Billy's W124 Coupe Project

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BillyW124

MB Enthusiast
Joined
Oct 22, 2010
Messages
2,892
Location
North West London
Car
W124 E320 coupe, W211 E320 V6 CDI, W211 E63 V8 AMG, R129 SL 280 V6, W215 CL 600 V12 Bi Turbo.
Hello Chaps,

After much umming, arring and mind changing over the last year or so I’ve been toying with the idea to ditch my perfectly running no – nonsense, exactly what it says on the tin 2.2 M111 swapping it for a 3.2 M104.

The 4 pot has served me well up until now and I expect the 6 pot to serve me better. I have no doubts that it will. Would it have been easier and cheaper to have gone out, sold my current car and bought a 320 Coupe – yes. Would it have given me the same fulfillment – No. Besides, I’ve done quite a bit of work on the coupe already to let it go like that.

The M104 will also give me better options available to me in terms of performance upgrades down the line should I consider something like it!? For now though, I’ll be a happy chappy with an unmodified straight six.

So, the engine conversion marks the start of various mods that I have been planning since I’ve owned my coupe. This includes exterior stuff, interior mods and a few other things up its sleeve.

In fact in all honesty an engine mod was last on my list!

The M104 320 lump for the conversion is from an early 1993 320E with just 99k on the clock. Although there's not a huge difference between an early 320 and an M104 from a 1995, I believe the stand out differences between the two engines are the early ones maybe are a little less ‘electronically’ managed than the later ones. Also the donor car came with no A/C which would help things along as my coupe hasn’t got it either.

The donor car I bought was spotted out of chance trawling through the net at a cheap price. The engine has a solid history which has been well maintained with the dreaded wiring loom and head gasket being replaced, all of which is documented In the service pouch. It did have its issue as advertised with an intermittent cutting out problem hence the price. The engine would fire up then cut out when it wanted to. The owner from who I bought it off had intentions to fix it but he had two other lovely merc’s and didn’t have the time to mess around with this one. Knowing this intermittent cut out issue I still bought it….after all how hard could it be fault finding it?

Dropped the car to Simon (Carat 3.6) one Sunday evening on the back of the trailer and promised me that we’ll have her up and running. Getting it up and running he did indeed. We both suspected the fault to be a possible fuel pump relay issue. This wasn’t the case, then we hoped it to be the OVP relay among the other likely causes. It wasn’t these either. Moved on to ECU diagnosis. At this time I was beginning to touch cloth…

Turns out the ECU had been opened up and repaired previously more than once! However the company who repaired the thing had no info on what they actually had done to it. So had the ECU tested and was all clear but it read 76 faults! Being the nut case I am, I kindly asked Simon to do away with this piece of junk and I got on the case for a replacement pronto. There was no way I’m having a bodged up ECU even if repaired (again) that there was a slight chance of it messing up in the future. Besides I want my 6cyl M104 experience to be blissful not hampered. I got the ECU sourced from the good chaps @ German SPOB and guess what….The car still cut out!

Not all bad though, this ECU actually read what the fault was which the old one didn’t. We think that the old de-grading loom sparked something in the ignition circuit causing the cutting out problem. (I suspect this is why the loom was changed by the owner before the chap I bought it off in the first place) A bit of soldering and by passing (?) later the engine is running sweet with no issues. I’m sure Simon can elaborate more on the fix then I can! All I know is that I’ve got an ECU that works and an engine that doesn’t cut out!

...Roll on the conversion. :rock:
 
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When is the engine going in Billy?It`ll be nice to take for a good drive,Bournemouth maybe :D
 
When is the engine going in Billy?It`ll be nice to take for a good drive,Bournemouth maybe :D


Honestly Dash I cant wait till its finished! Dropping my car off this weekend so the conversion will be taking place sometime this month. However not rushing Simon as theres a lot to get through.

Before the lump goes in there's plenty of bits that will be replaced. Still awaitng some parts that should hopefully arrive this week from MK stock to complete the stuff already picked up.

