What is cam overlap, and would I have it on a stock cam?

My idle does seem "lopey" when I set the static timing to around 10 degrees BTDC. If I go higher, like 20 or more, it smooths out, but that's not a good idea I take it. I verified that my harmonic balancer isn't slipped. I wonder if those goobers put some hi performance cam in there. If they did, it sure doesn't run like it, it doesn't feel any more powerful than the old engine.

Though, now that you mention it, I do not know for sure if my cam is stock spec, I would have to ask the rebuilder what cam he used. I was given the impression it would be an all stock setup.

Is an H or X crossover part of the exhaust? Or are you talking about the exhaust crossover passage in the stock intake manifold? I have the stock iron intake.

How does the Crane compare to the Duraspark? I would definitely like to upgrade my ignition system IF it helps performance, but I thought that the stock system was supposed to be sufficient if it's not broken in some way.

 

OK, update:

The coil is "Duralast Gold" and it has written on the outside "FOR USE WITH EXTERNAL RESISTOR". Also, it has the screw-on type connectors.

When I bought it, the guy looked up the coil in the computer and got me one that had these little push-on connectors, but the wiring in the vehicle did not have those connectors and the old coil had screw-on connectors. So the guy said, Oh, and went back and got a different coil that had screw-on connectors. I wonder if that first coil was the right one and this one is for points or something.

Another thing - I was looking at my stator, and I don't know how it is supposed to be, but mine looks jacked up. First of all, the metal spokes that the magnet senses are actually touching the magnetic sensor coil. The magnetic sensor assembly is held on with 2 rivets and they look like they have become all floppy and loose. The magnetic pull of the sensor is making it stick to the little spokes. It seems like that would make it grind on the spokes and cause some kind of a problem.

The stator passed the resistance tests Autozone has on their website though. It just seems like it shouldn't be touching, isn't there supposed to be an air gap between the spokes and the sensor? Would that cause a problem?

Another thing, I connected my multimeter between the orange and purple leads, and it was about 680 ohms. The Autozone page doesn't say how many ohms it should be between these 2 points. However, when I wiggled the magnetic sensor (it is loose on its mount) the resistance jumped around all over the place and sometimes would go to "infinite" resistence or open circuit, like there is a short in the wiring.

So, even though I don't see how the stator could affect the strength or color of the spark, it does seem like my stator is pretty messed up, probably should fix or replace?

 

Umm, ok, so my Dad did me a favor and picked up a new stator for the rotor, it was only $21!

Comparing it to the old one, this new one DEFINITELY does not flop around like the old one. The new one is a very solid piece, there is no room for movement anywhere. The old one had like 3 different places where it would move or have play. The new one does not TOUCH the metal spokes when they turn.

So, now I am wondering, since the metal spokes were rubbing on the old stator when it spun, could the spokes have worn down? Is there a spec clearance for the gap between the spoke and the stator? I wonder if I can buy this spoked piece, anyone know the name of it?

edit: ah screw it, I called autozone again and the whole distributor is like $40 to replace, I think I will return the $21 stator and just buy the replacement distributor for $20 more, unless you guys have a better idea. I won't do anything until tomorrow so hopefully you can give me some advice.

 

Sounds like cheap insurance. Keep the old one around just in case.

But, in my opinion, that wouldn't cause an orange spark. The Duraspark triggers off the rotor/stator. The Duraspark itself generates the pulse to the coil, the duration or timing of the trigger doesn't effect the end result. Unless it's some kinda hinky amplifier setup instead of a simple switcher.

I do know this: I had a Duraspark, w/stock coil, all perfect, had an orange spark. Installed MSD with an MSD coil (basically stock-looking except for the label and red paint) and NICE blue multi-spark.

I think this was asked before, and I didn't see an answer. Are you seeing this orange spark when cranking and not running? Put a spark plug on the end of one of the plug wires, ground the plug and start 'er up - it'll run rough but who cares. Check the spark at the test plug. If it's blue, you're fine there.

