Bosch Super RO 488 plugs for M103?
 

Are the plugs in my '88 W124 the correct? If not I'd like to find the correct non-resister NGK plug. Anyone know a source?

Why non resistor? I used NGK TR5 which came out to $2 each.
http://www.ngksparkplugs.com/part_finder/car_truck_suv/results.asp?engineid=30015

I've read that the M103 was designed to use non-resistor plug but it seems no one stocks them anymore. I've always been very pleased with NGK plugs.

BP5EFS or BP6EFS for slightly cooler plug (highway driving). Until recently, I heard that Fastlane Phil stocked them. That may no longer be the case. Also, the MB Classic Center in Irvine apparently stocks the correct NGK plugs, and I can still get the correct Bosch H9DC0 at my local MB dealer. HTH

This info is from the archives so may or may not be correct. M103 originally
has non resister wire but had a resistor in each plug connector and non-resistor plugs.
At some point the big thinks decided to use resistor plugs and non resistor plug connectors and non resistor wire. So the answer to your question might be decided by what wire set you have. If what I said is not correct I would like to know what is correct.

This makes sense. AFIK its very hard to find non resistor plugs these these days.

This might help. NGK spark plug code
http://www.sparkplugs.co.uk/graphics...symbol_key.gif
The following spark plugs are specified for the M103
TR5
TR5GP
ITR5F13
TR5IX
So find one of these without the "R" in the name and you should be good.

Denso T20EP-U or T16EP-U

The model numbers I gave in my earlier post are the correct NGK plugs for the M103 engine. As for sources, it's true that you cannot just stroll into your local auto parts store and find the correct copper core non-resistor plugs. But there are lots of M103 motors in operation still, and we're finding plugs for them. It's worth trying the places I listed earlier. In addition to those sources, I know that there are several I-net vendors in the UK that stock these plugs and can fill orders within a week.

Resistor plugs work just fine and going out of the way for non resistor plugs is pointless. You will never be able to tell the difference from the drivers point of view unless you don't have resistor in both the wire or the plug which will cause interferance. In fact considering that the vast majority of us have upgraded out stereo and probably travel with more portable electronics today than anyone could have dreamed of in 1986 (cell phone, GPS, laptop etc) you are probably better off with resistor plugs and resistor wires. If you are going to use NON resistor plugs you need to make sure you still have resistorized spark plug wires like the factory originals. The vast majority of replacement wire sets don't have resistors.
cheers
Justin

The Bosch and Beru wire replacement sets have resistance built in. I wouldn't dream of buying aftermarket wiring sets for this car.

Get resistor plugs and non resistor wires. Whats the big deal? Having both resistor plugs and wires isn't going to hurt anything.

There has been a large amount of debating on this topic. I dont think its too much effort to find non-resistor spark plugs. I just bought a set of BP5ES's for my m116 and it wasnt all that expensive. $1.20 or so per I believe

******** has the T20EP-U's that I have in my m103 for $1.40 each....

The M103 when new and still now will perform at it's best when using the specified OEM or equal parts.

How do I know?

My M103 was purchased new, still own it, but now has the benefit of a period TurboTechnics twin turbo install.

What plugs do I run in my TT...?
NGK BP6EFS...
Easy to find?
All day long at around $2.00 each...;)

Ed A

Where to find? ******** has 'em but shipped from the UK. Anywhere in US?

?? You're looking for something closer than the several suggestions already made, including the ******** you yourself mentioned? Maybe, like your next door neighbor?

Very funny. I've looked and found no US sources. Why pay int'l shipping? Don't be a dick.

Yes, I'm sure technology hasn't advanced at all in the last 25 years and the mid 1980s was the peak of human evolution. Long live reaganomics and leg warmers

This message was posted from my AppleII
http://www.allaboutapple.com/museo/p...oni/apple2.jpg
:D

Sure technology has advanced, but a 300E is still a 300E, no different then the Apple II pic you post.
How easy is it to install a touch pad screen on this item...
Just buy an I-pad...

Same for the 300E...one owns it because you appreciate the period engineeering...
The M103-12V can be made to go very fast and handle extremely well using period aftermarket performance parts.
Power output without internal work can equal the 6.0L-32V Hammer V8.


If you own junk, it will be junk, no matter what you do ! ;)

Phil @ Peachparts still can get the non-resistor plugs. I put them in today, sharper throttle response.

Which plugs are you looking for in the US specifically?

