i think my opti is going, the car trembles (rocks back and forth)while driving and it seems like it looses power and regains it and then looses again. i guess this is the best way to describe my problem. let me know what you think it might be.

also i wanted to know if i could put a vented one on a 94 LT1 with out any other modifications to do? also is this a good idea.

 

I would rule out several other things like fuel pressure, injector cleanliness, wires plugs and EGR, IAC and MAP and TPS before going on.

You can switch to the vented type but your timing cover and Cam has to change since the distributor drive has to go into the end of the cam.

Look at this
http://www.automotiverebuilder.com/a...nts/99928c.gif

This is a picture of the distributor drive
http://www.automotiverebuilder.com/a...nts/99928j.gif

You also obviously have to route vacuum lines and a restrictor.