M117 head/valve train mods

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M117 head/valve train mods

Post by kimrh » Tue 26 Nov, 2013 9:45 am

To answer Craig's question in new member Tim's thread re headwork etc-

The AMG 50:1 cams (modified MB cams) came out in the Gen1 500 era and they took a 500 head and modified it -
These AMG heads are standard 500 M117 Gen1 euro heads converted to mechanical lifters with early M116/117 MB bits and include the following specs:
1. The exhaust ports enlarged to 39mm (stock is 36.75mm)
2. The intake ports polished/ported
3. The combustion chamber slightly enlarged to accommodate the larger bore/displacement of the 5.4
4. The exhaust valves are stock gen1 500 M117 (39.10mm v/face)
5. The intake valves are the same size as Gen2 560 (46.20mm + were undercut in the bowl area). The original Gen 1 valves 44.20mm were swapped out
6. Valve springs are stock 117 500 MB part # 110 053 01 20
7. Modified MB retainers - milled to reduce weight (as from factory they are heavy @ 35.50grams)
8. Modified MB follower(rocker) arms - the little wings were machined off to reduce weight from 84grams to 74grams (but i have been advised it is not recommended these days as they were in the MB design for a reason.
9. Solid MB Lifters from the iron block 450 engine
10. MB M117 500 standard camshafts modified with "AMG 50:1 grind" which changes the duration (lobe separation) and ramp rate and increased valve lift over stock

To replicate starting with a Gen1 500 head as AMG did - it requires porting intake & exhaust /polishing exhaust ports and intake valve seat machining to fit 46.20mm valves

Starting with a Gen2 560 cylinder head would be less labor intensive in that little work is required other than a general tidy-up of the bowl & ports to remove casting edges (smooth them out) and slightly enlarge the exhaust port by 2mm (would be also worth port matching intake & exhaust).
When the Gen2 560 heads were released in late 86 they came standard with the bigger intake seats already and a bigger exhaust port than the stock gen1 500. They flowed tested well at 202cfm's and after some ala AMG porting and undercut intake valves it improved 240 cfm's.
The stock 560 heads flow well and will handle 400hp so they really don't need much work other than a general tidy-up and port matching.

When MB released the Gen1 4 pin 822 ECE 10:1comp 220kw engine they followed the AMG path except stuck to a roller cam and produced the 16/17 cams (same as the later gen 2 "220kw"- 24/25 cams) and went about modifying the Gen1 heads as mentioned above.

Then they released the 8 pin 220kw RUF 10:1comp engine (cams/EZL/F/Dist/dizzi/oil cooler etc)

To modify these further requires a port and polish and a mechanical conversion with all of the lightened bits if you want to drop in a pair of AMG grind 50:1 cams which have now been replicated
The lightened valve train work has been well documented and is not hard to do at home with a grinder and kitchen cooking scales if you wish to go that path.
The mechanical lifters and retainers come from the earlier version M116 engines
New cams replicating the AMG grind can be purchased in USA but then your stuck with manually adjusting gaps which is a pain versus a roller hydraulic cam which requires no ongoing maintenance.

However even better
You can go for these that retain your standard lifters (instead of the hassle of adjusting mechanical lifters)
http://feind-motorsports.myshopify.com/ ... m117-motor (since stopped making them and now made here in Australia via Mike at Dkubus)
If you have your heads out then a slight port & polish would be handy at the same time

Hope that answers a few questions for you Craig

Cheers
Kim
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Re: M117 head/valve train mods

Post by CraigB » Tue 26 Nov, 2013 11:46 am

Thanks Kim - i thought all that stuff was top secret so thanks for that. I didn't know what they did, just that mine loves to rev and just keeps pulling to fuel cutout limiter - a fact that is well supported by the amg dyno graphs of standard vs amg. I missed the price as i was reading about those cams and thought it all sounded pretty good - but that is a substantial amount of money over those cams i bought - would pay for a lot of rocker adjusting!!

