Ok well I spent a half hour typing the last one out to have a problem and lost everything so i'm gonna be quick describing this one.

We just swapped a 351 back into the car and worked out a bunch of bugs. One of the bugs was the ignition box problems we were having ( I didnt know at the time the duraspark box's weren't good). Well I know now and at 20 bucks a pop no big deal, i'll buy them as they go out and stock pile them.

First the old box that was in there was used, however it fired the car and it would run fine for awhile and then just shut off as if you turned the key off. Thats a tall tail sign that the duraspark is bad. So I went out and got a new box and now the car refuses to even try to fire, it just sits there and cranks. Now how could a faulty box fire the car perfect and a new one not do the same?! Also in the schematic i'm gonna list below there is a white wire that is run over to the solenoid that is optional, I dont have it hooked up because on both old and new boxes it would just fire and not run without continuing to crank. I also have the electronic choke wire run over to my coil. This wasn't a problem however with the old box. I'm stumped and have no idea at this point and need help.

Heres the schematic we used for the wiring
http://www.mustangsteve.com/conversion.html

 

Are you getting any spark at all? Have yiou pulled a plug & checked?

 

they made a couple different dura boxes. this is how mine goes. 3 wires coming from the distributor plug into the 4 wire plug from the box.... green to coil, black, purple and red go to the plug in the box. then the white and red from the box..... white to starter solonoid 'I' post. red to ignition. the other white wire is a retard wire. not a must but used when starting. i know what your going through!! it sucks! let me know what wires your have in order coming out of your box.....

 

^the same exact order as yours. I beleive in that schematic you have to use the same setup.

I'm sure i'm not getting spark or it would fire, I know I have fuel as I just got the carb rebuilt and tuned with the old malfunctioning box in.

My big question is why will the old malfunctioning box fire the car right up and the new one not at all? Maybe I got a faulty box?

 

I've seen GM Hei's run perfectly fine. Swap in a high compression engine and ZERO spark. Pull the plug out and it sparks. Under compression, no spark. Not sure if Duraspark is similar. Good fine ignition for stock engines but under big pressure, no spark.

 

dura sparks are supposed to decent... alot of people use them in motor swaps. or like jfsram said they use a gm hei setup...... dura sparks weak point is high rpms, and heat,. but pull one plug and make sure your not getting spark. if not, try plugging back in your old dura spark and see what happens. green coil wire is on the (-) post right? or maybe you have your two white wires mixed up? or coil took a pooh. take a look at your cap and rotor. it sucks brother. i know. took me a whole day to figure out what was what.

 

i just rememberd the wire i over looked when i was hooking up mine... make sure you have a wire on the (+) of the coil "T" in to white wire running to your ignition. let me know...

 

Yea the coil is new, the cap and rotor aren't though, however i'm almost positive it's a box and I think i'm gonna go swap it and try a new one.

 

Ok update:

I went out and bought a new box for ****s and giggles to see if it would work, I was highly doubting it. Sure enough it didn't work at all. Again I went and dug the old faulty box out that I took off and it fired the car right up, right after this I plugged it onto the new one and got nothing. I've checked all my connections and they look good. So maybe do you think they changed the wiring in the newer boxes somehow?

 

yeah i have 3 different boxes in my garage that i tried before i found the right one. so i know their are at least 3 versions of durasparks and all of them have different wiring coming out of them. make sure the wires are in the same location. for example mine go in this order.. white, orange, purple, geern/black (space)red green.