Eric, hey, I have no problem being proved wrong! :D But while 750 ohms may indeed provide 6° of retard, I strongly believe that infinite resistance (resistor removed) does not provide zero retard (i.e., max power). So what I'd like to know is, what resistance value is needed to pick up those elusive six degrees?

The problem is I don't have the ETs yet to prove my point so I just let it lay.
As far as the info goes I think it is here: http://www.peachparts.com/shopforum/mercedes-benz-performance-paddock/32224-read-free-hp-w201-w124-owners-pictures.html Just be sure to not skip anything and read everything on every link (yeah, it's gonna take a while but I think the info you want is in there somewhere).
Oops, I just realized that this is the thread you refer to as a "steaming pile of..." but somewhere in there is a post or a link from a guy that shows the actual number of degrees of advance and at what RPM the M-103 receives that advance with and with-out the 24 81 resistor. Regards

Happy to think it's false, but I believe I have some proof... here http://www.hamsk.ru/murzik/KE-jetronic/WIS%20Test%20data%20KE.pdf
bottom section of page 3

or http://www.hamsk.ru/murzik/KE-jetronic/EZL.pdf middle of page 3

but it isn't totally conclusive. To cloud measures the second link appears to have a translation issue and has a W instead of an ohms symbol but those W readings coincide with my own resistance measurements for this trimming plug, apart from position A -1W I believe this should be an infinity symbol as infinite resistance is what is found on my car's plug at that position (and 1 ohm seems very unlikely given the 0 ohm reading at the opposite G position of the scale...

i'd like to chip in ~~~ eliminating the resistor definitely made a difference in mine, no more cold off idle flat spot and more responsive acceleration

as an old hot rodder and playing with timing from the 50's to the 80's. i've watched the timing go from @10 degrees advanced to 0 to @7.5 retarded, mainly to pass emissions. total timing ranged @28 to 32 but could be pushed to 36-40, but this was done on a mechanical distributor with springs. needless to say they always run a bit better with an advance bump

anyone know the total advance spec on the m103?

if 0 is all you can get by eliminating the resistor, can you get another 5 or 10 by playing with the top dead center sensor or the repositioning of the cam gear?? and would this affect total timing, as controlled by the brain ??

Ah, now that is interesting. Note that in the first link, it is the non-catalyst version where infinite resistance (no resistor) translates into full advance (zero retard). But for the catalyst (KAT) version, full advance requires a 750 ohm resistor!

For an English version of the second PDF, click here. Unfortunately that document doesn't specify what each of the 7 position does, it just says what resistance should be used, and the values for the standard setting.

It also appears that things could have changed around the 1988/1989 model year, which may explain why my 1986 300E lost power & economy with the resistor removed, while other people (presumably with newer models) experienced a power gain.

:confused:

My 88 and 89 love the mod. There was another change starting with the 90MY and it seems there are a number of those guys that aren't as excited about the mod either.

Pulling the resistor advances the timing 6 degree as the 750 ohm resistor is what creates the 6 degree retard.
I want more timing on my TT as my AFR averages 12.8 and under full boost it's 11.8:1
Seven pounds and I dyno'd 302 torque at the rear wheels on a load dyno.


This is from my M103 engine manual..
Pull the resistor and read the timing and you'll end up with six more degrees advance...

http://i19.photobucket.com/albums/b1...scan0001-3.gif

I thought the V-12 came out in 92.
Yes it is. Yes it does.
No. The CIS-E makes good power and torque it just can't match the good emissions and fuel economy of a good sequential FI system.

Sorry to hear about this but I believe you can't keep a good car down and you can't keep a good man down. You'll bring her back. Regards, Eric

Everyone, see updated post #52 above. Eric

"LET'S START AT THE BEGINNING !"

"Published ratings for 1988 300CE M103-12V are 177HP / 188 Torque."

"Baseline dyno done on 3/30/2007 was 136HP / 145 torque.
Pulls were made on a Mustang load dyno which indicates about 18% lower then an inertia dyno."

"Drive train loss = 30%."

"Turbotechnics kit installed with only mod being the application of a Split Second stand alone controller to fire the two additional injectors.
KE-Jetronic and fuel delivery system remains stock."

"5/24/2007 dyno pull 196HP / 221 Torque."

"After I got the car back I replaced the supplied intake and boost coil hoses with silicon and aluminum tube.
The supplied Fram panel filter was replaced with a K&N filter.
The R16 resistor removed to pull about 6 degrees advance."

