Fitting A Modern Engine & Gearbox

[DavidBrough]

As I've been waiting to get my body shell back from the paint shop for some considerable time now I've had plenty of opportunity to ponder what exactly I'll do to it when I eventually start putting it back together. One idea that has started to gain more credibility is the notion that I might actually change the engine and gearbox for more modern MB units but there seems to be so many variants it all gets very confusing and I'm not really that clued up on MB models over the last 6 or 7 years and I wondered if anyone had any suggestions.

At the day of the day my ideal would be a petrol 6 cylinder of 2.5 to 3.2 litres, as modern as possible, with around 200bhp but really no more than 250 with an auto box cruise and A/C. When I Google C-Class there seems to be so many different variants badged as 250/280/300 as W203/204 that appear to fit the bill but I’m not sure which might be the one to aim for. At the end of the day if I do this I may well be constrained by what particular models had a nasty rear end shunt on the motorway last week but would like to try and settle on an ideal so I can see what the costs and effort might be.

[mdsalemi]

David,

Have you taken a good look at the MSL by Mechatronik?  I don't know the details but I believe it was an engine from an SLK.  You can probably contact them, maybe even hop across the channel to go have a look.  Best to make some upfront investment in time and research before diving in.

I believe what they did with the MSL is make it quite a bit different, but they might be able to chat with you about it.

http://www.mechatronik.de/en/engineering/the-m-sl.html

[DavidBrough]

Hi Michael,

It was the MSL that really started me thinking about doing it in the first place and going over to see them is not a bad idea as that should certainly give me a lead on what will/won't fit and the degree of modification necessary. From what I've found out so far the M272 seems to be a good bet in 2.5 or 3.0 form which went into C, E, CLC, CLS, CLK, SLK, R & S models (according to Wiki anyway) so there should be plenty of choice. That said I may have to buy a complete car in order to obtain all the parts needed.

David

[stickandrudderman]

One of the best engines MB ever made was the 3.0 103 engine fitted to most models in the late 80s and for simplicity's sake that would be the engine I would fit if funds are limited. You can buy a whole car for £500!
A member here from Australia has done it so do a search and look it up.
The mechatronix route is a very expensive one and personally I don't see the advantage of having all that electronic control for a (presumably) low mileage car.
If you're looking for someone in the UK to do it for you I'd be happy to oblige.

[DavidBrough]

Hi Stick,

Yes, that does make a lot of sense although I wouldn't go to Mechatronik to do the job as they are far too rich for me but I have asked them if they sell any of the parts that make one fit. I always envisaged the job being done via a donor car and just transferring everything necessary as the fabrication jobs for the mountings, exhaust and drive shaft are basically the same whatever you put in (within reason that is). If I go with this the first requirement is that there is no need to modify any bodywork to make the thing fit. That said, current engines are extremely complicated and I must admit to very little knowledge regarding the electronics and set up requirements for these units and the simplistic premise that a working system, wiring, electronics and all is simply transplanted into a different body may not actually end up being that easy, in the words of Mr Clarkson, “how hard can it be”, very I suspect.

At the end of the day, the only thing about my car I really have a downer on is the automatic gearbox, the engine could be a bit smoother, a little less fickle and more fuel efficient but I can live with that. It's the gearbox that gets me every time (although for me I still prefer it to a manual) and if I could just change that for a modern auto unit I would probably be quite happy especially now I have a 3.47 axle. Having said that, I really like the idea of having a very modern setup in a Pagoda body and whilst not exactly using it every day being quite close. Cost and effort will decide in the end.

Have you undertaken engine transplants before?

[JamesL]

+1 on the  M103. It started, I think, in the 2.6 190E and was a 2.8 in the C (202) and E (124) and I think went up to 3.2 in the 124 and W140. It's a stratight 6 (mine's a c280 from 1995 - other Cs about that time ended up with a V6)

Great engine - once the engine side wiring harness issues are solved. Mine ticks along at 32mpg very happily come rain or shine and will sit all day at 3500 revs illegally and very quietly. Take it abouve 3500 revs and it takes off.

[stickandrudderman]

Tosh, you're confusing an M103 with M104. The latter is an evolution of the former but the former is absolutely the most reliable engine you could wish for if not the most powerful of all the incarnations. Some early 104s were also simple and powerful but are harder to come by whilst all of the 104 after the first couple of years of production came with the fragile wiring loom and expensive and fragile ECU.