Bournemouth sounds good indeed, you already think i have a heavy right foot, so i assume we could get there quicker in a 3.2?? ;)

We're ditching the air pump, having a de-cat, keeping my existing 2.2 diff and fitting that Sebring back box i bought from you all so long ago!!

Keeping the lower ratio'd diff from the 2.2 could be well pleasing. Ok so i'll loose top end speed, who cares! Acceleration speed sounds more appealing. :)
 
If you don't mind my asking. what's the difference in ratios, and which air pump are you ditching? This gets more interesting by the minute.
 
Whats the plan after the engine transplant billy?

Im looking forward to photos!
 
If you don't mind my asking. what's the difference in ratios, and which air pump are you ditching? This gets more interesting by the minute.

I'm not exactly sure the difference in numbers but i do know they are geared up different.

The 2.2 diff will be lower ratio and the 3.2 will be higher. The differences between the two means that at top end the 3.2 diff can keep up with the engine out put where as the 2.2 won't be as its gear'd lower hence me losing top end but giving me more acceleration speed.

Someone could probably explain that a little better than me :eek:

The air pump is the thing that makes the whirring sound everytime you start up. The sound then dies down as the pump stops. You heard it?

Its basically to pump air into the cat to warm it up quicker I think?

Its somthing to do with the emissions side of things anyway, but seeing as we are ditching the cat we dont need the pump. Also by removing it, it will give me a few extra HP's.




Whats the plan after the engine transplant billy?

Im looking forward to photos!

Interior mods have been waiting in the winds for some time now so i think at this stage that may be next...?
 
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What interior changes are you making?

Scott
 
Its basically to pump air into the cat to warm it up quicker I think?

Its somthing to do with the emissions side of things anyway, but seeing as we are ditching the cat we dont need the pump. Also by removing it, it will give me a few extra HP's.


Ah I wondered because I'm having a cat back system put on my 320 tomorrow, will have to check more on what kind it is, I know its not as restrictive as a normal cat. I might be able to do away with said air pump.
 
What interior changes are you making?

Scott

The interior was going to be the first on my list. I made a start a while back by firstly installing a wood leather steering wheel, dipping rear view mirror, illuminated vanity mirrors, electric rear blind and most recently the rear storage roll top box for the rear seats ditching the middle cushion.

In addition waiting to be installed are:

  • Two front electric memory and heated seats
  • Electric reach steering column (works with memory function)
  • Fire extinguisher mounted Under passenger or driver seat
  • Infra-red locking :doh: not the most reliable systems but before i took it out of a donor i know it worked!
  • Flip top storage arm rest, the type found in US spec 124's to house a car phone. i'll use it just for extra storage purposes.
  • Speaker and stereo upgrade
But before all that happens need to strip out the old interior, laydown dynamat and noise reduction materials on the entire floor pan then run all the looms. Its going to be a total PIA!
 
The interior was going to be the first on my list. I made a start a while back by firstly installing a wood leather steering wheel, dipping rear view mirror, illuminated vanity mirrors, electric rear blind and most recently the rear storage roll top box for the rear seats ditching the middle cushion.

In addition waiting to be installed are:


[*]Flip top storage arm rest, the type found in US spec 124's to house a car phone. i'll use it just for extra storage purposes.


I have one of these Billy in black. Please be aware they are a handy thing but not as"cushioned" as a standard arm rest. I prefer not to have the tiddly bit of extra storage under my arm. However if you see one in grey leather give me a shout.

Good Luck with the project.
 
[*]Flip top storage arm rest, the type found in US spec 124's to house a car phone. i'll use it just for extra storage purposes.


I have one of these Billy in black. Please be aware they are a handy thing but not as"cushioned" as a standard arm rest. I prefer not to have the tiddly bit of extra storage under my arm. However if you see one in grey leather give me a shout.

Good Luck with the project.

My thoughts exactly John. The box needs a re trim in Mushroom as its a caramel colour bought from US ebay.

I use the arm rest quite a bit when driving so i'm not sure how this will fair?

When it goes in for the re trim i'm going to speak to the fella to add some extra padding to the lid. But if its going to distort the shape of the lid then i might forget that idea.