My engine seems quite low mileage so it would be nice not to lift the heads if i can avoid it. Not sure if i mentioned before but i got the full 560 loom and 8 pin module yesterday, so i could theoretically keep that all standard if i wanted now. Anyway for starters i will concentrate on getting it registered and get the body work done. Its nice to do mods to stuff but if i look back there is something about having a car that maybe might not be perfect but you are using it vs the schmick modded / finished item that spends huge amounts of time being immobile - thats speaking from experience rather than having a go at anyone - it happens to us all!

I wonder if you pulled the cams and rockers for doing the conversion and so all the valves are closed - and engine out of car - could you get some sort of flexible bit, like a flap wheel to clean up the port as much as possible - blow/vacuum out - amg cams in with lightened rockers (people have suggested getting new ones). I need to pull the motor to paint it all properly anyway. ...... just thinking out loud.

And thanks for making a new thread with that Kim.
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Re: M117 head/valve train mods

Post by kimrh » Tue 26 Nov, 2013 9:05 pm

More technical info for you straight from the horses mouth
AMG modded 235kw solid lifter 9:4.1comp fully ported 16v engines with lightened valve train achieved the extra 15kw @ 5,250 rpm ( i don't think the AMG headers made much difference over the MB tri-y's)
The 6litre (100mm bores) bumped that up a bit further top 243kw @ 5,250 rpm
I have more data stored away somewhere that i will dig up
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Re: M117 head/valve train mods

Post by Panzerkampfwagen CXXVI » Fri 29 Nov, 2013 9:23 am

Good info here.

Given I have a 195kW Gen 2 M117.965 (5 litre), are the heads the same as the M117.968? (5.6 litre)

Just thinking, if I ever pull the engine down for a rebuild, I wouldn’t mind giving the ports a bit of a once over, perhaps some bigger valves… Some AMG-themed stuff without ruining the originality of the car.

I’d really love to put an aftermarket ECU on the car…. Redesign the plenum… But I want to have at least one car that’s relatively standard.
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Re: M117 head/valve train mods

Post by Panzerkampfwagen CXXVI » Fri 29 Nov, 2013 9:28 am

Furthermore, is there any information on the tuning of the AMG engines, as in any K-Jet specs?

Myself and a friend have been thinking about investing in an oscilloscope and offering a service tuning and repairing older Bosch fuel injection systems - given noone in Ballarat can do it, and the one shop that can.... well I wouldn't even take my lawnmower there, let alone a car.
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Re: M117 head/valve train mods

Post by AMG » Fri 29 Nov, 2013 3:07 pm

Ryley,

the EZL contains all the ignition table data, basically it's an UVeprom and it's difficult to get out.
I have the xeltek reader to do the work, but to remap the EZL is not straightforward - you'd have to replace it with an eeprom instead.
Given the age of the technology, it's not that great as a modifiable system.
The only thing you really need concern yourself with is the duty cycle measurements and the EHA. most of the 'fine' tuning was done by altering the differential pressures.
The ignition advance curve in the ECE ezl with the multi position resistor is your only mountain to climb. Find a way of removing the AKR and perhaps setting the EHA a tiny bit richer would help.
EHA is a very sensitive adjustment. You need to watch the differential pressures carefully too.

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Re: M117 head/valve train mods

Post by Mercmad » Fri 29 Nov, 2013 6:19 pm

Kjet is great in that it delivers the right amount fuel that the engine requires as the airflap opens. It would make sense to fit a larger throttle body to pass more air or do as Ferrari did and fit two seperate fuel distributors. Head develpment has move on a very long way since the days of AMG tuning the m117. I would get a set of heads flow tested by a compentant shop who have experience with jap tuning . Also,I would get rid of the EHA type distributor and retro fit a Kjet unit with warm up regulator. Next would be a mappable ignition to really unleash the horses.

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Re: M117 head/valve train mods

Post by kimrh » Fri 29 Nov, 2013 11:05 pm

Ryley your Gen2 500 heads are the exact same heads as the 560

Of interest besides the certain EZL's that were used for the higher performance engines in Gen2 500's & 560's (either 4 pin with manual fuel trim or 8 pin automated with knock sensors)
There were specific Fuel Distributors used on the high performance engines being model stamped 0438101016 (standard gen2 8 uses 0438101018)
Both my 500 & 560 engines have this same fuel distributor and that same FD was used on the later R129 SL500 M119 engine.