David, I've changed hundreds of engines, not always like for like, and not always in cars either! (Bikes, boats and planes too!) but I confess to not having done a swap in a 113 before, although I don't anticipate it being particularly difficult. The hardest part, and as far as I can tell the most overlooked, is re-calculating and then sourcing the correct road spring rates to compensate for the change in weight and even that shouldn't present any difficulty once committed.

[JamesL]

But I do confused so very copnvincingly!

You're right of course. My 202 C280 has a 104. With a replaced engine side harness (the sleeving on the original made from..... biodegradeable material!)

[Sirasila]

I saw in a previous posting by a member called Red Pagoda that he did an engine replacement for his 250SL
Looks to be successful
here's his link
http://www.flickr.com/photos/slpagoda/sets/72157611936779359/show/

[GGR]

Have you considered a Mercedes V8? I believe V8s do a better job with an auto transmission than the L6s, because they have more torque and it is lower in the rpm range. The M117 5.0 and 5.6  and the M116 3.8 and 4.2 are mated to a 4 speed auto, two generations newer than the one on your Pagoda. The M117 is a tight fit, but offers a bigger displacement. It's weight is similar to the M130 thanks to its alloy block.  The M116 is a bit smaller, and a bit lighter. If you don't want any electronics you can fit them with the early K-jet system. The best would be an early 5.0 M117, as it has no electronics. I've seen one fitted in a Pagoda and I fitted one in a W111 Coupe that shares the same chassis with the Pagoda. So I can tip you on what parts to use to clear everything i you want to go that way.

[DavidBrough]

I must admit to not having considered anything much over 3.0ltr as they tend to get a bit thirsty and I do prefer smaller engines generally and am not sure that a V8 burble in a Pagoda would sound right for me. Also the larger more modern units tend to be quite a bit more powerful and I'm not sure I also want the additional mods to cope with that. From what I have now read on the M103 units, that does sound a very good option.

[mirkwood]

There isn't much difference in fuel consumption between the Euro delivered m103 and the m117 that GGR suggests. I note that some say they are reliable...hmmm ,not in my experience. An M103 has an unhappy reputation for head gasket failure and the distributor leaking and/or filling with oil.Plus,in Engine terms,the M103 is getting OLD..
myself,I consider the M130 to be a good engine,only it's combustion chamber is a bit old fashioned and not really conducive to good flow.

 If I were in the  UK I would be seriously hunting for a late model V6 powered C series.
John Olsen has fitted one to a  W111 Coupe and the results are amazing. Far better handling should be achievable ,the reliability of a later,lighter engine with less miles and better fuel economy .The latter being so important in these days of unscrupulous fuel pricing policies.
The trans for the M103 is a regular mercedes 722.xx series which can be swapped for a manual if you know anyone who has parted out W123's ,especially the W123 five speed as found in 240D's. Actually,there was one on ebay.uk just last week with a very low starting price. 

A lot of folks worry(unduly) about the later model cars electrics. A lot of this can be elinated with the use of an aftermarket fuel delivery system such as the Emerald ECu http://www.emeraldm3d.com/
later automatics are electronic without the valve body which is OK for mass production methods to build cars but not so good for us who swap things around. This could be elminated by adapting a manual trans to the rear of a V6 and a bit of digging around could uncover some good trannys in the UK,e.g the landrover fivespeed and Ford untis.

[DavidBrough]

Does anyone know what the main electronic issues would be with say a 1 to 5 year old engine and auto gearbox set up that was lifted lock stock and electronic control barrel from a salvage donor car and bolted into a pagoda. I think the current crop of 2.5ltr V6’s are around 200bhp which would be just fine as I really wouldn’t want much more than that.

[mirkwood]

Send a message to John Olsen. he has done this already 

[Ulf]

Aren't there any regulations on this in your countries? Over here, you can't increase power much before the vehicle needs a new roadworthiness certificate from the authorities. Besides this, you can be ordered to pay more taxes on your car and most classic car insurance companies won't touch anything that's not at least close to original specs. Not to put you off, but have you checked this as it would be a bit of a bummer to do an expensive conversion only to find out that it is not road legal... :-(

Best

Ulf

[mdsalemi]

Ulf, of course we have regulations here!  See all the nonsense about headlights, bumper over riders and such over the years?

