'86 Carrera Simple Ignition Question

triwave · 07-12-2004, 08:56 AM

Hi,

I've been doing some quick reading on Ignition upgrades, primarily Permatune, Jacobs and MSD units. Accross the years the ignitions differed with the use of points, CD style, coil choices, mounting locations, etc.

I'm a little confused with all the options and thus what exactly a MSD or similar replaces and how difficult the job would be.

I have an '86 Carrera (narrow body) - what system am I looking at when I peek under the cover. I see the coil (which burned up on me) mounted to studs on the fender well and then several plug in aluminum modules under the left side cover. I assume one of these is the "ignition module" itself, but it is not a CD style is it?

Appreciate any clarification you can offer so my further reading is more intelligent. Thanks.

cowtown · 07-12-2004, 09:11 AM

No, you have a DME car which doesn't use the CDI style of ignition. Others can elaborate on the Carrera ignition, but the CDI boxes are used with the CIS (74-83) cars.

Rot 911 · 07-12-2004, 09:12 AM

And your DME Box and relay are under the driver's seat.

triwave · 07-12-2004, 09:55 AM

This is what I was thinking, so is there any logical upgrade path for ignition on this system if the DME controls spark and timing information? In particular I read about multiple spark discharges for low RPM operation and higher coil voltages as RPM increases which both seemed like good things - but I'm wondering if maybe the only real upgrade for the '86 system is a new coil.

911pcars · 07-12-2004, 10:25 AM

Not much to be gained by upgrading your system.

If you don't have enough spark or spark is inconsistent, something is wrong with the basic system.

On earlier cars, the upgraded systems either replace a malfunctioning factory spark box or allow the engine to run a little smoother at idle/low speed (more of an affect in carbed or MFI engines).

Another upgrade to earlier systems (not yours) is replacing mechanical ignition points with electronic triggering for less maintenance.

Sherwood

cowtown · 10:29 AM

Is there a reason you want to upgrade the system? If nothing is broken, the DME system works very well. Change your plugs, cap and rotor when you do the coil. If they are original, the plug wires are ready to be replaced as well.

Multiple spark systems do not give you more power, they just work better with fouled plugs.

If what you're really after is more power, there are not a lot of cost effective options. A Euro premuffler and Steve Wong chip are about the best you can do without spending a lot. Good luck.

triwave · 07-12-2004, 05:13 PM

After some research and discussion I think I will proceed by replacing the coil, plug wires, plugs, cap and rotor. Sounds like taking care of these items will have my ignition in top shape.

Now the question is which wires... it's just like buying speaker wire - every manufacturer makes claims of their construction, connectors, etc. to justify charging and arm and a leg. What really works?? I'm leaning towards the KV85 from Magnecor.

stlrj · 07-12-2004, 05:29 PM

Go for the Magnecores.

Joe

triwave · 07-23-2004, 07:20 PM

I purchased a set of Magnecor wires and was going to install them in the car ... but when I look more closely at the route the ignition wires take on the right bank of cylinders it appears they are routed and held in place under the A/C compressor. I can't see how to remove and replace these wires without removing the compressor (which I don't know how to do). Is this correct or am I missing something??

stlrj · 10:58 AM

I take back my recomendation of Magnacores in favor of keeping your stock Beru ignition wires. I tried a set of Magnacores on my 86 and was not impressed. I still had the slight miss and stumble off the line that I was trying to eliminate. Instead, I reinstalled my old Beru cables, except this time I sealed each wire, spark plug and cap ends where they enter the boot, with clear silicon sealer.

Got rid of my stumble and revs all the way to redline without a miss.

I also like the looks of the stock Beru cables much better too.

Cheers,

Joe
86 3.2
HEI ignition coil
.060" spark plug gap
64 Autolites

triwave · 07-24-2004, 02:23 PM

Did you have to loosen or remove the A/C compressor to route the ignition wires?

cowtown · 07-24-2004, 02:54 PM

I don't think you should have to remove the AC compressor unless the wires are somehow routed differently from the factory setup. Normally the wires travel along the fiberglass engine shroud.

Anyway, if you do have to move the compressor, it's easy. Do not remove the pressurized lines.
1) loosen the horizontal tensioner bolt on the bottom left. This bolt makes the compressor slide from left to right to adjust belt tension. Just back it off.
2) remove the bolts holding the compressor to its mounting bracket.
3) put a towel on the right fender

Now you can pull the compressor up off its base. and sling it over the fender. It seems weird to do this, but it is SOP for valve adjustments.

CrossT · 07-24-2004, 05:05 PM

You do have to remove the AC if you want to get to the connector below it. I had no wrench that would get to it. I just cut the old wires and left the small portions under the ac unit. Figured I'd get to it later [1 1/2 years ago] . . .

Other thing with Magnecores; they don't go through the guides. They are thicker than the stock Berus. When installing mine, I had to drill the guides [just the plastic ones, not the ones on the fan housing]. It wasn't hard, just wasn't expected. Came out fine.

todd
86 coupe

triwave · 07-24-2004, 05:15 PM

Thanks for the detail Colin, this is exactly the info I was looking for. Compressor removal looked as easy as undoing bolts, but I wasn't sure about getting the belt back to proper tension so your description clarifies how to do it - sounds easy!

From my original problem (coil burned up) I have so far replaced coil (stock Bosch), rotor, distributor cap, and plugs. I went to buy a stock wire to connect coil to distributor (as this part melted in the coil fire) but it is not sold seperately - only as a whole set. The set was more than a set of Magnecor wires so I decided to try them out and see if the overall tune up helps my rough idle...

Car isn't running yet, so I think I'll get it going with the stock ignition wires in place and once back on the road and verified other everything else is working OK I will tackle removal of the compressor and install the Magnecors. I'll be able to see at that point with just that one mod if there is a difference how the car runs.

Thanks for the advice guys!