The 560 valves (part # 117-050-0126) are the same size as the AMG 500 valves = 46.20mm
Though the AMG intake valves tops are lightened/concave as shown in the pics and valve stem under-cut in the intake bowl area to increase flow and reduce weight
500 head intake ports measure 41.0mm
560 head intake ports measured 41.35mm; AMG 500 ported to 41.50mm

560 exhaust valves (sodium filled) measure 39.10mm (same as gen1 500 head) part # 117-050-0127 and AMG did not modify these valves so same spec
500 head exhaust port 37mm
560 head exhaust ports measured 37mm ; AMG 500 ported to 39.5mm

560 upper and lower manifold ports all measured at 40mm;
AMG 500 measured 41mm / 41.5mm.

The 560 heads require very minor material removal and the only significant difference was the exhaust ports on AMG heads were 2.5mm larger
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Re: M117 head/valve train mods

Post by kimrh » Fri 29 Nov, 2013 11:11 pm

AMG 50:1 Cams / Lightened valve spring retainers (factory weight 35.50grams)
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Re: M117 head/valve train mods

Post by kimrh » Fri 29 Nov, 2013 11:42 pm

Of much interest Mercedes factory produced the M117 5ltre twin KKK turbo race engine that was fitted to the Sauber C8 Group C prototype race car
Now that would be an interesting research to find out the specs of that prepped engine and its power/torque output!!

Quote:
Mercedes decided not to put forth the money for a full effort on their own until they had time to develop the production-based M117 5.0L Turbocharged V8. Therefore, Mercedes turned to Sauber to create a chassis for them and initially to run the team before Mercedes took on a larger role. Sauber chose to evolve the previous C7 prototype for the C8, although modifications were needed to house the larger V8 instead of the C7's previous Inline-6.

In its debut at the 1985 24 Hours of Le Mans, Sauber was able to qualify 17th. However, the car suffered an accident later in the race week that caused enough damage that the car was not able to participate in the race. The team promised to appear at a few more races in the World Sportscar Championship season, but never showed.

For 1986, the team became known as Kouros Racing Team, and the C8 was entered in the full season of the 1986 World Sportscar Championship season. For the first two races the C8 showed promise, with an 8th and a 9th. However later in the season two C8s were entered in the 1986 24 Hours of Le Mans where unfortunately neither car was able to finish. For the 1000km of Nürburgring, the team was able to achieve its first victory with drivers Henri Pescarolo and Mike Thackwell, made all the more important by being won in front of the Mercedes-Benz executives in attendance. With this victory the Kouros Racing Team was able to end the season 5th in the teams championship.

In 1987, the Kouros team switched to the newer Sauber C9, while C8 chassis #2 was sold to privateer French team Noël del Bello, which entered the 1987 24 Hours of Le Mans and 1000km of Nürburgring, but failed to finish either race. Noël del Bello continued into 1988, but failed to finish any of the races it entered again. Unquote: (note: the Sauber C9 race car introduced the M119 engine)
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Re: M117 head/valve train mods

Post by kimrh » Mon 25 Dec, 2017 3:55 am

I have revived this old thread for those of recent times who are curious about the various M117 heads and how they performed versus what AMG did back in the day.
I have added in some more content to the original posts with more specs

The Gen1 heads flow very adequate for a 500 engine and produce great torque where you need it on the street (the intake valves are only 2mm smaller than a 560 head and exhaust valves the same.

What AMG did to the Gen1 500 head was basically what MB followed with the Gen2 heads which increased flow for top end power versus the gen1 head.
If fitting bigger custom cams both the Gen1 500 engine or a the Gen2 500/560 (same heads) either can handle them without being a restriction to either engine.

The main restriction in either engine in terms of flow is the intake manifold plenum chamber which lets both engines down if chasing increased top end power from either engine with mods like bigger cams (no adverse affect on a stock engine but perhaps on an MB 300hp engine top end power curve)

Mike at dkubus in Adelaide with his 500SL gen1 track car with its un-opened stock gen1 500 engine (other than big cams/high stall converter & custom free flowing exhaust with no cats and his Franken-CIS tune has been achieving great results from that engine which continually sees 7,000rpm under very trying track conditions running big 18 x 13wide rear rims & massive sticky track tyres which he breaks traction very easily.