That being said, we also have freedom.  Most states have no idea of engine transplants.  Hagerty, a leading insurer here for vintage cars, has a class for modification on their insurance including re-bodied and re-motored cars.

At PUB, one of Joe's neighbors is building his own [AC/Shelby] Cobra 289, from scratch.  There is a class in Ohio for registration of that vehicle, and I'm sure he will be able to get insurance for it as well as a home-built, with proper appraisal and detail.

[GGR]

For people who like to tinker with their cars, the US is just paradise compared to Europe (I know what I'm talking about). On top of that older MBs are cheaper, plenty, same for used parts and new parts can also be had for much cheaper. Make your money in Europe, buy your older MBs and parts in the US. 

[Ulf]

Michael, I know you have regulations in the US, that's why I asked the question in the first place...
And it certainly wasn't meant in a derogatory way - I've just heard so many stories about people spending a lot of money on various modifications only to find out that they couldn't drive their cars afterwards :-)

Ulf

[mdsalemi]

I've just heard so many stories about people spending a lot of money on various modifications only to find out that they couldn't drive their cars afterwards :-)

Not in the USA...unless something really bizarre was done.  Engine transplant should not be an issue, in any state.

[GGR]

I've just heard so many stories about people spending a lot of money on various modifications only to find out that they couldn't drive their cars afterwards :-)

That is true in Europe. Each country has its own set of rules, and they are quite restrictive. In France, they won't consider anything until you provide a document from the manufacturer that supports your modification. This will never happen for a private individual. In Germany, though the TUV is quite restricitive, I hear there are ways to get some modifications accepted. In the UK, up to not too long ago, one could drive anything from a tub or a bed on wheels up to much faster stuff as long as it went through MOT. I hear they are also becoming more restrictive now.

In the US, rules differ from one State to the other and the car's year of manuacture is also an important point. But they mainly check emissions and security stuff, a bit ala MOT I guess. If your car is compliant, then you can drive it. My '62 W111 Coupe is fitted with  euro 5.0L M117, 5 speed manual trans, EFI, brakes and suspension from later W108 models and it just goes through the DMV with no problem.  In France, the "Controle Technique" would fail your car and report you to the authorities (they have to).

[mkbull]

Nothing changed - here in UK - we can still drive a "tub or a bed on wheels" - We call these American cars......

[JimmyC]

David, I have been following your progress and seriously thinking of putting a M272 engine in a Pagoda because of the simultaneous increase in performance and economical driving.  I see you are quite advanced in putting your car back together again, but I would be interested in knowing what you found out about the main difficulties associated with electronics in fitting a late production V6 into a Pagoda.    That is the major concern of mine. 

[Erik]

Hello David,

When I was to install a modern engine in my 230SL it would have to be a M103.140.
I find that a Pagode shoud be fitted, at all times, with a small size Mercedes six-in-line petrol engine.
The more recent V6’s are very fine engines indeed and they are better for the environment and so on but for histories sake, let it be a six in line.
The 2600 cc variant produces a nice 160 hp and even a bit more if you can get hold of an older version without the catalyst.
Most of these cars were delivered with a 722 series 4 speed auto box which, just like the Pagode, takes off in 2nd.
Over 150.000 W124’s were produced with that engine (1984-1992) so it can’t be hard to find a good mileage car. A 1987  E260 automatic can be bought in Germany for about 1500 euro, and you get the whole car for that money.
The original engine of my 230sl is undergoing a rebuilt now but I sure would want have a go in a Pagode fitted with that E260 engine.

Greetings,
Erik

[DavidBrough]

Hi Erik & Jimmy,

My rebuild is coming on apace now and I've decided to put it back as standard for the time being as it's been so long off the road I just want it running again. When its finished I will do some more reasearch on a different engine as I would like a modern electronic engine and auto gearbox. From what I understand to date, if you take a power unit set up from a donor car with all the original electronics then you will need to reprogram the set up for differing weights and exhaust. There is a company here in the UK that already do that for Land Rovers so I intend to speak to them and see if they can do it for a Merc.

[stickandrudderman]

David,
The electronics will not care what car they're fitted to, as long as you have it all from the donor car there shouldn't be a problem.
You could experiment with spring rates to get the handling right with the change in engine weight.