I just bought a 94 LT1 that started misfiring around 3000 RPMS, and would get worse as the engine warmed up. The car had an MSD opti cap and rotor that is only a year old, but was getting a high pulse rate and low pulse rate code. So I decided to check it anyways. Turns out the screws for the rotor fell out and were just flopping around inside the cap. I got a new opti on the way anyways, and hopefully we will be in business.

 

Same thing happened to my two week old JEG's brand opti. Car died on the on ramp. Got an AC Delco from "thepartsladi" on ebay, and I've been problem free since then.
OEM ftw!!!

 

ive heard only bad things about the msd opti, cap, and rotor. when my opti goes out im def buying a oem original. ac delco is the best out there IMHO.

 

I've heard that the bolts backing out is a common problem and people have had to take them out and put a little threadlocker on them.

 

yes definitaly put some threadlocker on the screws before you install the opti. also put a thin bead of RTV around the rubber seal (where the two halves of the opti come together)

 

Along these same lines, does anyone know exactly what size Torx socket/driver is needed to remove and/or tighten the rotor screws??? Also, anyone know the exact thread size of the rotor screws??? I would sure like to replace those Torx heads with some simple hex head or maybe even phillips head screws. Why is GM sooooooo ...... in love with Torx head screws.

 

I know to remove the cap you have to use an 'E4' (inverted torx) socket. I don't remember if that is the same socket I used to remove and thread lock my rotor screws though.

 

I don't know, probably to frustrate the "average joe" who doesn't have a set in their toolbox. The better part is where they use the inverted torx fasteners, even alot of mechanics don't have those types of sockets in their toolbox.

 

Nope, it's NOT. You are correct the Optispark cap requires an "inverted" Torx bit, but the rotor screws are just a very small "regular" Torx screw. If you say you used the "E4" (inverted Torx) socket on the cap .... maybe the rotor screws just take a regular T-4 size Torx bit??? Anyone know for sure?

 

Haha, people at ACE hardware looked at me like I was crazy when I described it. I found it as AZ.

 

Checkers carries the inverted torx set for about $15.00 and I think the rotor screws are a t-6

 

here's what I found when I removed the cap from my Opti.

One screw was loose and the other was rattling around inside. I put threadlocker on when I put the new one in.

 

If you look closely, that's not your only problem, one of your plastic rivets is broken as well. When my oem opti (140K on the clock) when bad, it was a broken plastic rivet that was the culprit. When my two week old JEG's brand opti went bad, it was the rotor screws backing out that detached the rotor. Now with a new AC Delco installed, no problems thus far.

 

IMO the reason guy have good lucjk with new OEM optis is because the come assembled.

I have no problem with my MSD cap and rotor kit then again I put it together right even using the admittedly small screws supplied, that was 15K miles ago or so.

 

What? No confidence in performance parts made in Texas (MSD in El Paso)!

Both the GM and MSD Optis have their strong and weak points, however, for performance applications I still believe the MSD Opti is the best option.

WD