So nothing wrong with a free revving Gen1 500 engine (M117-961-962-963-964) or the Gen2 500 high comp or the stroker 560 for more torque without really needing to modify the heads of any of the engines if chasing more power with custom mods.
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Re: M117 head/valve train mods

Post by CraigB » Mon 25 Dec, 2017 8:32 am

I can't remember what was there first time and what added - amazing detail - thanks for the Xmas pressy!

And what were you doing up so late..... waiting to catch Santa?
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Re: M117 head/valve train mods

Post by kimrh » Tue 26 Dec, 2017 1:31 pm

Ha-Ha we had a late night and i was having a coffee before bed and had some data written down on paper that i had on my mind as have been discussing/playing/measuring with heads with my local engine machining shop - he has 3 sets of my Gen1 500 heads down there at present which have been fully refurbed.

I am pressing on with a custom valve train set ordered in from USA - new Ferrea Comp Plus Pro racing alloy undercut 46.2mm intake valves/ Ti retainers both intake/exhaust/beehive springs both intake/exhaust etc which reduces significant weight >50grams on intake and 35grams on exhaust and a set of my 500 or 560 heads will most likely be worked over (port/polish) with this Kit installed.
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Re: M117 head/valve train mods

Post by CraigB » Tue 26 Dec, 2017 3:45 pm

This is a great reference thread. Any chance you could put part numbers at some stage of what you are using? Also, I have a list of questions that could go back in the thread as an edit (assuming they are not stupid questions!)
  • Great pic of lightened retainer - you said 'factory weight 35.50g - is that AMG factory or MB factory? Would be great to know the target weight and then turn down until you get to that desired weight
    Porting pic 1 - Inlet? What is the bit that is projecting down? Is that where the injector sits? Doesn't look like injector but is it a plug to protect the hole?
    Porting pic 2 - is that the guide towards the bottom of the pic? It looks odd but wondering if some sort of optical illusion.
    Porting pic 3 - must be inlet and hole for injector
where were the porting pics taken - your engine builder?
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Re: M117 head/valve train mods

Post by kimrh » Tue 26 Dec, 2017 6:52 pm

Craig those original port pics posted up in 2013 were taken some yrs ago of Henric (aka: AMG Classic Forum) heads off his Gen1 5.4 litre original AMG spec engine that was rebuilt.
The pics show the port & bowl area from viewing through the intake port and above with the intake valve removed.
The little v bit of metal left untouched is bridge between the injector hole and the valve guide with the rest around the guide blended in.
If it looks odd it is just the camera angle and light source creating reflection perhaps.

Here is a shot of a stock Gen1 intake port and a Gen2 intake port with the valve removed and not cleaned up
Plus some pics of the new valve train custom made parts i am getting in from USA (Intake valves are Ferrea Competition Plus Pro racing alloy valves that are custom made to spec for the M17 head, custom made Ti retainers, custom made Beehive springs.
None of this stuff increases power (Other than the undercut intake valves improving intake CFM flow with less resistance of the valve stem and better multiple back cuts to the valve for improved flow) but it certainly lightens up the valve train inertia significantly for a more free revving engine and combined with the bigger cams i am sourcing the combo should work well together with custom tune via the Dkubus Franken-CIS Kit
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Re: M117 head/valve train mods

Post by kimrh » Wed 27 Dec, 2017 1:52 pm

Here are some pics of a Gen1 500 head intake ported to AMG spec and the AMG 46.2mm valves installed
As you can see the 46.20mm (same as came out in the Gen2 head for 500/560) takes up all the available space in the combustion chamber.

Also a pic of the standard factory follower weight (84 grams) versus the ground down wing-less modded version to AMG spec (74.0 grams)
Interesting i have been told by an engine builder not to machine these rockers down like AMG did as it is now believed it compromises the follower design (as in the wings were put there for a reason) but i suppose the wing weight is at the mid point of the arm fulcrum so in theory inertia weight is only half that extra 10 grams (ie: 5 grams)
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Re: M117 head/valve train mods

Post by 3doghouse » Wed 27 Dec, 2017 2:43 pm

Thank you for reviving this thread. It is packed with great detail, but one of the things I haven't seen explained is the limitation to the valve lift in M117 heads.

