LT1 95-97 MSD cap and rotor ?'s

[LoudLT1]

auction site has a msd cap and rotor. its listed like this " Fits 1995 - 1997 LT1 Corvette , Camaro , Firebird (Without vacuum hoses)pn 84811.
what does "Without vacuum hoses" mean?? also is this a vented unit?? WILL THIS FIT MY 95 ?? anyone using the MSD Opti??. going to do a complete tune up and isnatll headers and other goodies at the same time.. my 112,000 mile Z28 still has original.
eddie

[LoudLT1]

how do i verify if i have the Optispark I or II. how do i identify the Optispark II ? the opti I is not vented correct? my 95 Z28 should have the vented optispark II ???
help
eddie

[fastTa]

According to the MSD site and Summit, part# 84811 appears to be a vented Opti version, which makes a II. They have part# 8481 which appears to be the non-vented version. I suspect is what the auction means by "without vacuum hoses" is "does not include hoses." In other words, they are not providing you with new hoses.

Here is a picture from Summit Racing of their MSD part#84811. You can clearly see that it has the provisions for the 2 vacuum hoses.

Google is your friend Ed!



Your 95 likely has a vented version II, if it is stock and original, BUT some 95's got the Opti I. Just look for two vacuum hoses on the lower corner on the driver's side of the Opti behind the plug wires. The one with the 2 vaccum hoses is the vented Opti II.

[96Camaro]

I agree, I think it means it just doesnt supply the hoses. Should work fine I would think.

[LoudLT1]

are they any good?
or should i go with a gm part?
i can pick up the msd version for $147 shipped!!
what you guys think??
thanks,
eddie

thanks for the info on my other questions. i completly missed the hoses thing

[Joe 1320]

In my opinion, for a few dollars more you can purchase a complete AC Delco optispark from one of the discount GM venders. That would be a complete plug and play for another 100K miles. The MSD cap and rotor is just that. It's not the entire distributer. I'm sure the MSD cap and rotor are good quality, but what if an unreplaced part fails?

[LoudLT1]

joe,
what doesnt the msd unit come with that the ac delco unit does?
never installed one have no clue
eddie

[fastTa]

joe,
what doesnt the msd unit come with that the ac delco unit does?
never installed one have no clue
eddie

Mainly the slotted disc, photo emitter, and receptor. The receptor and photo emitter rarely malfunction, but it is not impossible. The slotted disc is prone to some corrosion, but is also not likely. Just inspect your back half of your opti and look closely for any signs of corrosion. If you don't see any corrosion, you will be fine with just the cap and rotor if you are looking to save some money.

[LoudLT1]

kevin,
if i do need to pick any of these parts up slotted disc, photo emitter, and receptor. what do they run.
thanks,
eddie

[fastTa]

kevin,
if i do need to pick any of these parts up slotted disc, photo emitter, and receptor. what do they run.
thanks,
eddie

If you see any sign of corrosion, then just do as Joe suggested and pick up a Delco unit from Dal Slabaugh or Jason Cromer. Rob (Shoebox) has their contact info on his site.

[TraceZ]

Mainly the slotted disc, photo emitter, and receptor. The receptor and photo emitter rarely malfunction, but it is not impossible. The slotted disc is prone to some corrosion, but is also not likely. Just inspect your back half of your opti and look closely for any signs of corrosion. If you don't see any corrosion, you will be fine with just the cap and rotor if you are looking to save some money.

The bearing on the shaft can also wear out. The majority of opti failures are not the cap and rotor, but rather the sensors and the bearing.

I'd recommend getting a complete AC/Delco replacement opti.

[fastTa]

The bearing on the shaft can also wear out. The majority of opti failures are not the cap and rotor, but rather the sensors and the bearing.

I'd recommend getting a complete AC/Delco replacement opti.

Tracy, over 75%-80% of opti failures are the cap and rotor. The bearing is not uncommon to fail, but usually on very high mileage motors or due to an improperly installed opti.

Even if and when the optical receptor throws a hi-res or low-res code, it is noramally due to being blocked up with rust or other contamination from the carbon steel inner plate. Many of the optical pulse codes are most times caused by corroded wires in and around the opti as well. If you set a code for insufficient hi-res pulse, the engine still runs but you will suffer from a lack of timing accuracy. If you set an "active" code for loss of low-res pulse (more common), the PCM will shut down fuel and will consequently not run. It is possible to have a stored but not active low-res code and the engine still run. The low-res pulse lets the PCM know which cylinder is approaching TDC so it can appropriately pulse the injector and fire the plug. The high-res pulse references the cam position as the engine rotates between the low-res pulses.

The actual photo emitter and receptor themselves rarely fail.

[LoudLT1]

Dal Slabaugh or Jason Cromer website???
or email address???
anyone..
thanks