I bought a 78 F250 with a 460 C6 and the prior owner said the motor came out of 79 truck. The only numbers I found are d6ve on the intake mainfold and d6te on a tag on the distributor. I went to get plugs and a new cap and rotor from a parts store and the only cap and rotor that matched up was for a 71 Lincoln. It dosen't look like there are points in it and it has an MSD 6AL box hooked up. The plugs in the truck are gapped at .036 also. Should I just leave the gap alone or can I go to .044? It runs pretty good and I've only changed fluids so far.

 

Maybe it has something like an aftermarket Pertronix system?

Ignitor

 

It looks like one of those under the cap. Their website says you can use a bigger gap with their coil added. Just wanted some opinions before I change the plugs.

 

I would use the copper core Motorcraft's.

The recommendation is .044" for the DuraSpark ignition.
I'd imagine this is a good starting point.

With a Pertronix and a 6AL MSD it's certainly got a hot enough spark.

 

Most likely the previous owner for some reason went to the early style small dist cap, and then with the msd gapped the plugs down to keep from misfiring under the cap. If you get a (these are Autozone Duralast numbers, but any parts house should be able to cross them) F2103 cap and rotor, and a F958 cap spacer, you can get back to the big spacing rotor. I would suggest doing this, as the wider spacing under the cap will help prevent misfire, especially at larger plug gaps.

Next does the ignition module look like this:


or this?



If it looks like the second one, its the factory duraspark pickup, and its had the MSD added in place of the duraspark box. Not a problem either way, just curious.

Lastly, as for the gap, what kind of wires and coil are you running? If you are stepping to a wider gap, you need to make sure you have good wires and a coil to handle the added demand. Otherwise the coil will not strike the spark needed and the wires can bleed the spark out, resulting in worse performance than before. With stock parts (coil and wires) and the correct cap, going back to .044 gap is no problem. With performance wires and a hi output coil, you can step the gap to .050 or so with no issues and present a fatter/stronger spark in the combustion chamber to boot.

 

It looks like the second pic but there's no duraspark box or any other controls on the truck except the MSD box and voltage regulator. I have alot of wires that lead to no where. I put the .044 motorcraft platinum plugs in and it seems to run fine, drove 150 miles in one day and didn't have any hesitation or knock. The wires are 7mm silicone spiral core, not sure of brand but I will probably get some 8 or 8.5mm wires in the future. I think the coil is stock and/or not a performance coil.

 

When you talk about rotor gap, not sure what you mean. I've never replaced a distributor just cap and rotor and I would just pull the old ones off and put the new ones on. No adjustments. What year should I order the new cap and rotor from? I would like to get a MSD but can't seem to find one that matches.

 

Where do you see "rotor gap"???
There is a reluctor wheel Air Gap specified for the DuraSpark II system.
In the photo above the blue and white pickup needs to be a certain distance from the crown like trigger that spins.

I know my truck uses the 'pancake' cap and adapter. The rotor is longer to reach out to the wire contacts.
<a href="http://www.flickr.com/photos/24183730@N03/2443359624/" title="IMG_2060 by Jim_Urrata, on Flickr"><img src="http://farm4.static.flickr.com/3088/2443359624_c2b6951ae3.jpg" width="375" height="500" alt="IMG_2060" /></a>

 

If you look at the cap from that is currently on there it should look like this



The one that is supposed to be on there will look like this



and have a spacer like this under it (its upside down in the pic)




If you look at the two caps, you will see the one on the bottom has a wider gap between the terminals

New Style



Old Style



The wider distance between the terminals on the new style allows for an increased plug gap with less chance of the spark jumping to the wrong terminal inside the cap (misfire). Even though the plug gap may only be .044, with a hot coil and ignition, the increased resistance of the air/fuel being compressed in the cylinder may actually cause the gap between the terminals to become the path of least resistance, allowing the spark to jump under the cap instead of traveling down the wire to the plug. The increased surface area under the new cap also helps dissipate static charge under the cap, which can also cause misfire at higher rpms.

As for the module, it is a duraspark module that has been wired to the MSD ignition box. Here is the link for the MSD instructions and wiring diagram.

https://www.msdignition.com/uploaded...5_frm29772.pdf

 

I understand what you're saying now. I had an 89 f250 460 and it looked like the pancake style cap so I didn't know what to do. I imagine I will need a kit since the rotor will be longer? If it's the same length, I would like to get the MSD cap and rotor. Since it's probably the factory coil, do you have any recommendations?

 

My preference is as follows:

• Mallory 29440 Coil
• Ford Racing 9mm wires
• Motorcraft Distributor cap, rotor, and spacer
• Motorcraft copper spark plugs

Add that in with the MSD-6AL box you already have, set the plug gap around .048 and you will be giving the motor a good hot fat spark to light things off.

 

Do you have a part number for the spacer. I tried 2 parts stores and they couldn't find it.

 

Napa has an Echlin #ECH FA151

Should cross to any other manufacturer

 

^^^ or a Duralast F958 (Autozone)