It seems that all of the aftermarket cams produced over the years stay close to stock lift numbers. Is this because of coil bind, piston interference, or something else? Would different springs allow more lift?

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Re: M117 head/valve train mods

Post by Tony From West Oz » Wed 27 Dec, 2017 2:50 pm

3doghouse wrote:
Wed 27 Dec, 2017 2:43 pm
Thank you for reviving this thread. It is packed with great detail, but one of the things I haven't seen explained is the limitation to the valve lift in M117 heads.

It seems that all of the aftermarket cams produced over the years stay close to stock lift numbers. Is this because of coil bind, piston interference, or something else? Would different springs allow more lift?
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Re: M117 head/valve train mods

Post by kimrh » Wed 27 Dec, 2017 10:47 pm

Good question as cam specs has always been a bit of a mystery as to the science behind it.
These M116/117 are an interference engine - meaning at TDC the open valve to piston clearance is tight!!!
When you look at the 10:1 high compression pistons crown it is machined to allow room for the valves (see pic below of my spares) so increasing lift is very limited.
Max lift of any valve has to be kept under 0.500 to not interfere with pistons
Max lobe size is restricted by cam journals/bearings
It is a science to avoid tall lobes with too steep ramps (result of keeping duration (overlap) in check to avoid premature wear

So here is some info on cams-

I don't have the MB 300hp cam specs handy as to max lift
Only have what they state in the workshop manual
Measured at 2mm of valve lift on intake valve- No 1 cylinder =
Intake opens ATDC left cam 17* / right 16* closes ABDC left 41* / right 40*
Exhaust opens before BDC intake left 33* / right 34* - closes BTDC left 9* / right 10*

AMG solid cam specs as seen in the AMG Gen1 engines
@ 50" = 232 duration with .297 lift

AMG Stage3 Roller cam - Later on when the Gen2 560 engines came on the scene AMG did release a very little known Roller cam known as "AMG stage3" cam to suit the factory hydraulic compensators and avoid the need for manual gapping of cam followers (rockers)
Intake: 237 duration @ .050" = .421 lift
Exhaust: 244 duration @ .050” = .440 lift

Feind 276 duration roller Cams (no longer in production) but the same cam spec is now produced locally here in Australia by Dkubus.
Feind/Dkubus Roller cam : 276 duration / .301 lift
Cam card Spec – m117 "street cams"
Valve clearance (hot) intake 0/exh 0 and (cold) intake 0 /exh 0
Cam lift: intake .301 / exh .301
Rocker arm ratio: intake 1.52 / exh 1.52
Valve lift: intake .455 exh .455
Duration @.004 intake 276 / exh 276
Duration @ .039 intake 242 / exh 242
Peak diff, max lift @ 105 ATDC 105 BTDC
Valve lift at TDC w/o clearance intake .117 exh .117
1. w/o clearance @ .004 .004
valve opens intake 31 BTDC / exh 61 BBDC
valve closes intake 65 ABDC / exh 35 ATDC
2. w/o clearance @ .039 .039
valve opens intake 16 BTDC / exh 46 BBDC
valve closes intake 46 ABDC / exh 16 ATDC
note: B/A TDC = before/after top dead center
B/A BDC = before/after bottom dead center
These are a little more aggressive than the AMG profiles
The AMG solid Cam was 232 duration and .297 lift
The Dkubus cams open sooner but ramp slower than the AMG solid cams.
These dkubus cams aren't copies of the AMG profiles for the reasons listed, but they were used as a reference for numbers.
These dkubus cams are designed from the ground up as a new profile to work with factory hydraulics.
They do have a longer duration, but part of that is the longer slope of the lobe, so as to "not need" to convert to solid lifters.

The factory hydraulic roller cams have steep slopes due to less duration to avoid overlap and produce a smooth running engine which is a compromise between power and economy and meeting emissions requirements.