The loose stator/rotor WOULD effect your timing though. With that walking around all over the place, that's not good. PLUS, if the thing was wobbling enough, the gap would be too big and not trigger the Duraspark causing a random miss.

So, definitely, GET THE DIZZY!

 

OK I got the new dizzy! I'm gonna stab the dizzy right now!

I also stumbled upon a performance shop while I was on my way back from Autozone, I had never been in this shope before, it was called Wilky's. They had a whole mess of engine blocks, heads, pistons, etc. sitting around with price tags on them, some builders, some ready to go... They also had lots of car parts, performance and otherwise. They seemed to have quite a selection, and specialize in older cars and hotrods.

My Dad was with me and ran into an old friend there who is a mechanic by trade and owns his own shop with a bunch of mechanics under him. He told us that the shop is good and introduced us to the owner and said we could trust him.

Anyway, long story short, I got to talking to Wilky and I mentioned to him that I was considering an MSD ignition, and how I really wanted to have a good powerful ignition, so at least I wouldn't have to worry about that. Well, he very strongly suggested that I NOT buy the MSD, but instead buy the Mallory Hyfire 6. Well, he talked me into it... for about $180 I walked out of there with a Hyfire 6 ignition system and a Mallory coil, this should be fun to install! One thing that was holding me back from buying the MSD was the price, I was looking at close to $300. Anyways, Wilky says the Mallory works better. Even if it doesn't... the price is right I'm excited!

 

"Wilky says the Mallory works better" is this because he sells Mallory and not other brands?

.....=o&o>.....

 

He had both MSD and Mallory, he said when I was ready to buy it "I'll sell you the MSD if you want, but I really think the Mallory is better".

So here's the latest: I finished installing the Mallory ignition box! I took my time wiring everything so I could do a good job, making sure not to re-use any of the stock wiring except for the old positive coil signal, which was used for the ignition signal on the new box.

With the new dizzy and the Mallory box, the truck idles amazingly smooth and runs so smooth! I am very happy with the results of the job. Still looks like it is running a little hot, but I need to get a temp gauge that shows the actual temp in degrees F before I know for sure. The thing is when I put in the new engine I replaced the temp sensor on the intake. It was a Wells part and it might not be calibrated exactly like the original so I am not sure how far up the gauge means normal temp.

I did not replace the coil though because I ran into a possible problem, the coil Wilky sold me says right on it "do not use with aftermarket capacitative discharge ignitions like the Mallory Hyfire". That is funny because it is a Mallory coil and the guy said it was a good one to use with this ignition... grr...

Anyway, I couldn't afford the MSD so it's Mallory for me!

 

The MSD is somewhat "known" to blow up on you for no reason. I've done it, but it had a reason! I pulled the + from the coil to keep it from firing when I was cranking over the motor. Wrong option.

Greg (Gtex) has blown one or more also... but after all the discussions I think he admitted it was his fault

But they are touchy...

 

What about the Mallory, any opinions about those?


Not that it matters, it's too late lol... I already have it all wired up in there snug as a bug, with wire loom on all the wires and different colors of electrical tape..hehe... looks cool, I like doing wiring jobs, but only if I am gonna do a GOOD wiring job! I hate crappy wiring jobs they make me want to hurt people.

All ignition related wire is wire-loomed and wrapped, I also started putting wire loom on some other areas of the stock wiring to protect it, but I'll do the rest later, everything ignition related is done.

 

I have had two MSD failures that left me stranded, that's why I run a Allison (became Crane) and Crane ignitions. On your coils you shouldn't mix inductive coils with CD systems as well CD coils on inductive systems.
I prefer Inductive systems for the longer spark duration like 2,800 us (micro seconds) vs 300 or 400 us of Mallory's CD system. This is a 7 to 9.3 times longer spark duration.
Check this for a better explanation, www.rmlautomotive.com/ignition.html

.....=o&o>.....

 

Hey guys, update! This is really weird!