"Today I put it back on a Mustang load dyno to see what my mods produced."

"1/17/2009 219HP / 254 Torque."

"The AFR was great under boost at 11.9 under full boost.
What was noticed was that the boost was only at 6.2 max with an average of 5.4"

"So about two turns on the wastegate linkage on the Garrett T2's and..."

"261HP / 302 Torque"

"This is at the rear wheels.
Max boost now 7.3 with a 6.9 average.
Add back the 30% drive train loss and it's at 340HP / 393 Torque."

"Torque is significant...back end goes out with any hard throttle on the 2-3 shift !!!"


The above is RBYCC's documented proof that the removal of that Knappy resistor even helps his boosted car. He said: "The R16 resistor removed to pull about 6 degrees advance." But if you read the whole thread it's clear he meant to say: "...to add 6 degrees of advance"
The whole thread is here: http://www.peachparts.com/shopforum/mercedes-benz-performance-paddock/242911-300ce-turbotechnics-dyno-revisit.html (I know most of you already know about it). Regards, Eric

CIS guys like bigger wheels too! Remember, I'm a CIS guy too! We aren't going to get to far off topic I promise. I just want to know real quick where I can get those special bolts and the other thing is I'm still not clear if you think these 16 inch W-140 wheels are OK for a W-124 or not. I really like them cuz 1) I already have half a set, 2)They look just like my stock 15s so I can maintain the sleeper look and 3)They are super cheap. Thanks G-man!

It's not too OT ;)

Has anyone played with the correction plug, in my case it's the one with ECE written on it back by the ECU and with tamper-proof wire on it?

This was my post to another forum:
interesting..ish

Thank you pentoman, u have no idea what help ur post is. so if i need more part thort fuel i stick it to 2????

Well first you want to check the part number on your switch is 014 545 70 28 because that's what those values are posted for (check the link). If it's the other number (which appears to be on KAT models) then the values are different. As you assume, I assume it's changing the fuelling map or something, at certain loads/rpms/temps, but I don't know. It could be worth setting and trying it for a few days though (if you didn't have a broke piston :( ).

ya thanx mate,car is already in the shops for an engine rebuild, might go for a single turbo setup and a FMIC. still not sure abt the turbo setup, but i know that one of my turbos needs a rebuild as well.

will make up my mind this week.

ya once car is back on the road ill try it. can you email me the pdf to jayrasheed@gmail.com please. it doesn't seem to open the link you posted.

if its too much trouble just point me to another link, as its obvious i love knowing abt the cis. :P

M12 bolts with M14 ball seats can be purchased from this vendor. I think the W140 wheels are 16x7.5, with offset ET51 (I think), which may not fit at all... or it will at least be VERY close to the strut, or require spacers (which are a very bad idea). The R129 wheels will be 16x8.0, and I'm not sure about the offset on those, could be ET34 like the 500E wheels though. These will stick out too far and rub the fenders.


:zorro:

I still think the year of the car (more specifically, the part number of the EZL module) is critical as to if the "resistor mod" provides ignition advance, or ignition retard. I don't think I've seen anyone with a 1986 or 1987 300E report great results by yanking the resistor. (??)

On a side note, remember that zero ohms is not the same as infinite ohms, they are opposite. Zero ohms would require a piece of wire to short out the terminals, infinite ohms means you can remove the wire/resistor/whatever. The M103 service manual indicates zero ohms as one of the three options, but this could be a typo. (??)

:nuke:

true, but with all the docs in this thread it should be easy to fit a variable resistor to the timing side of the temp sens and try more advance. i still say it will give good hp over stock. hope some of u try it for proof.

as for my turbo setup, will be fitting my stock exhaust manifolds and custom make 2 pipes to fit on those and join in flange that fits a mitsubishi evo 8 or 9 turbo. then make all the piping need to fit a w202 c230 komp front mount intercooler.

what do you think guys???

On the world or euro cars with the adjustable resistance, every turn/notch is a three degree interval.

The added advance is mechanical only as the full vacuum advance is the same.

If you look at the charts you posted the difference between the "S" and "N" setting is six degrees.

Still not really noticeable in most cars, more noticeable in a tuned or boosted vehicle. :)

I just re-read that whole stupid thread. There is a huge amount of conflicting information. A number of people with M119 engines were claiming gains on the butt dyno, which we both know is absolutely false. At least one guy had the guts to say it had zero effect on his 400E (actually, his numbers showed a power LOSS). Also of interest is that many M103 owners had widely different results - some claiming massive power gains, others saying it did nothing at all. Post #235 has a guy who did dyno runs and proved basically zero power gain with or without the resistor. At best, on a stock engine, it may offer some part-throttle power gain.




