I just changed my stock opti to a new msd opti - w/fresh hoses. Those hoses were not on my stock opti. Can I just plug those two ends up?? Or do they have to by connected to the vac???

 

there is a reason they are vented... connect the hoses or you will be replacing that thing sooner than anyone wants to...

i know from experience with a gm one... it only took me 3 wks...(alot of humidity here)

 

the reason i did it was because my bottom vent tube boot split and i thought i would temporarly fix it by caping off the opti vents... NOT GOOD!!!

 

Hmmm did you get the correct opti for your 94? Your 94 should be non vented(no vent hoses), and the new msd sounds like it is the vented version, hence the hoses. Did it bolt up correctly???

 

The MSD opti's [early and late] are both vented..
And yes, I'd hook them up for sure..

 

One needs to be connected to the inlet elbow, to supply filtered air that has passed through the MAF sensor, and the other needs to be "teed" into the vacuum nipple on the side of the intake manifold for your EGR vacuum connection, to pull the air through the Opti.

 

The kit comes with a new hose and plug to put in the elbow for the fresh air tube.

 

I connected the vacuum side to the opti. I dont have it connected to the inlet elbow. I had a sts turbo put on and the elbow does not have a fitting for that. Can I just plug that vent up since the other one is connected to the vac??

 

Just drill a hole in the elbow .

 

No. You need air flow through the Opti to remove the ozone that builds up from the high voltage discharge - that's why GM added the vent system. And the air supply needs to be "metered" by the MAF, because that air ends up in the combustion chamber. Pulling full vacuum on the Opti with no air supply can deform the cover, and pull dirt in through the seals.

Do you still have the turbo? Is so, you need to be careful about where you pick up the air and vacuum connectons, to avoid pressuring the Opti. If you no longer have the turbo, you just need to drill a hole in the elbow and thread a fitting into it.