Rickerdo

I just bought an MSD 8381 distributor (94 spline drive model). With both distributors out of the car, and the flat indexing spline at 12 o'clock, the rotors are 180 degrees opposite of each other. In other words, one rotor points to 12 o'clock and the other rotor points to 6 o'clock.

I called MSD tech support who said that it's impossible for that to happen and just wanted me to get a replacement under warranty. So now I have to wait another 3-5 days to get the new one and HOPE it's not backwards too.

Has anyone out there ever experienced anything like this with the MSD 8381?

jaysz2893

my MSD8381 was fine. Cant you just unscrew the rotor and turn it 180 degrees and screw it back on? Bummer you have to wait for a new one.

Rickerdo

That would be too easy! There is an indexing pin on the back of the rotor, so I cut it off and tried to put the rotor back on 180 degrees in the opposite direction. No go. The screw holes are slightly off center so only one screw hole lines up, not both.

Unless MSD makes a rotor for that distributor that points 180 degrees in the opposite direction, I don't see how the distributor could physically be assembled incorrectly. Even the crank position slots line up with the old factory opti. It's just the rotor that's off.

Just wondering if I got a bad MSD distributor or if anyone else experienced anything like this as well.

Elliott's94Z

iTrader: (12)

Your best route to go is, buy a OEM opti and put on the MSD rotor and cap. MSD opti's themselves have not been that reliable.

tdevil55

iTrader: (23)

From my experience, you can’t put the MSD rotor on a GM Opti side. I tried it before, will not fit right. Without the rubber ring, the MSD rotor sits too flush to the opti and will not screw down right and will bind against it. With the rubber ring underneath the rotor, it wouldn’t let the rotor sit right to be able to screw the rotor down.

The MSD cap will fit on the GM opti, which is what I have now. This may not be the case for all GM style optis, but the one I have wouldn’t let the MSD rotor fit.

What I did do was copy the MSD rotor setup and drilled out the back plastic retainer on the rotor and found a small screw to fit(computer type screw, used in computers to hold the board down), and screwed it in the metal T bar and plastic to help secure the T bar on. I also put a little bit of brown gasket sealer on the back side to cover the tip of the screw.

This is just my experience trying to use a GM bottom and a good MSD top on the opti build.

Elliott's94Z

iTrader: (12)

Well I'm running a OEM Opti with a MSD Rotor and Cap on my 94. Maybe I'm a rare breed....doubt it though.

Rickerdo

I seriously considered going that route too, but after two GM optis in my Formula to date (125k miles), I decided it's time to try something different because I don't EVER want to do it again. Well, at least not because I drove through a puddle.

I've read about modifying stock optis for the venting, but figured it would be easier (and possibly cheaper) in the long run to just get a complete kit from MSD. I'm beginning to think otherwise now.

Thanks for all the input guys!

Rickerdo

Well, the new distributor came in today. The old 'bird fired right up after installing it. I guess in hindsight I could have adjusted the rotor's position by taking it off and turning the allen key'd bolt behind the rotor. I just didn't want to mess with it.

So far so good!