Yeah, every list I've seen with details of the 7 positions has different resistor values, different degrees of retard, and different claimed effects. Like I said earlier, I think it varies with model & year and there is no single, master list that applies to all cars. Here's my favorite post (#219) from the "steaming pile" thread, which I suspect has the most accurate answer, direct from RENNtech. I added some bold highlight:

-----Original Message-----
From: Hartmut Feyhl
Sent: Wednesday, October 16, 2002 2:02 PM
To: 'Scott M. Shell'
Subject: RE: W124 M119 motor question


Not so easy, sorry. There are many different models and even much more different part#’s for the ignition system (EZL) and every unit works different and the resistors have a different meaning. In most cases, position # 7 is diagnostic mode, on other units it’s reversed, on other units only 3 positions work and on some units it doesn’t work at all. On those really old models where it does work it can overheat the catalytic converter and destroy it. That is the real reason why Mercedes has on cars equipped with cats a fixed resistor in every country. They were concerned for their cats, not the quality of the fuel.

M119 engines with LH or KE usually have 2400 ohm with cats and either 220 or 470 ohm without cat ( depending on control unit ). If you want to risk your cats you can try it. The difference is maybe 2 hp and not noticeable.

Hartmut

Here is some additional good reading on the same topic - I agree completely with Greg's findings in the first post (two threads, same initial post, different replies in each though):

http://www.peachparts.com/shopforum/mercedes-benz-performance-paddock/67773-read-if-you-have-done-free-horsepower-upgrade.html
http://www.peachparts.com/shopforum/tech-help/67772-those-m102-m103-free-power-upgrade-must-read.html


:deadhorse:

Thanks for the wheel bolt link G-man!
So one of my suspicions is confirmed---We (U.S.) got the fixed resistor for emissions reasons.
The pattern I noticed is that 88 and 89 guys seemed to be the most positive about the mod. 90 and later guys not as positive. 86-87 guys in between those extremes.
Also I still believe that the majority of the gain is in low end torque and mid range torque.
Lots of stuff to digest here---will be back tonight.
Isn't this a beautiful thing though? We have a guy in the middle east, one in England, 2 on opposite ends of the U.S. and one kinda in the middle all sharing their knowledge and ideas. I know it's not that unusual in these days of the world wide web but I still can't help but feel lifted by it all. Gives me hope for humanity. (G-man, I don't know where you get all those cool icons but this is a good place to insert one of those group hugs---I just love those group hugs!) Regards

gsxr. So thats where u been the last few hours.:) ya man messing around with the plug wont make any real diff. I moved this switch to inside my car to have control over retard or advance over the timing. But only cause i was fooling the temp sensor to get more advance which lead to some ping in very hot ambient temps. Also when ever i used high oct fuel i used to pull more timing thru it.

As for the injection side, i used to enrich it also by fooling the temp sensor. But i only used high resistor values for when i mixed alcohol in my tank, as this would cause the car to lean out.

I had a friend who didnt believe that the timing trick works untill i raced his c320 against my car with and with out the temp trick.

Any way as u say each ezl seems to respond differently. But i am sure a try will help.

Guys, I think the temp sensor trick has much more potential for real, measureable power gains. Eric basically proved this already, and I plan to verify it on my cars by the end of April (it's still snowing around here, so my cars are hibernating). The ignition mod appears to have far more limited effect (and is useless on M119 engines anyway).

:hat:

Jay, could you please post the resistor values you used in place of the coolant temp sensor? Thanks. Also, you have to be real careful with detonation. You do know that's what did in your piston right?
Everyone re-read post #73. I've added to it. Regards.

Eric, yup u got to love this day and age. Most me my posts are done from my phone even.:) some times just too lazy to use the laptop.

i kept the temp sensor in place. I just cut its feed lines going to the ezl and the injection ecu and reconnected with variable resistors.

Started with abt 780 ohm for timing and some 400ohm on the injection (iirc as those where the values i used back in 2000). My ezl switch was set to 1. Then i tried 1.5 Kohm for the timing, worked best for summer time with the ezl on setting 7 and in winter on S or 1 depending on the ambient temp.

