From what I understand, the non-vented to vented opti switch was made in mid year 94. I was wondering how I could tell if I have a mid year with a vented or an early year with a sealed. Is it something I will be able to see, or do I have to check the VIN?

Thanks,
Brandon

 

I believe 94s only got non-vented. You should upgrade to a vented opti. Do a search to see what you need.

 

From what GM has said it could be either, depending on the date of manufacturring. Changing to vented requires new timing gears and cover from what I was told, so I would rather not do that. If I have vented already I will be very happy.

How are things going in MA Kat?

 

I have never seen a 94 with a vented Opti, If you have a vented one which I doubt there are 2 vacuum lines coming out the bottom of the Opti. You can vent a 94 yourself and buy the factory vacuum lines. If you do a search you will come up with instructions on DIY.

 

Never have heard about a mid-year change on the f-body. AFAIK, 93-94 is non-vented and 95-97 is vented. Never seen it any different.

 

If you want to tell the difference easily the car will have a port on your intake elbow to vent to the vented opti's.

Also the connector on the vented optis is about 2.5 inches long into the opti the non vented is only about a 1/2 inch.

More than likely your car is non-vented.

My first non vented opti lasted 120K and was still good when i redid my motor, my current new non vented is doing just fine as well.

Non vented are about a 100 dollars more so you can put that towards the conversion kit needed to go to non vented if you feel it is needed.

 

Going pretty good, I'm in school again to get certified. Hows the hurricane weather? Just switch to vented,its superior.

 

The hurricanes suck pretty bad, but everything else is going great. How's sephus doing?

 

I have a VERY late 1994.... within 200 of the last VIN for the year. It came from the factory with a non-vented Opti. I had to buy all new parts... timing cover, LT4 ED timing set, etc for the conversion to a vented system.

 

His new name is "all star" since I only do weekends now he feels the need to think hes awesome and tell everyone what to do.