AMG solid cam was looking for more top end power and the lobe ramps are fatter (more duration/overlap) with a bit more lift however the profile of the this cam required it to go to solid lifters (compensators)
It requires expert tuning to enable the Bosch K/KE-Jet to run otherwise it is a pig

The AMG stage3 roller cam (hydraulic) is again more duration and different ramping to suit hydraulic lifters and is a pig of cam with bosch K/Ke-Jet and requires either Franken-CIS tune or engine coverted to EFI with custom tune.

The Dkubus 276 hydraulic cams (pushing the boundries of duration (overlap) and max lift and keeping it a roller cam.
Mikes 500SL gen 1 stock engine regularly sees 7,000rpm under tough track conditions with his custom Franken-CIS tune and hi-stall converter.
The engine idles around 900 in park but 750 in drive (with that lumpy cam sound)
See video clips on his facebook page
https://www.facebook.com/DKubusKustom/v ... 5723260465

Any of the above cam changes is going to require custom tuning over a stock cam - so no avoiding that to get a stock engine performing better.

Hope that helps understand the issue with getting extra lift of the valves from custom cams
Hence why all went for more duration to keep the valve open longer to get more breathing happening

Of course if you were going the forced induction path none of this would matter!!







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Last edited by kimrh on Thu 28 Dec, 2017 6:47 pm, edited 1 time in total.
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3doghouse
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Joined: Tue 26 Dec, 2017 3:41 pm
Model you own: w107
Location: Augusta GA USA

Re: M117 head/valve train mods

Post by 3doghouse » Thu 28 Dec, 2017 8:40 am

Many thanks for your insightful and detailed reply. Looks like duration is fair game, but piston interference might as well be a brick wall!

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Tony From West Oz
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Re: M117 head/valve train mods

Post by Tony From West Oz » Thu 28 Dec, 2017 12:25 pm

If gas flow is a limiting factor, perhaps forced induction is the simplest way to gain more power.
Hmmmm. Anyone fancy a twin turbo M117? :dance:
OK that has been done already. :dontknow:
Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

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'84 W123 300D replaced good OM617 912 with OM617 952 and enjoyed having good acceleration for the first time since first driving a 300D in 2002 - became engine and trans donor for 300CD Turbodiesel conversion. Now parted out.
'86 W124 300D sold (Wife's old car - sold )
'85 W123 300CD, 275 000km (Fatmobile) rebuilt turbodiesel from previous Fatmobile transplanted into 280CE (occasional tourer)
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kimrh
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Model you own: w126
Location: Perth WA

Re: M117 head/valve train mods

Post by kimrh » Thu 28 Dec, 2017 1:43 pm

It is by far the simplest and most cost effective way of making more power out of these engines without the need for mods if you keep boost to say within a safe 8psi and the low compression versions of the M116/117 are perfect for forced induction.

Otherwise with more boost your going to need the block thread "time-serts" where the head bolts screw in. Probably ARP stud bolts and Cometic steel head gaskets (they now make them for the M116/117)
Of course with boost comes the need for some custom tuning and with retaining the factory Bosch K/KE-Jet injection you could go with the Dkubus Franken-CIS pluf & play Kit to control both spark and fuel with custom mapping via laptop tuning to retain most of the factory components.

The Australian produced compact "Raptor" centrifugal supercharger would be ideal for these engines as so easy to adapt and Tim in QLD is a great guy to deal with when helping with adapter brackets - he has made them for all sorts of engines as per his website (sub-folder "gallery") and his are "state of the art" product with precision machining/design for flawless performance and longevity.
http://raptorsc.com.au
Liquid cooled option so no need for a front mount inter-cooler if you can't be bothered with all the piping etc

If going turbo boost - then you are up for major cost in header work/plumbing etc etc and requires ECU/tune etc
But Hendrik at Elbe Engineering in Estonia is all over the M116/M117 for bolt on kits complete with custom tune via his ECU
He provides a supercharger kit/single or twin turbo kit with all the tuning complete.
http://elbe.ee
87 White Euro 500SEC "ECE" 195kw
88 Black Euro 560SEC 220kw
89 Midnight Blue Euro 560SEL hydro 220kw AMG Kitted
http://www.flickr.com/photos/krh2013/sets/72157632548663623/
https://www.flickr.com/photos/krh2013/albums/72157668572599252

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