Do I need to upgrade my spark plug wires - '72 250?
 

I have a Crane installed on my 250 with the Fireball coil and have no problems with it - NGK plugs gapped to .042". I am looking to replace the wires and was wondering if the standard Bosch wires would be fine, or should I look for something else? If so, any recommendations?

ryan

Use the standard Bosch wires and also use Bosch non-resistor type spark plugs. Bosch plugs are much better then NGK's.

NGK BP5ES plugs are the equivalent to Bosch's W7DC and should work fine.

In this car ('72 250), I've had better luck with the NGK plugs. I was just making sure that the Bosch plug wires could handle the 'beefed up' ignition coil...

I use the NGK's and they are fine, plug wires should be fine as well

Your original wires are/were a solid core wire with a resistor added to the spark plug end. These wires are superior to the cheaper fiber core resistance types being pushed off on us now by makers, like Bosch. If your original wires are not cracked and the original resistors are still intact I'd keep them and not worry about their ability to handle the Crane. As an alternative, you could get replacement resistors ends and some solid core wire from a good parts house and make up a set. Also, go with the NGKs...Bosch has dropped their non-resistor plugs from the catalog.

230/8

Actually, my current wires are Bosch replacements from several years ago. I was concerned about their quality when I installed them, but went ahead...

What about Kingsborne wires? I bought a set of these for my 560SL and they seem to be high quality - but I don't know if they are solid core or not?? I'm not positive the Bosch ones I currently have are either though...The Kingsborne for my 250 are quite a bit more - $62.00, I think.

ryan

Don't know anything about that brand. This outfit seems to have a good website and info if you are interested to know more.

Website:

http://www.magnecor.com/

Catalog:

http://www.magnecor.com/magnecor1/files/catalog.pdf

I did note in their catalog they indicate their wires are designed for high output systems like the Crane.

Haven't used their products so you might ask this forum sponsor for OEM product information if you have doubts about what to use.

230/8

Some night after dark and in a dark place, watch the wires with the engine running. Use "averted vision" which means don't look directly at the wires but just to one side. If you see a slight glow or small sparkles, think about new wires. If not, you are OK. Do make sure that the wire is properly seated into the sparkplug end. On my 250C, they were threaded in and tended to come out.

Michael

perfect reply "250 Coupe" I used to be able to see the "purple glow" on the Raja clips of the old days.

Now another one or two,
I wash the motor and see if it starts, "the water test" or hold the underside of your arm parallel to, but not touching, leakers will raise the fine hair, "the feely test"