6x T20EPU's shipped to me for $11.29
http://www.********.com/catalog/raframecatalog.php?catalog=14&partnum=5031&a=FR14-5031-356

Additionally you wouldnt try to cramp a Intel Core i7 into that Apple II would you?

Use the correct part for your car and it will love you long time.

Why the hell not?
http://cache.gawker.com/assets/image...197aeea52b.jpg
http://gizmodo.com/5159104/mac-mini-inside-an-apple-disk-ii-case
:P

It sounds like most people on here have no clue what the resistor does. It is completely irrelevant if the resistor is in the plug or wires or both. Just make sure at least 1 of the components has one.

M.B. spent vast amounts of development dollars on their engines. I'm sure they know what they are doing with the specified components.

Not only do the leads have a 1Kohm resistance in the plug ends, the distributor cap also has resistance built in.

The original idea for have resistance in the leads was for suppression of interference for the vehicle electronic components - the ECU, OVP, FPR and even the radio. The EZL is a very delicate component that can be damaged just by losing the thermal paste holding it down to the fender.

M103 engines are getting over twenty years old. We see all sorts of posts in threads complaining about idling problems and performance problems for M103 engines. The plugs are part of the problems here.
M.B. have stated that resistor type plugs can be used (times have marched on - they have also specified plastic oil can be used, it was never available back in the days when the engine was designed).
Do not put wire only non resistive leads on the engine. If you can't source non resistor type NGK's just put resistor type in - leave the leads alone. Only use OEM or Beru leads, distributor cap and rotor.

Note that platinum, multi posted plugs and other exotic plugs have been known to cause idling problems in M103 engines (over time). Ordinary $1.50 NGK non resistance plugs should last a very long time. Putting $15.00 plugs into an engine that doesn't require it is a waste of money especially when they start playing up after a relatively short life.

Everyone knows that computers are fickle machines that require nice environments to keep optimal operation going. Laptops only lasts a few years because of the wear and tear and knocks they get. Normal computers are subject to the vagaries of power flucuatuions and spikes - that's why we have power filters, surge suppressors and U.P.S's.

Modern cars are computer controlled gadgets. Vehicle E.C.U.'s are subject to all sorts of weather conditions and to the vagaries of alternators, regulators and uneven power supply. There are many filters and associated electronic circuitry the manufacturers install in the vehicles to protect the E.C.U.s and other electronic control equipment.

Well..not that you wouldnt want to buy you couldnt, as the apple ii wouldnt be able to interface with it and thus you would have wasted money on it.

Resistance is very important in electrical circuits. more of it is not a good idea especially in the case of the ignition system. The system was designed with a known value of resistance..adding to that would effect overall performance and longevity of all parts concerned.

On the topic of the platinum/irridium/etc types. My mechanic says they never ran well in these older cars. I'd never use them.

Very simple... Ohms law.... V = I x R (Voltage = Amps x Resistance)...

If voltage stays the same and you increase resistance in a circuit, amperage goes down. Less power and more stain on said electrical components to accomplish same result. If voltage stays the same and you decrease resistance in a circuit, amperage goes up. More power and more heat / strain on said electrical components.

Why screw with initial design that works when the correct parts are readily available and not too expensive. Just like putting 87 in a car that requires 91 just to save yourself approx $4.00 for a full tank fill up!

Has anyone even looked at an oscilloscope pattern of the different plugs and what it does to the coil and EZL when you have too much resistance in a circuit.

Well I'll be sure to post up here when the the devil's own concoction of resistor NKGs and 87 octane finally leaves me on the side of the road. Going an 170k miles and counting. Don't hold your breath.

Well said Ivanerrol. Too bad some folks here are always on "transmit" mode and so won't take the opportunity to learn anything. But then, these are the same ones who know better than the MB engineers how to make an MB run right, so there's little chance they'll be listening to anyone else either.

I got the Bosch H9DC0 from Peachparts special order. Phil has always given me good service. ******** has the NGKs but shipped from the UK. I didn't think of getting the Denso brand, slipped my mind. Sounds like it would have been cheaper. Next time, thanks.

Source for Beru: http://www.beruparts.com/main.sc

I heard the F8DC4 works from some people, but others say it is not as it uses a different seat or something? :confused:

Can anybody here actually confirm 100% it is compatible? They sell them on amazon for $1.65/each. Dirt cheap and they are non-resistor copper core. Exactly what we need.