Yes i know abt ping and tomorrow ill know what gave in my engine.
Dont forget my engine had over 230Kmiles on it, so it could have just called it a day.:)
Any way if u hear some ping dont be scared. Just dial it down a bit. On many many occasions i ran my car with some ping when it was still N/A due to lack of high oct fuel.

In n /a its unlikely that slight ping will do any damage. Still if u hear it just ease down the values cause if ur head gasket is old prolonged knocking will make it give.

Some factory docs out of the WIS which may help answer some of the EZL trim plug questions (these are PDF files) :

Trim plug function

Ignition timing adaptation

Note that the resistance for each position (1-7) is always the same, but the "N" and "S" designators may change to different numbers depending on the version (KAT, non-KAT, auto trans, manual trans, etc). There still is no simple document showing which position offers which timing change, probably because - as Hartmut said - it's different for each EZL/engine!

Also of interest is the information I found in the Engine Diagnostic Manual Vol. 1... this also shows how the resistances are different for each (USA) engine, and can vary by model year:

Engine 102.985, 09/88 to 08/89 - resistor is 750 ohms, zero timing retard
Engine 103.94x - resistor is 750 ohms, zero timing retard
Engine 103.98x - resistor is 750 ohms, -6° timing retard
Engine 104.98x - resistor is 2400 ohms, zero timing retard
Engine 116.965 - resistor is 750 ohms, -6° timing retard
Engine 119.960 - resistor is 2400 ohms, zero timing retard

There is this comment after each reference resistor spec in the manual:

Note: If the reference resistor is missing, the ignition is retarded 3° at wide open throttle.

Finally, I found this gem, note that it shows this applies from model year 1988-up (which may explain why there was a loss of power & economy on my 1986 model 300E):

EZL trim plug positions, M103.98x


:euro:

The key is to establish your existing timing before you remove the resistor.
Some cars pull more advance from the EZL as stock then others.
Notice in the charts that you posted the timing range of several degrees.
Removing the resistor in this case gives no improvement.
The increase, if any, from the removal is only up to 2500 RPM.
It's a low end acceleration thing.

The EZL has 3D maps stored in it that are activated by the resistor value.
Much of the variable comes from engine load via the vacuum line.

Lot's of info to digest--- (burp)--- still digesting. I'm gonna have to get my 2 M-103 cars to the track and do some A-B-C testing. "A"= 24 81 resistor in place, "B"= resistor removed. Do you guys think it will be safe to run a jumper wire in place of the 24 81 resistor for test "C"? The 88 was made in the fall of 87 and the 89 was made in the fall of 88 btw.
I need to get the 88 running again first: http://www.peachparts.com/shopforum/tech-help/244582-88-300e-m-103-auto-turns-over-wont-start.html
My 89 also has over 230,000 miles on it---I hope it's not getting ready to "call it a day". Regards

What month was your 88 M-103 car made? Is it a stick or auto? Do the sticks have different EZL numbers? Just trying to eliminate variables. Regards

I dont think you have anything to worry abt, my car ran most of it life on full timing advance, revved beyond its red line on every possible occasion. Has done long motorway cross country runs, add to that experimenting with strange fuel mixes. then in the end it was turbocharged and run lean for some time. then it pinged on constant basis prior the alcohol injection kit.

i really think those engines are so well built that you can get away with almost anything done to them.

i did cover some 15000 miles with the turbo kit installed, and the engine didn’t pack in completely, it started to have some blow-by which indicated weak rings or a cooked piston. So I thought a rebuild while its still recoverable was due.

"...revved beyond its red line on every possible occasion." I just love that---another delinquent like me. Regards

:P i did increase the rev limit from the std 6440 rpms to 7k. To do that i removed the fuel relay, this also removes the hard rev limit which cuts fuel supply to control the engine speed.

Then there is another rev limiter a soft one in the injection ecu this activates at abt 6600rpms, to fool this you can tap into pin 25 ircc and install an rpm window switch or some circut custom made to generate some load on the line. This for some reason stops this limiter from being activated.

Now your left with the last limiter located in the EZL unit. this one is also a soft one that activates at 7000RPMs. you cant remove this but from what i heard you can try an EZL from the V8 M117 560 engine, THIS UNIT I THINK HAS NO REV LIMIT IN IT. but wouldn't recommend it since it prolly has different timing maps and the stock cams of the M103 aren’t worth anything over 6600 HP wise.

on open free flow mufflers the soft limiter at 7K just sounds sweet.

