Hello..



I am replacing my water pump on a 91 vert and I got a new pulley that doesn't allow for the air pump to be used. I am trying to find out if the air pump is really neccessary. I have heard conflicting reports so maybe someone who has removed theirs can tell me.



Thanks

Someone tell me if I'm wrong, but I believe the 5&6th port actuators on a '91 are run by the air pump.(non-turbo) The early models ('86-87) are run by air fron the exhaust. There was a thread on this forum or the other large forum about taking the air pump off and still running the actuators.

not sure about the ports, but you will have to remove the catalytic converter, if you don't it will clog up

and also keep this out of gen d

You don't have to hollow out the cats, and the air pump apparently isn't what opens up the 5th and 6th ports. However, there is a pipe that runs back to your catalytic converters. If you leave that on, then the ports should open just fine. I took mine off, and so now I have to wire them open, which is really easy, so basically no, you don't need the air pump. :bigthumg:

Thank you to all who have helped but I am still confused, I seem to get different responses - So if any one has a real good idea of this I would be very grateful as I do not want to ruin anything car is 91 vert non turbo automatic



thanks

You can remove it especially if you put a header on. The headers that are available don't compensate for the air pump. If you take it off wire the ports open and take out the cats because they will burn up very fast. As long as don't have to get it smogged your cool. If you do you have to keep the air pump on, California smog rules suck.

Ok wiring the ports open makes you oose low end tourqe and you gain nothing unlees your ports where not functioning properly. In the s5 the 5th and 6th ports ARE operated with the air pump. Your catalitic converters will eventually get clogged if you remove the air pump so unless you have another way to make your ports work properly I would suggets not taking it off. you mentioned that the pully you have on the new water pump does not allow you to keep the air pump? What water pump are yo uunsing and how come it has a different pully on it.



87rx7na the reason the air pump is not what opens the ports in our cars is because we have series four FC's he has a 91vert that is a series five which ses the air pump opposed to our cars which use back presure from the exhaust.

oh I forgot that if you do happen to remove the air pump which I do not recommend because you would have to wire oppen the 5th 6th ports thus loosing their puction which provides tourqe down low and hp up high you will have to buy a dual belt alternater pully so your water pump opperates properly. :bigthumg: