the modern Merc boxes do. Axel-Burg's conversion is using a 6 speed CLK box I understand.  You need something that will handle 300 Nm and in answer to 3) most likely if it is the ususal Getrag that was fitted to the 300GD.

You will also need to consider the output shaft flange.. again more research I need to do here.

Some of the other major concerns I've learned about are:

Diff clearance.  Unless you fancy either:

i) cutting and re-welding the sump from a 606 saloon or
ii) making custom frame mounts (+50-75mm I think ) which I'm not convinced are great

then you'll need to buy the correct 606.964 sump (fitted to the 300 Turbodiesel G) which is c. £800 or so (I'm still trying to confirm the precise # number for it as there are 2 or 3 variations shown on the EPC diagram - anyone know which is right?).

It might be that you still need a body lift tp clear the transmission in the tunnel (again this is not immediately clear from other people experience).

I was also advised yesterday that clutch setup can be a real bitch too. Not sure if that is specific to one combination of flywheel and trans or just generally.. since there's no Workshop manual for this mostly you have to find out the hard way it seems!

I know that there are a ton of other potential problems too (waterpump, throttle setup, brake booster).. hell I should be talking myself out of it really... On the other hand I've been totally inspired by the antics of those crazy scandawegians who seem to ignore the 'why you shouldn't' arguments and do some inspired things with the 606s.

Cheers

Have a look here:

http://www.clubgwagen.com/forum/viewtopic.php?f=18&t=2913

That ackelaid goes to stig, it wasn't me.  Not sure about the spelling though, even my spell checker doesn't know it.