6al and plug gaps

Ok I read an ealier post on this topic. It seems that plug gap is variable . Each set-up a little different. Now my problem is I could not even get my fresh motor to start @ .050 and @.035 it runs but seems to lack power. I'm running accel shorty plugs (574's) and MSD Blaster SS coil. MSD distibutor and 8.5mm MSD wires aprox. 9.5:1 . With this set-up shouldn't plug gap be just fine tuning detail ? Or am I missing something.....Maybe a bad component?????

 

Yep you have something else going on. Weak spark??

 

That's what I'm thinking......but what would cause it ?????

 

Coil not getting enough voltage...MSD box not getting enough voltage. Box needs 9 volts minimum. Coil...Some need 12 volts...Some are fine with less. Find out which coil you have...Good luck!!!

 

Can you bypass the 6al box and just hookup the coil to the car's wiring? That will at least isolate the box. The 6al provides power and ground to the coil. Is there any chance the wires are reversed?

 

I never thought of that. But would it run at all if it was reversed?

 

I have had MSD cables come reversed from the factory.Somewhere in the harness or box the purple and green are switched.It will still run but with poor output

 

Well just double checked the pos. and neg on the coil they are right orange on pos. and black on neg. I also checked the voltage to the box ..12.5v and re-checked the block to neg terminal on the battery and had 1.2 olms . I'm running out of posibilities . The 6AL is brand new last fall. I had a little trouble getting the tach to work but after wiggling the wires it worked fine. Maybe I'm barking up the wrong tree

 

Thanks Darek ! How did you troubleshoot it to be sure? As I recall the puple and green go to the distributor. It's been a few months since I wired it.

 

Where do you have the large red wire connected to for a power source? That is the main power wire and should be connected directly to a battery source. The smaller red wire is the turn on wire and should come from a switched ignition source, I used the factory ignition wire.

 

I had a problem like this when I went to start my engine for the first time. Does ur msd have a cylinder select. Mine does, and I put it on 8 thinking that was the right one since I had a v8. Nope that was the anti theft selection. It was kinda funny once I figured it out. But I was pretty pissed when it wouldn't start. Good luck

 

Normally on MSD igntions it is already setup for a v8 you only need to splice the wires if your using it on a v6, i6 or 4 banger. Try setting the plug gap to 45 and check all the connections again. Sounds like a failing coil.

 

Dissconnect the Purple/green harness from both ends and plug it into itself forming a circle purple and green wires should line up.If not the wires got plugged into the connectors wrong at the factory. Had this happen on a MSD distributor,how i figured that out was compared a friends distributor and mine was different than his.Had to pull wires out of connectors and switch them.

 

Thanks for all the input guys!!! To address the reversed violet and green wires I accually reversed the the leads and the motor ran WORSE so I Know that thse wires are right .
To the question about where my battery leads are connected. My battery is in the trunk and I ran a resistance check to my leads in the engine comp. to the battery and I got 1 ohm and my MSD is connected to these leads.
In troublesooting the distributor wiring I discovered I had 100 ohms to ground through the box on the neg side. This seems high to me but I can't find a reference to this. Shouldn't this be 0 ?
The motor will run well enough to drive down the road but stumbles on acceleration and idles poorly . I can not get it to idle at less than 1000.
As I said I'm running out of ideas

 

Oh Yea and the coil is a new MSD Blaster SS. I know we sometimes get bad parts fom the factory but...... It seems unlikely