98' W208 320 broken do any of the 350 Engine fit?

[crisc204]

My trusty CLK has thrown in the towel.
Its transmission has failed.

What to do?

£2500 purchase price 11 years ownership 80K Miles with me with no issues and it's now only got a choice of two gears Seconds and Reverse which it selects with a loud clonk.
The fault will not clear and he's got the right hump.
A few years ago Its survived an assassination attempt by another drunken Mercedes, got Zero rust and fully kitted out for competition Audio SQ events and lots of AMG and suspension goodies plus I like driving it
I think technically the cost would write off the car but as I've definitely had my moneys worth out of it I'm not grumbling.

It's being dropped off at a local Auto box specialist I use for work, he has the right test gear and has done 1000's of Mercedes boxes so I'm confident I'll have a diagnosis by end of the day.
I also have a Bodyshop & Diagnostic but not all the years of Mercedes experience these guys have.

Seeing as its broken and the Engine has 205k on there in total I was thinking out loud wondering what else slots in to a 320 V6 space.

Last couple of miles the engine balance shaft bearing area, there is a noise
from inside the timing casing even with AUX belt removed

A 3.7 engine and fresh gearbox would make it move along well...
I wanted a 32AMG Komp Engine but have been told repeatedly it's to much work it physically fits not bother the chassis can take the power but getting it running seems to be a PITA

SO do any of the Normally asp. 350 series engines fit circa 2002-2005 models?

...and is it still too difficult to fit a 32 AMG Komp engine?

Are there still no standalone ECU's that work with Mercedes kit?

Alternatively should I buy a rusty/damaged 430 and stick the V8 in there...


p.s. We have got another family car so its not super urgent, fancy bit of a project...rather that scrapping my old mate

 

[Doodle]

The answer to most of those is "Yes, it just depends on how much time and money you're willing to throw at it"

A decent standalone ECU, plus labour to configure and setup is likely to cost the same as the original purchase price, if not more.

Fitting a different Mercedes lump, especially one not normally found in the 208, is going to be a case of getting the right combination of sensors and management units all talking to each other. If you haven't got your own STAR kit this will quickly devour money in garage fees.

How much is sentimentality worth to you?

 

[John Jones Jr]

SO do any of the Normally asp. 350 series engines fit circa 2002-2005 models?

Considering it's a M112 just as you're 320 is, I guess the 350 (3.7) would drop in and mate to your current g/box. If so what would be very handy is if you could use your old engine wiring loom and ECU. Presuming the 3.7 fits, what you'll then need to know is if the 3.2 ECU can handle the new engine as regards fueling etc, even if it can't fully a remap may solve that issue.

All guess work on behalf but on the face of it, it does seem like a practical transplant.

P.s. personally I wouldn't consider transplanting a V8.

 

[rorf]

The 350 is definitely no M112 and uses the 7G box with associated electronics and is a much more complicated engine.

Your best bet is a M113 V8 with the 5G box (55 AMG) - this has been done and you will find the info on the various Mercedes forums.

Surprised your 98 W208 lasted this long, the later models were much more reliable and more efficient technically wise.

Good luck

 

[PobodY]

The answer to most of those is "Yes, it just depends on how much time and money you're willing to throw at it"

A decent standalone ECU, plus labour to configure and setup is likely to cost the same as the original purchase price, if not more.

Totally agree. - You stand to lose some of the original functionality with a standalone ECU, but you potentially gain the ability to add other features... and other engines.

So, as above; it just depends how much time and money you're willing to throw at it.

 

[John Jones Jr]

Duplicate.

 

[John Jones Jr]

The 350 is definitely no M112 and uses the 7G box with associated electronics and is a much more complicated engine.

I beg to differ. The 350/3.7l is part of the M112 engine family. Basically the 350 known as an E37 (whereas the 320 is a E32) is an overbored 320.

As for the 7G box it's very possibly irrelevant as the original g/box should mate to the 350 engine.

If I'm correct on the above the 350 should drop in and installation could be straightforward using the 320 loom, ECU, MAF and Throttle Body etc. Negating the need for a costly and time consuming Standalone ECUs, wiring harness and associated sensors.

If nothing else the 350 installation is certainly worth looking into as could be the cheapest and most practical transplant, plus I can't imagine there is a great demand for used 350 engines.

 

[mark_le_b]

If you do use a 350 engine, just make sure it's new enough not to have the balance shaft issue

 

[crisc204]

I beg to differ. The 350/3.7l is part of the M112 engine family. Basically the 350 known as an E37 (whereas the 320 is a E32) is an overbored 320.