Are you talking about the fuel pump relay behind the battery? I thought if you remove that the car won't run. I'm trying to score one from a same era M-104 cause they have a 7,000RPM limiter (I think) but the other changes that occurred to all W-124 eng. management systems in 90 might make such a swap incompatible. Regards

Ya if you remove it it wont start. but i replaced it with a normal bosch relay, i will get you schematic of how its connected so as to have the pumps start only with the key turned to ignition.

mind you, you will lose the cold start function. as that is also controlled by the relay. i also think you will lose rpm read out on the diagnostic socket.

What about a swap to a 90 MY year M-104 relay? (Remember, my 2 M-103s are 88 and 89) (I was amending my previous post while you were posting a new one---see above. It happens a lot with me cuz I'm so slow at typing.) Regards

Eric, i dunno if it will work, u need to ask on the forum. i know alot abt those cars but still.

but if your M103 is yr 88 it should read 6550 rpm on the fuel relay. i saw dont go to 7000, it will hurt your acceleration more than make it any faster.

and its a sure way to do your rings in if the engine has lots of miles under it.


if you still want to hit 7000rpm, make sure you retard the camshaft some 4 deg to shift your power to that range.

I know that for sure, my car dropped from 0-100mph in 21+ sec to geting the run done in just under 18 sec, with no trick fuel being used ( adding alcohol into the tank and running more timing advance and more enrichment). and car did the 0-60 mph run in 7.2 to 7.4 secs every time.

Here is a pic of where i placed the R16 switch:
Attachment 65179

here well the car looked sweet in this pic so y not post it :P:

Attachment 65180

Eric

Automatic....
I bought it new off the showroom floor in May of 1988.
Without looking it up, production was probably very late 1987 to early 1988.

The variable would be what your existing timing is with the R16 installed.
Timing varies from car to car.

Jim Villiers MBCA Virginia Beach had a supercharged W201.
Many years ago he pulled the R16 and showed about a one second improvement to sixty.
The timing pull of even six degrees seems to give tremendous gains with boost !

Ed

Jay

Food for thought ?

http://forums.fourtitude.com/zerothread?cmd=print&id=3267302

thanks Ed,
i happen to have seen that thread before. its a nice way of keeping things stock till you really need the enrichment.

one side not is that the true benefit of enriching is the sweeter response on part throt.

by the way, when fooling the temp sensor for both timing and fuel, the M 103 generates a lovely deep tone which gives this engine a sharper edge, and the throttle response is snappier

I started searching for the " Holy Grail " on VW, Ferrari, Audi, Porsche who all used CIS-E...

There is no real answer due to the split ignition and fuel control...

on my turbo setup what i really need is a way to enrich below the 4000rpm range. i am activating the full throttle function, and while that helps its far from enough!!!!

any know how to solve this? maybe play with the air mass plate output?

there's a thread on here or BW about a guy who bored and sleeved a m103 throttle body (65mm) and fit a 400e (70mm) plate ~~~ don't think he's tried it yet

Love that headlight panel mod---I've done it too.

Next time you are near the car, could you please take a peak at the build date on the build plate on the D.S. "B" pillar? I'm just really curious how close it is to my 88's build date. Also, has your EZL unit ever been replaced? If yes, were you able to get the same part number? Regards

I'm writing myself a note...
It's a coupe so no "B"
Serial#710441 ( last part of VIN )
Amazing how you forget stuff when you get old !!!

EZL is as delivered, never had much replaced over the twenty one years of ownership.

Around 67K miles from new, TT installed at 62K miles.

Remember, I have an 88 and an 89. Actually don't intend to rev to 7000RPM. I just want a little more wiggle room. Don't forget, these relays also control the WOT shift point and I have found a large difference in both stock and aftermarket relays. WOT shifts from anywhere from 5000-6700RPM with just a change of the relay. Even Car and Driver in 4/87 noted how their M-103 powered 190E exceeded the redline in both 2nd and 3rd. They said this was "Very un-Mercedes like". Their car saw 6800 RPM in 2nd! Even though 6500 RPM is well past the power peak, it helps acceleration to be at or above the torque peak when you hit the next gear which in this case is 4400 RPM (3.0) or 4600 RPM (2.6). That means winding it to about 6500 RPM. It is especially important if you have a post 9/88 trans. (which my 89 has) because the spread between 1st and 2nd is greater. (3.87 and 2.25 vs 3.68 and 2.41 for the pre 9/88 trans) Regards