MSD 8481 Distributor Cap and Rotor Kit

Used this in a '93 LT1 Corvette. The ability to add fresh air ventilation is an excellent bonus.

Bringing a garage find Firehawk back to life after 10yrs required many new parts and I believe at some point the water pump failed and took out the Opti causing the long term storage of this beauty. Once I diagnosed all that was wrong I set out to buy parts. Including an opti. After reading all the whining on message boards from the experts about optisparks from the aftermarket and assessing the fact that GM does not! Offer new optisparks. Meaning $400+ for a rebuilt Opti and as I infer a used sensor. I went with a new Cardone Opti and added this cap and rotor as I'm of the opinion that the early Opti system has three issues. 1) they're not sealed well, two they're not vented, and 3) the rotors are crap. The MSD system addresses two of these issues. First I disassembled the Cardone Opti and trued the timing disc. A few thousands of run out but not bad, it's correct now. Next I installed the seals and used black rtv to seal around the sensor and green locktite the rotor screws. The MSD rotor is an amazing unit. Not Mickey Mouse melted together. It fit and cleared the Cardone perfect. Next I installed the cap, again I used the green locktite on the screws and MSD uses a 5th screw at the top be sure to use the screw and read the directions on how it should fit. It insures the cap is supported and sealed over that wide span at the top. Next I sealed the three bottom vent holes with black rtv. Let the unit sit over night to allow the rtv to set. Next day I installed it. Everything fit perfect the fifth screw just clears the water pump shaft and the stock OEM Delco wires work perfect with the MSD cap. The vent lines were run and the unit test fired before reinstalling the water pump. The LT1 awoke with just a few cranks after a ten year slumber and subsequent starts are with just a touch of the key. I anticipate a long life from the cap and rotor. Hope this review helps because there seems to be no shortage of negative reviews and few take the time to report positives. I guess most just drive the cars and enjoy the products. Bottom line take your time, plan what you're doing and don't force things. These parts should fit without forcing or abusing them. If it's dragging its not correct. Correct problems before the parts are installed. Follow directions and work in steps.

Great way and maybe only legit way to convert your unvented optispark to a vented one for durability due to a major design flaw by GM. The msd unit is well made & directions are fairly straight forward. I went a step further & sealed both rubber rings provided with rtv silicone for a waterproof vented unit. Very happy with the result. Nothing is getting in there this time but fresh air to exhaust the ozone out!

High quality. Sturdy. Looks great.

I bought this for my roadmaster wagon with a lt1. After installing the car ran horribly, upon investigating it was discovered that the spark was arching through the MSD cap to the engine. I replaced it with a delphi unit and the car runs great. Contacted MSD and they told me "it is a racing unit and carries no warranty". So now I have a 150 dollar wall decoration in my garage to remind me about this adventure. Never again will I trust MSD.***update***In the 90's I used nothing but MSD. It was a great company and a good product. My 96 Mustang GT still has a set of their wires. Then sometime ago they closed their factory and started producing everything in China. Quality took a dump. Their answer was to drop the warranty and live off the MSD name. I still have the roadmaster and it is still running great with the delphi unit 60,000 miles latter. I was a life long customer, I hope the 150 dollars they stole from me was worth the thousands in lost revenue from just me. I play with old cars all the time, I used to use MSD for the ignitions. Now I use ICE or stock. I have not thrown my money away to MSD since they stole from me.