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Dale99 · 11-15-2012, 03:48 PM

My upper plenum is the correct for my year, 90-92, so it has a threaded boss for the bracket on what would be the rear, right side. It has an L-shaped bracket. I made one out of aluminum for a year or so, tell I found a GM one. The map has an elbow that comes out the bottom, and goes right into a vac port.... which your 85 wont have as you mentioned.

You can t some of that off, or I have seen people drill/tap the plenum for extra ports. Or a popular mod is to move the IAT sensor from the bottom of the plenum into the air stream, and then put a hose barb there for more vac ports.

I dont have car with me at moment, so I cant take pics. Will check in a min to see if one of my facebook pics shows it. :edit: nope, will have to take one for you later.

11-15-2012, 03:48 PM	#1913
Dale99 Registered User Join Date: Nov 2007 Location: NLR, AR Posts: 1,387	Re: PO has me PO'd My upper plenum is the correct for my year, 90-92, so it has a threaded boss for the bracket on what would be the rear, right side. It has an L-shaped bracket. I made one out of aluminum for a year or so, tell I found a GM one. The map has an elbow that comes out the bottom, and goes right into a vac port.... which your 85 wont have as you mentioned. You can t some of that off, or I have seen people drill/tap the plenum for extra ports. Or a popular mod is to move the IAT sensor from the bottom of the plenum into the air stream, and then put a hose barb there for more vac ports. I dont have car with me at moment, so I cant take pics. Will check in a min to see if one of my facebook pics shows it. :edit: nope, will have to take one for you later.