Help troubleshooting MSD6A

[sevenracer]

I've installed an MSD box in my IT7 and I'm having some issues. Hoping some one can help me troubleshoot.

Setup:

Leading-
Single MSD6A
triggered off the leading mag pickup
Using the MSD supplied trigger twisted pair wire
MSD output going to an MSD blaster2 which goes to the distriubtor cap "L" input
locked distributor

Trailing-
Stock except for a blaster 2 coil

The problem:
Car rev's sluggishly - definitely down on power. Really runs like crap if I disconnect the trailing, but it will still run. It sounds like there's arcing at or inside the distributor. I get a strobe with my timing gun on the leading, but it's sort of "always on" - I never see the timing marks on the pulley. Trailing timing looks fine.

What I've tried:
Trigger wires are very well separated from any other electrical
Ignition wires are well spaced
If I go back to stock, the car runs great, and the timing looks fine
Rotor cap and button are fresh and clean

Questions:
Can you time an MSD6A with an inductive pickup timing gun? Or does that multiple spark stuff mess things up?
The MSD instructions say that you may need to drill holes in the disty cap due to air ionization. I pulled the blank plug off the cap - no effect. Anybody else had to do this?
I guess my next move is to trigger off the ignitor output and see what that does.
Any other suggestions?

Help!!
Neil Gueldner
N Car region

[lateapex911]

Well, I honestly have little to suggest, sorry. I would pull the plugs during cranking without the MSD, and then with, and observe the spark. I have mSD on my Poersche 911, and I remember needing a VERY good power supply to it. So double check that.

As an aside, I'd like to hear the experts thoughts on the need for MSD in a rotary. As we spend 90% of our time at or above 6K rpm, where I understand the MSD has no effect, is there really a point in doing the modification?? If there's no more hp as a result, then to me it's just extra weight, extra money, and extra complication that can fail later.

So, what are the real known benefits?

[bldn10]

A 2nd gen. I used to have came w/ one and I ran it and w/o and could tell no difference. My ex-SpeedSource car did not come w/ one and I figure if an MSD would make it faster, those guys would have had it.

[kbailey]

Hey Neil,

I can bring a couple 6A boxes from Eva's car down this weekend for you to try if you think it's a bad box. Are you running the early distributor or later? If it's the early style I can go trace the wires in her car tomorrow and see where they go.

You could also ping Jim or Greg and see how they are set up for the trigger. I don't remember doing anything special to time their cars......

Just make sure your running well come Saturday. I'm counting on you to lead me around the track!

[JeffYoung]

Guys, I am told that there is a noticeable difference with the MSD (and this was my experience) in carb cars, not so much in FI cars. The MSD gives a better spark that cleans up the carbś imprecise fuel-air mixture. With FI, it is not so critical.

My car pulled much cleaner to the redline (a whopping 6k) withthe MSD.

[sevenracer]

I know that Paul Yaw raved about them on his site, and some of the fast 7's have them - two of them - one for leading and one for trailing?

Thanks for the offer Kevin. If it's not a whole lot of work, bring one along. My gut tells me it's something other than the box though.