Just today, I replaced my coil, installed a Mallory Promaster 29440 coil. I have heard so many good things about this coil. I also replaced my spark plug wires with MSD spiral-wound wires, the 8mm ones. Before I had the cheapest Duralast wires from Autozone.

Now, here is the CRAZY part... My spark does not jump as far as it did with the old coil!!!!!!!!

The old coil was a Duralast Gold from Autozone, it was fairly cheap. This Promaster is supposed to be better. I am kind of confused... With the Promaster the spark will jump about half as far as it did with the Duralast coil.

SO, what gives here? This Promaster coil is definitely more expensive and has higher ratings.

Could it maybe be caused by the longer wire from the coil to the dizzy? On the old coil the wire was your normal, shorty wire because the coil was mounted on the intake manifold. Now, I mounted the Promaster coil on the sheet metal and the wire from the coil to the dizzy is like 2.5 feet long to reach.

This seems pretty strange to me, but the color of the spark looks more blue than the old one, even though it won't jump as far.

I wonder does it matter how far the spark will jump? I heard that how far the spark will jump is a function of how many volts the coil puts out, but that higher volts aren't necessarily the purpose of a high power coil, but rather, higher amps?

I dunno, I am a little bit worried, I expected the spark to jump farther on the new coil not less...

Another thing I wondered, when I disconnect the spark plug wire from the plug, maybe now instead of arcing from the wire to the block, maybe it is finding some shorter or easier place to arc to, maybe inside the dizzy for example? It didn't do that before though...

Anyway I am confused here...

 

You mounted the new coil "on the sheetmetal" ??? Where? Make sure it has a VERY GOOD ground back to the motor.

 

Welcome to the coil sales pitch world, brand X has 45KV output, brand Y has 52KV output which one do you think Mr. public will chose? This is the game manufactures play on lower end cheapo can coils as you can't have HV and high joule (current) output at the plug not primary (at the plug is what counts) with points or low cost point conversion units as they can't handle the higher current switching. This is where higher dollar units come to play as they can handle higher current switching for the coil and not require a ballast or resistor wire.
Check both coils for their voltage and current (joules) output, you already found out a blue spark, shorter spark length.
Unless you have high ohms per / ft ignition wire there shouldn't be a difference in spark from relocating the coil farther away.
Crane's FireWire 8.5mm is 25 ohms per / ft.

.....=o&o>.....

 

The Promaster coil has a plastic outside, where you mount it doesn't make any difference, there is no chassis ground on the outside of the coil. There are the + and - terminals of the coil and the plug that goes to the dizzy and that's it.

 

Well I expected this new coil to make the spark jump farther from the plug wire to the block, but last night I tested it some more, and I was able to see that what happens is, if you get more than like 1" away from the block, the spark just goes somewhere else!!! It doesn't bother trying to jump a 1" gap, iinstead the spark energy arcs all over the outside of the plug wire like tiny sheet lightning, it's quite an amazing looking effect.

And these are MSD wires, supposed to be good stuff! BUt they are not able to contain the spark, it is just too high of voltage I guess?

Another thing I noticed, with the Promaster coil, if I put the spark plug wire too far away from the block, the electricity arcs all over the outside of the wire and sparks shoot from the outside of the wire onto things like belts, anything metal, even rubber hoses... BUT with the cheaper Gold coil, all the arcing happens on the coil itself... If I hold the wire too far away from the spark to jump the gap, it just arcs like crazy all over the coil terminals! The Promaster coil must have better isolation to prevent this type of arcing at the coil.

I think in real world application that wouldn't happen because the spark plug gap will be a much easier path.

Also, I was noticing a yellow spark but that was the spark jumping 1/2 to 3/4 inch from the plug to the block... which I realize now is kind of stupid, doesn't tell you that much... When I hook up the a spark plug and make the plug gap bigger than it would ever be in real life, I see a nice blue spark. It was only orange when I was doing dumb stuff like making the spark jump close to an inch...

So anyways.. bugh...