I figured I might as well document this process for those curious few. I started out doing a head gasket job on this car last year and continued modding in this thread:

https://mbworld.org/forums/w211-amg/...k-rebuild.html

Well... that was all fine and good, until I dropped an M6 washer down an intake port while putting the supercharger back on. I've had the blower off probably 20 times by now, this was just dumb luck.

Cylinder 2




Cylinder 4


Cylinder 6


Seems the washer separated and bounced around in the 5-6 seconds I had the car running after I put the blower back on.

Tore it down, assessed that the block and pistons were probably not worth reusing and set out for a solution. I could easily have picked up a junkyard M113k and thrown it in as is... but I like to tinker. I also HATE the fact that our motors are 7.9:1 compression in stock form. Having changed compression in Ford 4V modular motors in the past, I knew there was plenty of power being left on the table with the lower than low compression.

Ahmad has had pretty good results running the N/A motors with a Weistec (and previously a Kleemann), and those are sitting at 10.5:1 compression. Perfect. I wanted to find an N/A block (more importantly N/A pistons), but since this is an experiment I wanted to keep investment down. The cheapest M113 5.4L I could find ended up coming out of a 2001 ML55 AMG with unknown mileage and unknown condition. That might sound crazy, but with as far as I planned on digging into the thing, if the cylinder walls checked out I was in good shape. Besides, for what I bought it for... even if I got nothing out of it but the head castings, all I really lost was time and labor.

Before I begin, I want to thank Ahmad for his wealth of information and being available to brainstorm with me through a lot of this. He's also overnighted me his own parts when I was jammed up and didn't want to wait for the dealership.

 

Tore it down and as luck would have it, bores are in good shape! This didn't surprise me TOO much, since I've heard of M113s well over 200k without issues.


Pulled everything out, carefully documenting its placement in the original engine, I intended to put it back in the exact same place.. sort of. Some of us have seem comparisons posted by Ahmad, so I wasn't surprised to see the difference between N/A and SC


At first glance, it looks like the wrist pins are drastically smaller in the N/A piston but upon further inspection there's just a taper and the majority of the wrist pin isn't too bad. The N/A wrist pins ARE shorter than the SCs, so one would have to keep them together if they wanted to swap.


The goal was to use the high compression N/A pistons with the stronger SC rods. I mocked an assembly up to make sure this would work, disassembled, and set out to matching components.

I cleaned everything and weighed the assemblies


Here's where we ended up. Interestingly (but not surprisingly), the M113k components held a much better standard deviation throughout the range. Of course, we're talking in grams here the worst of the worst in terms of variability (M113 pistons) were really only 1.77% from mean. For reference, I've seen other production components hit 6% from mean.


The M113k, M113, and new assemblies (SC rod, NA piston/pin) come in at 1147.25, 1079.75, and 1095.875... respectively. This whooole process is important because I never intended on removing the NA crankshaft from the block and having everything rebalanced. The cylinders with the lightest NA rods received the lightest SC rods, and so on. When all said and done, I'm sitting at 1.49% from mean on the assemblies as a whole, which I'm perfectly comfortable with.



This is a pretty good start on the thread. I'm well on my way with the build so I'll catch you guys up when I have more time to properly document.

 

My 2000 ml55 has over 210,000 miles and I haven't had the engine apart but it doesn't burn any oil, no smoke and the lifters are quiet. Only issue is that the plastic has worn off of the timing sprocket and you hear a little chain noise. I would have no issues with a high millage engine, as long as it has been properly maintained.

I too have wondered why with all of these big $$$ builds nobody raises the c/r? Seems like a logical step to me? Good luck and look forward to the results

 

Subbed, so M113K block with M113 N/A pistons?

 

Glad you started a thread and I am happy to help a fellow gear head! Can't wait to see this thing run. Great way of thinking outside the box and pushing the envelope

 

nice good luck man

 

Very interesting. So the compression will still be 10.5?

 

This is going to be good bro, thanks for documenting. You going to use ARP rod bolts and head studs?

 

I'd love to see how this build goes. Although what are the limits of the NA block compared to the stock block?

 

As I mentioned in the first post, I've done this before with the Ford 4.6L modulars. I went from 8.4:1 to 9.8:1, changing nothing else but the tune, and made 70rwhp. I'm not saying this project will net the same results... or even work for that matter, but the history is there.

Nope. Here's the breakdown:

M113k rods, M113k rod bearings, M113k valve springs/retainers
M113 block, M113 crank, M113 pistons/rings, M113 heads/valves/cams
Hybrid oil pump (SL500/E55), E55 oil pan, modified E55 windage tray, ARP rod bolts/head studs

Just trying to catch up to you!

Yes, compression will be 10.5. Didn't even change the rings

Yep yep, I already had the head studs from the head gasket job last year and I picked up rod bolts for this build. These are NOT custom pieces, they're off the shelf units (with a nice, cheaper price to go along with them).

