Periodic miss is eluding me. Accepting random suggestions.

How long did you stare into the darkness at the engine? I suggest at least 3 to 5 minutes so that your eyes stabilize. The longer the better.

 

We didn't stare long. I figured it would put on a "light show" so when it didn't spark and arc anywhere, we shut it down.

Jay, thanks for being so generous and giving me FIVE cents worth...everyone else only gives me TWO!

I haven't checked the voltage since I installed the pertronix setup, and am assuming it is correct, but it never hurts to check it again.

 

Trust me, you will be amazed what you see if you wait. It's not like you will see the kinda spark from a plug. The light show becomes more visable as time in the darkness goes by. I have seen plug wires that glow and not actualy spark to ground.

 

I may try that out tonight. I would really like to see one of these light shows!

So, just set up a couple of lawn chairs, pop open a few beers, and invite the neighbors over...

 

Sounds fun. Just get it as dark as possible with out tripping.

 

I just bought new wires, but want to try the light show out first before I swap them.

Without going into a bunch of hassle over the Accel wires (ordering, being sure they have the right ends, cutting them to fit, etc.), I just asked for 88 Mustang GT 5.0 stock replacement wires (Motorcraft). I am running a just barely over stock ingnition system so I figured these wires should work for me for the next couple years.

 

New wires installed (I couldn't wait til tonight for the spark show) and took it out. There was some improvement.

But, only above 3000 rpms. Cruising at 60, 65, or 70 and either there is no more miss, or it is just so minor that I don't hear it.

If I put it in D and accellerate quickly, it will sputter a little until I get it up to 3500 or so, and then as long as I keep it in the power band, no misses (but chirps through all 3 gears...I will have to work on THAT problem later on..)

But if I cruise around 40 mph, or under 3500 rpms, it will spit and miss just like it did before.

Should I start looking at a fuel issue (maybe a little lean?), or is this what i have to live with for building a 3500-6500 rpm engine.

 

try backing your idle screws out 1/2 a turn.

 

You can still have the party. Only now your mostly watching around the plugs.

 

i cant help it... its your dang flux compasiter

have you reinstalled your distributor lately??? could be put in wrong.... out of time???(ha ha)

dont know that much about electrical except it blows

 

I don't remember, are you running a vacuum advance? Might try loosening it up a tad or so if you are. SOme of the rebuilt dizzys will have up to 70 degrees of vacuum advance dialed in and can cause problems like yours once in a while
50 miles on an engine could also explain a valve sticking just a little causing it to open or close a little slow
clint

 

I was originally NOT running vacuum advance, but it was maxing out around 30 degrees. So I hooked it up and tried it again and it really woke the engine up. But it is getting around (guessing here, it is off the scribed lines) 45 or 50 degrees total timing.

I will mess with the carb a bit and see if it isn't running lean.

Don't get me wrong, this car is running AWESOMELY, it just has this little quirk that probably only I can hear/feel.

 

so wait. your car was siting for a long time right?

if so you may have some rust or something on a valve seat causing one not to seal that well and causing the miss. thats just a random thought that poped into my head. probly a compression test or leak down test could help find this.

 

Yes, it sat since last February. But i ran it at least once a month just to keep the battery charged and then engine lubed.

It just ran on jackstands in the garage for 15 or 20 minutes at a time.

The miss is not steady enough for me to believe it is valve related. But you never know...

 

ummm,, how old is the fuel?