Have you checked out US ebay recently? There were quite a few grey ones going but they were pretty knackerd imo.

I'll keep a look out mate.
 
Hey

A bit of sea breeze mate??he he!

mazza


LOL! :)

..Based on your math mazza, The lowered springs we are using up front should be able to cope with the extra 50 - 60 KG of the M104. I'll mess around with the shim pads if it drops lower than it already is.

As the front donor shocks are in decent knick, as a temporary measure untill i get the Bilstein B8's, I'll use them as the front shocks currently on my car have seen better days.
 
I'm not exactly sure the difference in numbers but i do know they are geared up different.

The 2.2 diff will be lower ratio and the 3.2 will be higher. The differences between the two means that at top end the 3.2 diff can keep up with the engine out put where as the 2.2 won't be as its gear'd lower hence me losing top end but giving me more acceleration speed.

Someone could probably explain that a little better than me :eek:

The air pump is the thing that makes the whirring sound everytime you start up. The sound then dies down as the pump stops. You heard it?

Its basically to pump air into the cat to warm it up quicker I think?

Its somthing to do with the emissions side of things anyway, but seeing as we are ditching the cat we dont need the pump. Also by removing it, it will give me a few extra HP's.


Merc did away with that pump etc in later 320 coupe.

My late 1995 coupe does not have that fitted, so less complexity.
 
LOL! :)

..Based on your math mazza, The lowered springs we are using up front should be able to cope with the extra 50 - 60 KG of the M104. I'll mess around with the shim pads if it drops lower than it already is.

As the front donor shocks are in decent knick, as a temporary measure untill i get the Bilstein B8's, I'll use them as the front shocks currently on my car have seen better days.

Hey Billy

Yep! fine tune the stance with the spring shims and if you want, I can make you custom springs based on the template ones you are trying at the moment. You have all the spring data at the moment so its going to be a piece of cake.

We'll work out safe travel, springs rate, etc

mazza
 
Talk about doing it the hard way (not that I can talk given what i did to mine :rolleyes:).

interested in what springs you are having made - want to share more?
 
Hey Billy

Yep! fine tune the stance with the spring shims and if you want, I can make you custom springs based on the template ones you are trying at the moment. You have all the spring data at the moment so its going to be a piece of cake.

We'll work out safe travel, springs rate, etc

mazza

Yep that's the plan. Once the car is done, taking into account the extra weight of all the options like the leccy seats etc we can then go ahead and get the springs done. From the data collected previously it shoudn't be too far off the basic info we have to work with.

I'd like to be in keeping with the similar spring rate and travel to the ones we're trying at the moment.

If i remember correctly the spring rate of the ones i have is around 7.9kg/mm. Compare this to the rate of a stock spring of 5kg/mm that's quite a bit of extra capable load bearing that these can handle! I'm impressed with them considering they are only 300mm in free length Vs. 3.70 stock. Can't remember the compressed length though :eek:

I do think however taking into account 50-60kg of extra engine weight and heavy leccy seats our compressed length would need to be looked into closely and considered to be an important factor- as mentioned tryingto keep the spring travel similar to what it is now. I like to feel the the road if that makes sense?!
 
Yep that's the plan. Once the car is done, taking into account the extra weight of all the options like the leccy seats etc we can then go ahead and get the springs done. From the data collected previously it shoudn't be too far off the basic info we have to work with.

I'd like to be in keeping with the similar spring rate and travel to the ones we're trying at the moment.

If i remember correctly the spring rate of the ones i have is around 7.9kg/mm. Compare this to the rate of a stock spring of 5kg/mm that's quite a bit of extra capable load bearing that these can handle! I'm impressed with them considering they are only 300mm in free length Vs. 3.70 stock. Can't remember the compressed length though :eek:

I do think however taking into account 50-60kg of extra engine weight and heavy leccy seats our compressed length would need to be looked into closely and considered to be an important factor- as mentioned tryingto keep the spring travel similar to what it is now. I like to feel the the road if that makes sense?!

Hi mate

he he! I'm impressed mate!

I'm looking forward to see the beast


mazza
 

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