Mercedes SLK320/350 LHD unique 3.7v6 not SLK32 amg/SLK320 | eBay

Rare.
I think I read somewhere they are simply bored out 6 or 7 mm.
Left hand drive as well.....shame its in the UK.

 

The description says motor swap from a 2002 SL350. "Better than an SLK32 AMG" (for tax and MOT). lol
Unique, but I'll stick with my OEM AMG motor.

 

for the cost involved in doing this 245bhp really doesn't sound like a worthwhile return

 

The Crossfire looks better.

 

OEM engine was damaged, I think that is the only reason, at least I hope so...

 

Apologies for other SRT6 owners who have "heard it all before"....

Here's what is apparently the "bee's knees" or the "ducks guts" of the 3.7L in a C32. Hin Yu's Tawain vased 500-550bhp 3.7L C32 ....(click)

Key here is the interchanngeability of the parts - heads, valves, cams, sumps and charger.....
Note - I'm guessing by the times, they had some more work to do to extrract some better times....
Although I did read elsewhere that the 3.7L M112 walls maybe getting a little thin for "long lifetime boosted" applications....well these guys didnt really let that stop them.

PS
some info on our blocks and the sleaves/treatments employed here...(click).

 

didnt someone somewhere say you could bore out our engines to 3.7?

 

hmmm....might not be that easy judging by the link in the previous post under the post script = "PS"
and again here (click) for convenience....
Thay appear to be sleaved and surface treated - but others may know better.

 

I think relegate this thread/idea to;
....1) someone with a 350 - and wack one our 2nd hand chargers on it.
....2) If you hate your money even more and your crossfire motor needs a rebuild....buy a rebuilt 350 motor (3.7L) and drop it in - then stick the old charger on it.

But nice to know the parts are easily swapped around
eg: the fact the the M113 pistons would fit a 350 is nice to know - for someone....

 

I'm still tuggin on this thread.....(dog with a bone)

So Wiki lists the M112 E37 engine (3.7L) as applicable to.....
2003–2005 ML350
2003–2006 S350
2003-2006 SL350

So I had a dig around and it would appear the 3.7L version of the ML350 sits mainly in the W163 models and is the most common and hence the easiest and (I presume) the cheapest to source.
Low km would be the key here, unless your going for a full strip down.

I found this with 77k mile engine for example,
Mercedes Benz ML350 W163 2004 Engine Tested Motor | eBay

just up the road (about 2hrs) from me as well.....
Would still need to do a fnial check on all the mounting and tranny bolts to see if they are identical, sometimes the slightest variants can cause a major PITA.
A knowledge of engine numbers would be good - I did a quick google without success.....anyone?

Idea being - pull out the 3.2L AMG core motor and put this 3.7L in and re-attach all our peripherals + charger + maybe a 178mm crank to help the charger make up for the added capacity.
Run it 'till it complains and then rebuild it with M113 AMG parts.

PS - you possibly even diligently part out some of the intake manifold etc and recoup some of your outlay.

 

Yeah but that motor has too much compression it would detonate and grenade with all that boost on it! Cam profile would be all wrong too. Search for Roger AMG....

 

Well, all these things still have been done. In this case with a Kleemann compressor. But Don't ask for the price tag.
And - if you want to build a compressor on a 3.7 stock engine, you'll first have to completely rebuild it.

Motor Umbau auf 3,8 Ltr - Umbauten, Modifikationen ... - Chrysler-Crossfire-Forum - Das Forum für Crossfirefans

If you have a AT tranny, it's much cheaper to do a 4.3, or 5.0 V8 conversion.

This one is a 5.5 V8 AMG conversion:
http://www.chrysler-crossfire-forum....otortausch-v8/

This is a 5.0 V8 MT conversion:
http://www.chrysler-crossfire-forum....chaltgetriebe/

Regards
Markus

 

Thanks BigBlock!
My google translate doesnt convert that well but I get the idea on KevCostner's 3.7/3.8L.
Great job! - but I coldnt work out why he didnt use the stock IHI charger.
The pictures are very small so its difficult to see (maybe I have to be registered).

In the 12 months I've been coming here, V8's have been covered more so than the 3.7L M112 E37.
Hence why I thought this thread would be good.
I was hoping the E37 would be a simple bolt in swap (incl heads)...

