RE. POST: READ!!! Free HP for W201 & W124 owners!
 

I searched my 88' 2.3 for the resister in electrical tape but could not find it. Could somebody please view the photos below and let me know if you see this resister?

This is a resister that might increase power by either removing it or change the resistance vaule. The orginal post is located at with the title...READ!!! Free HP for W201 & W124 owners!\

The photos of my car are located at the url below, double click the small thumbnails to view a larger photos. I would really appreciate any help.


http://machnumber2.50megs.com/photos/benz3/benz.html

Machnumber2

You kidding right?

I found mine via (picture #1) towards the back of the engine, above, between the valve cover and the intake manifold. If I get a chance tomorrow I take a picture and post it.

Haasman

That would be great if you could take a photos of it, what type of benz do you have? Did you say that you found mine in photos number 1?

There are two resistors on my 190E. I can't tell you why.

Here are their locations, each coming right out of a wiring loom.

Haasman

not every car has this
 

Be weary that not every car has this, it depends on what type of ignition your car has, mine does not have this resistor.

I'm not sure, but if someone can back me up on this, I think an easy way to tell if you have this resistor or not is by looking at your igitnion module, if there is only two connectors on it, you have what I have and you don't have the resistor, if you have four and a vacuum line, then you have it.

Other memebers also mentioned that this is not as good as it sounds, and not worth the gas money in the long run, I prefer to make sure that engine is well maintained instead.

xp

Don't expect any measurable performance inprovement with the removal of this resistance.
You'll probably get 3/64 mouse/power at part throtle between 1,200 and 2,500RPM. That is all.
This resistance decreases the distributor timing at partial throtle at low RPM. to reduce detonation.
it does nothing at higher RPM or past half throtle.
JackD

Thanks for the reply's. I was not able to find the part I was looking for though.

I located the resistor on my '88 201/2.6 on the inside side panel of the battery compartment. It's a tapped up pigtail tie wrapped to a slot on the panel. My understanding is that plug in resistors are used to vary the timing on EZL ignitions that have the non-adjustable TDC sensor. My former '84 2.3 had a conventional adjustable distributor, but I'm not sure about the later 2.3s.

The original post has a link to another post that lists the resistance values and timing changes. No resistor means full advance, the US resistor is 6 degrees retard, and zero resistance (plug shorted) is 12 degrees retard.

I e-mailed the original poster and asked if he checked for any change in base timing. He did not, but reported better low end torque. I want to retard by initial timing to give me more margin on emission testing. My HC is at the ragged edge of the limit, but I don't have to be tested for another two years, so I don't plan on changing it until them.

If anyone does remove the resistor can you let us know if it changes the base timing. For my '88 it is 9 degrees and is always listed on the emission label. Different years might vary, but check the base timing before you remove the resistor and then again to see if it changes.

Let us know what happens.

Duke

Measured improvement or imaginary?
 

A few years ago (before I discovered these forums) I experimented with the ignition timing on our '90 300TE (3.0 M103) by way of changing resistor values. In fact, I made up a multi-position switch box with every value resistor listed in the workshop manual.

In Australia, our car only came with a 220 ohm resistor from memory (despite the owners manual showing the multi-position selector as fitted in Europe). This resistor was presumably to suit our relatively low octane regular unleaded fuel (92 RON). I was prepared to make exclusive use of higher (95 or 98 RON) octane fuel if by changing the resistor value improved power output and possibly fuel economy. Initially I tried no resistor (supposedly for maximum advance) and could feel no change. I then tried different resistor values and got varying results. This made me decide to use a measured approach by actually checking the ignition timing. The first observation I made was that the resistor only affects the full load timing (ie. minimum vacuum). At part throttle it makes no difference what resistor is used. The second and more startling observation was that only two resistance values caused anything other than maximum retard, the original 220 ohms and 750 ohms from memory. Higher values or no resistor caused maximum retard and a theoretical loss of performance. Fueling with 92 RON confirmed that only the 750 ohm resistor gave enough advance to cause any pinging.

Are we often imagining an improvement because we believe there should be one without actually measuring it? Don't assume that a higher value or no resistor will give greater advance, measure it. Also, anyone who claims a change at light loads or small throttle openings is imagining it. The difference between the original resistor and the only other value that gave a change in the right direction on our car is very slight and only at full throttle.

I did however, eventually decide on a setup with a small 2-position switch and just two resistors. Normally it is set to the higher value and we run 98 RON fuel. Should only 92 RON be available (eg. when travelling in the country) we have the option to switch to the lower value resistor for less ignition advance.

I have yet to perform any tests on my recently purchased 190E 2.3 to see what measured changes can be made to it by way of the ignition programming resistor.

It would be interesting to see what results anyone has obtained from this modification by way of dynamometer testing.

Greg,s comments are right on the money.
I've fiddled with this procedure or removing the fuse on my 260E (103 engine) and actually measured the total ignition advance in 1,500RPM increments with and without the fuse.
The only repeatable reasults I got was a slight ignition retard between 1,500 and 3000RPM. Below and above, absolutely no change in ignition timing.
This is why I said earlier that a 3/64 mouse/power increase at part throttle would be the expected results.
jackD