Well the block itself, I have no concerns about. I know what it takes for casting to hold power... and the Mercedes block was designed beautifully. Ahmad has had two failures on N/A long blocks and they were both rod related. By replacing those with my old SC rods, I expect to bump that internal limit up a bit. Not looking for 1000+ here, just a more efficient bolt on setup.

Back to the garage for me! I'll update today or tomorrow

 

Aren't you sacrificing displacement? The stock 55K engine (5.4L) is a stroked version of the 113 (5.0L).

Your power gain with higher compression may be a wash with less displacement.

Interested to see what happens.

Did that M6 washer come from your supercharger stand-offs?

 

The M113 I'm using is from a 2001 ML55 (5.4L) so the displacement is the same. If I had started with a 5.0L block, I would've transferred over my M113k crankshaft along with the M113k rods to retain the 5.4L displacement.

I use socket cap fasteners with M6 washers on my valve covers and surge tanks. I'll be looking into flanged head fasteners to replace them with so this doesn't happen again

 

Thanks for clearing that up, read it a few days ago but forgot about the ML55 engine. This may give you a nice bump in power (-;

 

That's somewhat ambiguous, but still in for the results and the build.

 

Wait I've been in this route before, the 55n/a piston itself is lower by 0.7mm from 55K piston, so if you use the 55n/a pistons with 55k rods you will be lower by 0.7mm from the cylinder deck, you must use the 55n/a rod with the 55n/a piston to hold the 10.5 compression ratio.
if you want to use the 55K rods a brief calculation of ur compression ratio:

Disp for all 55 engines=3.14*bore*bore*stroke/4= 3.14*97*97*92/4= 679864mm2
CR=10.5=(679864+V)/V so V 55n/a=71564mm2
the volume made by 0.7mm is 3.14*97*97*0.7/4=5170mm2
CR will be= (D+V+V0.7)/(V+V0.7)=
=(679864+71564+5170)/(71564+5170)= 9.86
assuming head volume, gasket volume and deck clearance are same.

 

Let me know what you need more clarity on..

Ah yes. This would be true if I was using the 55k block and 55k heads... but when you get through the nitty gritty I'm essentially doing a rod swap on a 55n/a engine and making it work in a W211. At the end of the day, even if I did a piston swap on a 55k and ended up with 9.86 that's good enough for me. ANYTHING is better than the damn 7.9:1 stock.

 

Oil pump.

The ML55 oil pump has one set of internal gears, a solid sprocket, an M113 oil to engine outlet, and a front sump pickup. The body and pickup is too tall for the E55 oil pan. The E55 oil pump has three sets of internal gears, an identical solid sprocket, an M113k oil to engine outlet, and twin front/rear sump pickups.




Since the E55 oil pump has a different outlet, I couldn't just add the E55 pump to the M113 block.


The solution, after a TON of research, was a modded oil pump originally for a SL500. This oil pump has the M113 oil to engine outlet and a similar sump system to the original E55, but with a larger sprocket.






If you notice, the rear sump tube system has attachment brackets to the main fasteners... but on the ML55 these were standard fasteners. I pulled the fasteners in those locations out of the E55 and they're shown below. Had new OEM fasteners overnighted from Ahmad (I'm tellin you, this guy is good), and installed them on the M113 block. You can see the finished product with the bracket fasteners installed further down the post.


I disassembled both pumps and originally wanted to use just the front casting out of the SL500, with the rest of the pump coming from the E55 pump. Unfortunately, these gear set bodies were just BARELY incompatible. Ended up with a full SL500 oil pump with the E55 solid sprocket up front.




Upper and lower oil pans went on. I didn't take pictures of the windage tray, but some modification of the windage tray was required to fit the slightly different rear sump tube system.

 

Big shoutout to the girlfriend, she's a trooper for putting up with all this. Barefoot and going to town

 

Damn its nice to read these... so much knowledge and skill

How much power are you going to get out of this, or whats your goal?

 

Cool man, way to work through it.
I'm curious how you research something like that to come up with the sl500 pump?

 

That's cool, but now who's in the kitchen?

 

Great built bro..,

Is that oil pump from SL500 R129 or R230..?

ZAYED,,

 

nice work!

 

beautiful stuff man, def a mad man for pulling that thing apart like that... props for the girl helping you out too, that's awesome. Ohh and those valve covers look ****

 

I've mentioned it before. On paper, this should be a very nice bump in power but I won't know until it's all back together and tuned.

The Mercedes EPC system, trying to get pictures from dealerships on parts in stock, online part vendors, and eBay. It was not an easy task. This may be a solution but the front sump pickup is quite a bit shorter than the stock unit so I believe I'm sacrificing about a quart of oil capacity by not more extensively modifying the pump to drop the pickup. The rear sump is the important one, it holds 3 quarts on its own and when accelerating all of the oil is moved to the rear, course.

It's summer and the man operates the grill

R230, 2004