Tunaglove.....
Why do you think the compression would be different?
Apart from some cam tinkering....I thought compression ratio was mainly constrained by stroke and null space. The 3.7 has the same stoke as the 3.2L and virtually the same null space....??

You may be correct on the ML350 having a different cam setup....do you think it might be tuned for more lower end torque for the larger mass....(?)..requires more investigation I guess.

Back to the story....3.7L.....

After reading KevCostner's 3.7L rebuild that bigblock posted .....he's done a full rebuild.
I was hoping we might be able to avoid that....
I havent gotten to the bottom of it yet - but I think he mentions the crank is okay but the pistons and rods were to be changed as the originals were "not forged"????
Sorry ....my germenglish is not very good....

interesting

PS - I'm thinking this is not the real Kevin Costner hey....;>)

 

Hi Billy22Bob,

Kevcostner owned the Kleemann compressor beofre he does the 3.8 conversion. Also this compressor that the ability to produce more pressure. His goal was 450+ HP and 500+ Nm. At the moment the car is running at 0.9 bar with a lot more than these numbers.

The E37 is a simple swap, because it's the same M112 engine - same housing, same size ect. If you want to swap you have to make shure that the new engine has the same transmission than the actual engine has. In other words, a MT won't fit to an AT tranny, and vice versa.

You have to use the Crossfire ECU and give it a 3.7 ECU tune. A MB ECU will run you into different problems. The engine should be from production year 2003 - 2006. Don't expect too much horsepower and torque. These engines are good runners, but no power beasts.

You can see the pictures in full size if you are registered.

Regards
Markus

 

Copy and paste of a similar discussion I'm having over at the SLK board here...(click)...

-----------------------------------------------------------
Yes - I've been kicking that can around over at the Xfire Forum.

Suggesting is that - if your AMG 3.2L is clapped out, instead of a rebuild possibly find a 3.7L Engine from an ML350 circa 2003-2005 with the M112 E37 motor and the block/heads should transplant directly.
Then plonk the old IHI charger directly back on it at 14psi boost and you should get 335rwhp off the baseline and the commensurate increase in torque offered by the +15% increase in displacement.

Then it depends on some finer details if you want to go upping the ante and hit the 20+ psi numbers the Xfire guys are hitting.

The M113 E50 (5L) AMG or E55 (5.5L) AMG 97mm pistons drop straight in but the E50 is the only one with the same stroke, so I'm not sure yet on the technicalities of a conrod/bearing crank swap.

I actually did quick search and found a spare M112 E37 motor in Gosford in Australia with 70k miles on it.....got me excited ...well just for a minute anyways until I realised my 3.2L motor is fine....but I am a hoarder and having a 3.7L sitting around in the yard "for 'ron" (later on) was a tempting thought for the day at least.

A couple of questions have been raised....
1) the cams would need to be checked on the ML350's in question as they might be of a different tune. Blown motors reportedly go for an increase in valve overlap. And it was a 4WD you are getting it from. Not sure if a cam replacement is easy on these things without having to remove the front timing cover - but you could possibly drop your old 3.2L cams in.
2) Not sure in differences between the "forged" versus "other" pistons and conrods for >330rwhp at 6200rpm. I figured fortune favours the brave - give it a go and if you fail, you still have the old block sitting there without a piston sitting halfway embeded in the block...;>)
3) A question was raised about the tranny as far as lining up - probably do a little more homework - but if its a 722.6, just need to double check the bell housing.
4) for the crossfire guys there is an ECU issue mentioned. Have to dig a bit deeper into that one.
------------------------------------------------------------------

b22b

 

Did a quick check on Parts.com and attached the 2 engine parts diagrams for the 2003 ML350 v 2003 SLK32 for ref.

I checked prices against each other but that wasnt very conclusive.
The inlet and exhaust valves were identically matched (in price at least).

It would be good to have a similar search engine that reported back part numbers (MBenze or Mopar)
But I dont know of such an animal - links appreciated.
Of course if they have the same PN, that's a good thing, if they have different PN's then I guess you gotta dig a bit deeper to determine if they really are different.

later I found the second image for the SLK320 v SLK32 but it doesnt have cam/crank detail

 

What you need is the Mercedes-Benz EPC (electronic parts catalogue) software.

