I have this wire loom. http://summitracing.com/parts/rnm-1102s It is nice and keeps the wires neat and out of the way. I have MSD 8.5mm super conductor wires.
The wideband has been showing a bad lean spike with a bad hesitation at tip in up to around ¼-½ throttle. I tried everything I could with the accelerator pump. I went to a 50cc diaphragm, every pump cam, and even a .056 nozzle with nothing helping. It seemed to be getting worse so I put the carb back to out of the box settings and it was almost undrivable. As a last ditch effort, I looked under the hood in pitch black darkness.
Every 5-10 seconds, I see a blue swirl come from the area towards the back where all 4 wires go through the loom. I can't see where exactly. As soon as I turn my flashlight on I can't see it any more. Maybe I should watch it again in low light instead of pitch black. It seems a little worse on the right side but both sides do it. Would an ohm test find the bad wire(s)? It had the lean spike before I had the loom. Do I need new wires? Could this be my lean spike and hesitation?
What would be the best wires? Is the low resistance of the super conductor that great?
The wideband has been showing a bad lean spike with a bad hesitation at tip in up to around ¼-½ throttle. I tried everything I could with the accelerator pump. I went to a 50cc diaphragm, every pump cam, and even a .056 nozzle with nothing helping. It seemed to be getting worse so I put the carb back to out of the box settings and it was almost undrivable. As a last ditch effort, I looked under the hood in pitch black darkness.
Every 5-10 seconds, I see a blue swirl come from the area towards the back where all 4 wires go through the loom. I can't see where exactly. As soon as I turn my flashlight on I can't see it any more. Maybe I should watch it again in low light instead of pitch black. It seems a little worse on the right side but both sides do it. Would an ohm test find the bad wire(s)? It had the lean spike before I had the loom. Do I need new wires? Could this be my lean spike and hesitation?
What would be the best wires? Is the low resistance of the super conductor that great?
Yes, ohming out the wires will identify if the issue is wire related. As a general rule, spark plug wires either work or don't. If they were casuing the issue, then I'd expect that the problem would be present under more circumstances than you've described. With that in mind, I'd check that the timing mechanical advance is moving freely via a timing light, and then for vacuum leaks. I'd be leaning towards vac leaks due to you identyfing that alot of carb adjustment have led to no improvement.
How long has this been going on (is this a fresh rebuild 1st startup situation)?
Keep in mind, when you move the throttle plates and the vacuum GAUGE reading drops that the vacuum (air movement) is still present, but it is acting on a different section of the carb circuitry. Hence, a good vacuum leak boogers up the entire carb tune.
The timing is 14° initial, 10° vacuum, 36° by 3200 rpm. It has been doing this for a while, it has just kept getting worse. It always felt like an electrical miss, but the wideband was fooling me and made me think it was an accelerator pump. I know I do have spark leaking because I can see it.
The wideband has been showing a bad lean spike with a bad hesitation at tip in up to around ¼-½ throttle. I tried everything I could with the accelerator pump. I went to a 50cc diaphragm, every pump cam, and even a .056 nozzle with nothing helping. It seemed to be getting worse so I put the carb back to out of the box settings and it was almost undrivable. As a last ditch effort, I looked under the hood in pitch black darkness.
Every 5-10 seconds, I see a blue swirl come from the area towards the back where all 4 wires go through the loom. I can't see where exactly. As soon as I turn my flashlight on I can't see it any more. Maybe I should watch it again in low light instead of pitch black. It seems a little worse on the right side but both sides do it. Would an ohm test find the bad wire(s)? It had the lean spike before I had the loom. Do I need new wires? Could this be my lean spike and hesitation?
What would be the best wires? Is the low resistance of the super conductor that great?
Sounds like the insulation is failing and you're getting cross over which might be a voltage leak or an induced voltage into adjacent and parallel wires.
I'd be a lot less concerned with neat looking wires and more with getting adequate separation between them. Secondary wires should never run parallel to each other and where they must cross these should occur at
90 degrees or as close to that as possible. Try to keep these crossovers with a quarter to 3/8ths inch between the wires, use plastic loom separaters to insure they stay that way.
My preference in wires runs to Taylor Spiro cores.
Wide band FA ratio indicators are really showing you what the combustion is doing not what the carburetor is doing although it, valve train condition, effective compression, and ignition are all contributors to the burn.
Secondary wires is another name for plug wires, i.e. the secondary side of the ignition coil, all the other wires on a car but specifically the points to coil and coil to ignition switch wiring is the primary side or primary wiring
They run parallel through the loom but have around ½" between each one. When they go behind the valve cover, they're sort of clumped together. It is such a pain to get them out of that loom I think I'd just like to replace the wires while I'm at it? Are those Accel ceramic ones any account? I do have tight header clearance.
I had just enough light to see. I soaked everything down water and started it. No arcing at all, everything looked normal. It was about enough time for everything to dry out and I was about to give up and saw it. Blue sparks would intermittently jump out the side of the wire to the valve cover stud. Probably one or two every 3-5 seconds. I could not see any bad spots and I could rub the wire and it would not bite me. Maybe it was easier for the spark to go to the plug than through my hand.
How can a spark jump out of what looks like a perfectly insulated wire? I'm sure I need new wires, but could there be more to it like a bad coil or coil ground?
Since my previous guesses were incorrect I lace out another. The wire(s) are bad. Change them all. At the recommendation of members here, I put on a set of the Taylors around June and never had one fail. I know it doesn't sound like a long time, but I had 3 of them routed under a turbo that had melted one or all 3, 3 times previously in less than 2 weeks - they can take ALOT of heat. And they feel like twice the wire of an Accel. The local speed shop stocked them for less than $50.
Hey man, nothing wrong with that. It's hard to diagnose a problem xxxx miles apart with only my description to work with. I will try the Taylor wires. Glad I asked about the Accels. That ceramic looked enticing.
FIXED!!! I changed the plug wires and my miss/lean spike is finally gone! I need to lean the accelerator pump out where I richened it trying to compensate.
I had MSD wires. I never did like the "spongey is it on or is it not feel". I got the Taylor wires with 135° boots which work GREAT on my big block. There is no spongey feel with these. A good firm positive snap. I cut them to length, crimped on the ends, and all is good!
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