Anyone know what size this hole is? I'm trying to plug this thing off and I can't seem to find the right size plug or even bolt

Can anyone verify if some of these cars came w/o air pumps so that the manifolds wouldnt have this hole? 2.8,3.1, or 3.4's? And if so, anyone got one to sell a friend?

 

My 92 3.1L doesn't have them, but i have heard of other 92 3.1 that do have them. I haven't found any ryme or reason to determine witch came with ot with out air holes in the manifolds.

 

whay are you blocking it off. You know that it only pulls like 1/4 HP right???

 

Thanks, I went and installed another pipe plug in the hole that doesnt have correct threads.

Time to start looking for a better manifold.

 

Look for a manifold from a '89 w/o air. Also grab the idler spider from it. The idler setup will prevent the belt from slapping along the long open path (alternator to the crank pully). Can use a stock '89 serpentine belt too.

As for your original question the hole/threads are not a standard size. I actually made a nice brass plug for it but alas it keeps coming loose (just like the stock tube nut always did).

RBob.