Plugs and wires

jcc911 · 04-01-2004, 09:01 PM

Guys,
In a few days I will be doing a "tune up" on my 78SC with the addition of SSI's and Dual/dual muffler.
Now, I believe I have everything but the wires. Any suggestions?
Also I bought Bosch Platinum plugs, but now after reading past posts, people are strongly suggesting not to go down the platinum route.
So my questions are?
1. What ignition wires should I buy? Any particualr size (is 8.5mm better than 8 or vise versa)?

2. Should I not use platinum plugs and why?

Thanks
Jeremy

Pettybird · Pettybird's Garage

I bought Magnecor wires at a swap meet for $100. Somehow, it felt goot to pay a little more than $15 per wire than the factory $20 per wire set. And red looks nice.

WTF? I can buy resto correct, date coded, licensed wires for the Superbirds for $40, and I even get two more wires. Summit Racing sells an Accel set of braided wires, you cut 'em, for $45.

How much German voodoo can there possibly be in a set of wires???

-Doug

keithdog72 · 04-01-2004, 09:47 PM

I have also heard that you shoudn't use platinum plugs. Could someone please clarify why this is??? We need reasons

Steve W · Steve W's Garage

Platinum plugs work well on water cooled and newer vehicles with tight emissions controlled air fuel ratios. The advantage is they last longer because the platinum electrode does not wear out as fast as a standard plug. The disadvantage is platinum plugs don't have as wide a heat range as the spec'd Bosch or NGK copper plug. 911 air cooled motors with the wide temp ranges we run in, and the large variations in air fuel ratios and varying degrees of oil consumption, have an effect on fouling the plugs, causing misfires and/or incomplete combustion. The copper plugs have a wider heat range, so can burn off more of the residue over a greater temp range than the narrower window of a platinum plug. Keeping the plugs clean is key to consistent complete combustion and crisper response, which is why sometimes aftermarket systems such as MSDs contribute to better performance, such as with carbed performance motors.

jcc911 · 04-02-2004, 04:18 AM

Thanks for the info Steve.

IROC · IROC's Garage

For wires, if you don't want to spend the money for Magnecors, you can also use the factory wire sets used on the earlier cars. They are non-shielded (don't need it anyway) and have the correct factory Beru plugs at the ends (which is probably what you're really paying for).

Last time I bought a set of these they ran around $70-$80.

Mike

Superman · 04-02-2004, 05:31 AM

I have had plenty of bad experiences putting aftermarket parts on German cars. One example is when I had the bright idea of tossing the factory ignition wires from my '84 Rabbit in favor of a new set from my local autoparts store. Few weeks/months later the engine started missing on 1 or 2 cylinders. Ran like *****. turns out that the hot ignition system fried the aftermarket wires. A new factory set was spendy, but I learned a lesson. Again, German cars can tolerate aftermarket parts sometimes, but often they will NOT. The original German parts are bigoted, apparently, because they gang up on the (Mexican, Taiwanese, whatever) foreign intruder until it is removed. Kinda like my Labor friends and their pickets/boycotts.

A set of "early" 911 wires would work just fine, and I'd recommend them before any aftermarket ones, including the famed Magnacore units. Case in point: We have all heard of frustrations with aftermarket CD boxes. Permatune and MSD are the most favored, but neither are reliable. It seems clear that the best and most reliable CD box you can have on your car is........yep, you guessed it. Bosch OEM.

dhoward · dhoward's Garage

Build your own out of a set of Accels or MSDs.

It's not clear to me that a Bosch is better than an MSD, and I have not personally had reliability issues with them in either automotive or harsher marine environments. Proper installation is key to any use of aftermarket parts.

mudman · 04-02-2004, 05:49 AM

I don't mean to steal your post but... Looking for wires for my 73.5T and I see magnecor for about $120, oem w/braided ground for $210, and my brother suggests Jacobs w/braided ground. Any input?
-Jeremy

IROC · IROC's Garage

Quote:

Originally posted by mudman
I don't mean to steal your post but... Looking for wires for my 73.5T and I see magnecor for about $120, oem w/braided ground for $210, and my brother suggests Jacobs w/braided ground. Any input?
-Jeremy

Yeah - don't buy the braided wires unless you're looking for concours points. They are a waste of money. Early, non-braided factory wires are the way to go.

Mike

mudman · 04-02-2004, 07:19 AM

But what is the reason they were braided in the first place, Radio noise?

tsuter · 04-02-2004, 07:41 AM

Is there a problem with the existing wires? Or is this just a "feel good" change?? OEMs last a long long time.

1fastredsc · 04-02-2004, 07:48 AM

I believe they are braided to to prevent arching, sort of like a grounding shield.
I've also been told that one main reason to use platinum plugs is that at a certain temperature they become a self cleaning metal, which is why they last so long. But the downfall, besides heat range, is that platinum is not as good of an electrical conductor as copper.

mudman · 04-02-2004, 08:04 AM

My wires look like crap, I'm missing the plug hole plugs, and I suspect they are original (30 yrs), and I want to do everything I can to ensure a smooth running engine.
-Jeremy

Oh yeah, the engine has been sitting on a pallet for about 4 years

Early_S_Man · 08:52 AM

Are all of you guys that just throw away your OEM wire sets NOT AWARE that the ends unscrew and the wire itself can be replaced with bulk spark plug cable???

Here is a thread detailing the successful rebuild process:

Ignition Wires

Countless numbers of owners and pros have done this for decades with just as good results as spending $100+ on Magnecores or other aftermarket JUNK!

The air seals can be replaced with VW part[air-cooled Beetle] from an aftermarket VW supplier or foreign car supply. VW only sells an 'A' suffix version that won't work on 911 valve covers! Your air seals should be checked every time you change the oil!!!

mudman · 04-02-2004, 08:49 AM

I, for one, did not know that. Thank you very much!
-Jeremy

techweenie · techweenie's Garage

Warren makes a good point, especially since the weakest part of any 911 spark plug wire set is the connection to the spark plug. Factory Beru connectors have a spring wire that gives a positive 'snap' in place, while most aftermarket connectors use metal tabs that barely hold on.

Argeo · 04-02-2004, 10:43 AM

Alright, you guys get me thinking about my wires. They look like the original wires on my 77 3.0. I also have a Permatune (came with car). What do you guys recommend? Sorry, just looking for a quick answer.

Thanks,

David

jcc911 · 04-02-2004, 10:44 AM

Suter,
I do not think there is anything wrong with the wires. I just wanted to replace for an ease of mind. I just assumed to do it as a part of the tune up. The car has 78K, but I have maintainence records of everything but a tune up, which is a little odd.
Thanks for the info.

(Thad, how many of us on this board are in the WI, or Milwaukee area? Are you out by Madison?)

Ian Comerford · Ian Comerford's Garage

The wires on my 79 SC were breaking down and I ordered a set of pattern ones, what a waste of time! They were very awkward to fit, didn't snap positively into place and left me firing on 4 cylinders. The other downside was that there was no moulded on cable clamps, so it looked a real mess. In short I wasn't happy. I sent them back and ordered a set of oem wires, paying a fairly hefty sum. But they fitted perfectly, clamped down very tidily and because the old set were almost certainly original and had lasted 24 years I figured it wasn't bad value.