Regards
Markus

 

soundz good - I do have a PM....;>)

ok - found it...tah
epc.startekinfo.com/epc/welcome.jsp


talk about teaching a man to fish...!
b22b

 

Hopefully I'm not telling anyone to suck eggs here....

Ok....So I've been looking at whether the IHI blower would do 'da bidness in regards to pumping up a 3.7L M112 E37 such as you'd find in this SLK350.....or as I've covered already - the ML350 circa 2003-5 dropped into an SRT-6 or SLK32...or even a C32 for that mater.

Well - many thanks to Boostmonkey and Grip Grip for their data, so I had to look at the capacity of our current IHI blower. If you've read the previous posts, a Kleemann was added to the one in Taiwan. But I wanted to look at a simply "block swap" of the E37 with the E32.

Well....I'm pretty happy with the changes/improvements I've made to my model as a result of Boostmonkeys posted data here;
https://www.crossfireforum.org/forum...k-pulleys.html

As a result of this work I know the volume output of the IHI is around 1.6L/rev at 13-15,000rpm. I also mentioned the principal at work here....(no boasting intended) - the SC pumps so much air in ....the cylinders have to take it away...if they cant, the pressure increases in the plenum until they can. Simple?...hope so.

Just a note on engine capacity. Although our motors are a 3.2L, the actual volume including the "clearance volume" above the top of the cylinder for 9:1 compression is 3.60L. Likewise with an E37 with a compression ratio of 10:1 the total capacity is 4.12L - or a difference of +16%.

So when you go from a 3.2L capacity E32 engine and wack in a 3.7L E37....suddenly the engine can "take away" 16% more volume each cycle....so what happens to the plenum pressure for the same SC speed ...it drops. What does this do to horse power?....more air + lower pressure....has the total mass of feed air increased??? Because if air has increased...for a set 12AFR...that means more fuel = hopefully more hp.

So I ran some numbers through my model....
---I've assumed stock air intake setup at 448cfm for 15"WG
---At 6000rpm
---a 50C (122F) post IC intake temp
---which requires the cooler to extract about 10kW (34k BTU's/hr) of heat from the charge.
---Tranny loss = 18%
---Sea Level
---SC eff. locked at 65%.

......Setup........
Engine.....Pulleys.......MAP........IAT........... .additional.................intake air
............................psi..........degF..... .cooling required (kBTU/hr)....cfm........rwhp
E32.........74/155......12.8.......122..............0.(0)........ ...............636........290
E32.........62/155......20.1.......122............14.(48)........ ..............805........341
E37.........74/155.......9.1.........95..............0.(0)....... ................658........306
E37.........65/155......13.6.......122..............3.(10)....... ..............749.........333
E37.........62/155......15.4.......122..............7.(23)....... ..............798.........347


short story long....
the bigger E37 block will run a comparitively lower pressure for the same rwhp
That's probably a good thing given the 10:1 compression. The compression could possibly be lowered back to 9:1 by adding roughly 0.0046" (1.2mm) to the deck height. This only reduces rwhp by 1hp.
As a result intake temps are lower and the whole environment is better.
Because the SC pressure ratio is down, the SC is operating in a better zone and this may afford another 5-7rwhp and we're not pushing the SC into realms past where the current E32+62/155 guys are upto.

If you're feeling really adventurous - some fantasy numbers

......Setup........
Engine.....Pulleys.......MAP........IAT........... .additional.................intake air
............................psi..........degF..... .cooling required (kBTU/hr)....cfm........rwhp
E32.........62/178......20.9........122...........20.( 68)......................955........392
E37.........62/178......27.1........122...........30.(137)....... ..............966........384

Probably need to redo with SC eff. in as well as this is right out there. 32Krazy indicated the SC was running out of legs in a 65/178 >6200rpm stacked setup

I still need to look at the bottom end of the E37.
I also still need to look at the cam setup, but that doesnt hold as much worry much any more as swaping over I' ve discovered isnt as bigger deal as I first thought.

b22b

 

My project:
My New Project - MBWorld.org Forums

still under construction, no time for the car but it is going right.
first and only 32K with 3.7L plus 55k SC.
stock pulleys with 3 cylinder between 90 and 120psi it made 555hp crank. now i have finished rebuilt the engine, next week dyno on stock pulleys and 550cc injectors, then after 180mm pulley plus 750cc injectors plus meth. we'll see how much it will made.