97VetteDan

How do you install the plenum without loosening the runners at the intake on a 1990 Corvette?

WW7

On my 89 when I loosen the top runner to plenum bolts the runners expand out enough for me to just slide the plenum out. To put it back in I just slide it back in and tighten it back up. I don't know if all the runners out there open up enough to do this. but Im sure glad mine do.....If yours is so tight you can't do this, the only thing you can do is loosen up one side of the runners at the bottom...WW

neverendingprojects

I'm lost with this whole idea, why not just crack the lower runner bolts loose... Its not that hard, plus you wont have to use a pry bar to get the plenum back in....

Dads90

Well, if I remember correctly there are a couple of torx head bolts that are only accessible from the backside. That means they are blocked by other engine components. Once the upper bolts are removed I just tapped on it with a rubber mallet and it pulled up. Plus make sure all the hoses and tubes are disconnected.

oldalaskaman

on my 87, I tightened the bottom up, inside and out, and when I slid the plenum in there was enough room to get it and the gaskets in with out issues. something you might try is to use a large flat tip screwdriver and gently slide it in , there's some give

WW7

I didn't think mine was the only one that would work this way and allow me to just slide the plenum into place without loosening the runners.I see there are quite a few others. If you look at the plenum you will see it is cut at an angle (like a wedge) instead of straight up and down, to allow you to slide the plenum in..Just don't use any type of adhesive on the gaskets or you can't get them in without them sticking and screwing up.....WW

impact1968

Mine spreads apart at the top also, without loosening the lower bolts.