As for the 7G box it's very possibly irrelevant as the original g/box should mate to the 350 engine.

If I'm correct on the above the 350 should drop in and installation could be straightforward using the 320 loom, ECU, MAF and Throttle Body etc. Negating the need for a costly and time consuming Standalone ECUs, wiring harness and associated sensors.

If nothing else the 350 installation is certainly worth looking into as could be the cheapest and most practical transplant, plus I can't imagine there is a great demand for used 350 engines.

This is the line of thought I was on

I really want it to be on a Mercedes Electronic Key
So will try this avenue first

The 350 is definitely no M112 and uses the 7G box with associated electronics and is a much more complicated engine.

Your best bet is a M113 V8 with the 5G box (55 AMG) - this has been done and you will find the info on the various Mercedes forums.

Surprised your 98 W208 lasted this long, the later models were much more reliable and more efficient technically wise.

Good luck

See I don't get the bad rep, mine was number 1880 probably one of the first batch of RHD out of the gates actually 1997 now i've been looking at all the paperwork.
Literally never had an mechanical issue out side servicing the car and I broke a Key once.
IMHO Most of it is that they are very definitely not continuation of a W124...

From quick research I think there is a 350SL with 7G box and 350 S class with 5G which is smaller 3.5 maybe

Both look the same as my old 3.2 eg Not twin cam heads, not variable timing, same Ancillaries, same inlet manifold
Only some extra air pump thing for emissions

It's worth a look even if it needs more work as I don't see why a Conversion belhousing and finding the right Torque converter couldn't make a 320 box fit a 3.7 SL350 or... that's relatively simple
...if it needs higher rating a 430 5G

Most of this can be worked out on paper long before I spill any oil...

 

[crisc204]

One other thing I find it strange I have not come across an aftermarket ECU product that works with Mercedes Architecture to keep all the other systems intact.

If it went over to aftermarket ECU
Not sure how the MB Auto box ECU would work without the MB Engine ECU
Engine, Transmission, Traction, Stability all linked.

Anyone know of an aftermarket ECU that works with Mercedes?

BTW I have got form for tuning cars...
Can't help it, haven't grown out of it, so just accepted it!
...our little work van has +60% the factory power, double the torque and after the suspension work it's had it would put in a decent time around Brands lol
Lots of old Ford RS and old Porsche's... u get the idea

 

[John Jones Jr]

One other thing I find it strange I have not come across an aftermarket ECU product that works with Mercedes Architecture to keep all the other systems intact.

If it went over to aftermarket ECU
Not sure how the MB Auto box ECU would work without the MB Engine ECU
Engine, Transmission, Traction, Stability all linked.

Anyone know of an aftermarket ECU that works with Mercedes?

BTW I have got form for tuning cars...
Can't help it, haven't grown out of it, so just accepted it!
...our little work van has +60% the factory power, double the torque and after the suspension work it's had it would put in a decent time around Brands lol
Lots of old Ford RS and old Porsche's... u get the idea

Aftermarket Standalone ECU's and Mercedes? I've looked into it but not in depth. After getting some advice, if I was to go down that road it would be a Piggy Back ECU only limitations and all.

Do keep us posted on how you progress. In an ideal world an AMG 55 or even a 43 lump, box, diff, brakes, suspension. exhaust system etc (including getting the ECU to work in conjunction with the car's EIS) would be great I'm sure but then you may as well just buy an AMG CLK.

 

[crisc204]

Found this bit of info on wiki

S350 (in the US this was available in 2006 only; had 3.7L V6 and 5-speed Automatic transmission) [18]

Hmmm easy peasy then...wonder what the uk cars had

Now it's time to check out a few breakers yards over here

 

[crisc204]

After a bit more digging the older simpler 3.7 350 engine from S class ML 4x4 and Early SL's 03'-06' is M112 and pretty much the same as my 320.

The later C350 Clk350 3.5 engine is the one not suitable this is M272

My cousin has agreed the purchase of a 2004 SL 3.7 with the 350 engine I'm interested in with a friend of the family...

This means I get my hands on it to check out a possible conversion

If it fits its viable we are looking at about 280BHP after remapping and exhaust system tidy up and much lighter than a V8 CLK over the front axle

 

[crisc204]

Got one, complete...less the airpump on the front.
£350
Its going in soon

 

[grober]

Just to add there were several Chrysler products with that M112 engine also ---Crossfire ---Jeep etc.