3.4L -> 2.8L Accessories; air pump, water pump.

[Canyonero]

I'm mix and matching parts on my Trooper when I install a Crane Cam and 3.1L intake. In the process I'm going to switch back to the 2.8L accessory mounts (so I can move the battery back to the engine bay and reinstall A/C). But my 3.4L doesn't have an air pump and my old 2.8L did. What should I do about it? I don't have any wiring or threads on the manifold for it anymore.

Looks like the 3.4L exhaust manifold still has a boss in the casting for it, so I could drill and tap a new hole. Or should I just leave it in place but disconnected? I think I still need it for belt routing, unless I want to fab an idler pully to go there.

Is the water pump rotation the same?

2.8L w/ Trooper mounts:

[Canyonero]

Water pump rotation is the same. I think it was backwards on S10s or Jeeps or something, but it's fine here.

[geoffinbc]

Only V belt engines have standard rotation pumps. All of the serp belt setups were reverse rotation. But the Camaro and S-10/Trooper pump are different. The S-10/Trooper pump has a longer shaft and casting snout to support the clutch fan. The Camaro pump is designed for use with an electric pump.

[Canyonero]

Thank you. I'm using an electric fan, so I'll stick with the shorter pump.

[Canyonero]

Ok, good news. I took a look at the 2.8L brackets, looks like everything will still be properly supported if the air pump is removed. I'll need to get a shorter belt, but it looks like the belt tensioner will still work as-is.

I mocked up the 3.1L intake on a 2.8L. Looks like I'll have to cut off the throttle body neck to get it to clear, but that's ok. Little TIG welding and it'll be better than new. I might have my choice of mounting that way too.

[geoffinbc]

No I tried it. The tensioner will not work without the air pump pulley there. I tried about 4 different belt lengths to try and make it work. You need an idler or keep the pump. The idler could be any size though.

[Canyonero]

Just can't get adequate tension? I'll see what I can figure out.

Nice to have another block to set this up on, hopefully I'll be able to do to conversion is a reasonable time frame. I want my A/C back by next summer. And my battery out of the cargo area soon as I can.

[geoffinbc]

Exactly the tensioner was acting on the belt that would basically be making a right angle turn around the tensioner instead of a full 180* wrap. It would just bottom out. I used a belt that had to be pried on with a screwdriver and when I released the tensioner it bottomed out. Factor in a little stretch after run in and you would have a loose belt in a matter of a couple hours.

[Canyonero]

Want an air pump bypass bracket/pulley if make some?

[geoffinbc]

Well I would but only if they were free since I have a machine shop to do it in LOL.

I don't mind keeping the pump anyway. It does not use any power and if it does in fact help the cat converter light faster then I am all for it. I would rather not shorten the life of the cat. I did ponder the idea of converting to an electric AIR system like the camaro's and second gen S-10's had. The same relay control that opens and closes the valve on the belt driven AIR pump could be used to control an electric pump.

[Canyonero]

Well maybe you should make ME one. :P

Did my 3.4L have an electric air pump? I also wouldn't mind keeping it if it improves emissions. I don't have a cat right now, but I'm going to have one put on. I don't recall seeing any air pump wiring, but I could have missed it. There aren't any ports on my exhaust manifolds to hook one up either.

[geoffinbc]

It would go right into the cat or just up stream of it. I have never seen where the Camaro pump enters the system. My Brother S-10 has one.