just asking for peoples theories on this.

Thanks

 

Advantages
1) Simplicity. After removing all the stuff, you have a much cleaner engine bay, with only a handfull of vacuum lines. So if something goes wrong, its an easy diagnosis and fix.
2) Weight reduction. Not much, but maybe 30lbs, most of which is from the air pump.


Disadantages
1) Well, its illegal, and if you have emissions testing, you cant do it anyway.

 

1.Will this improve or harm fuel efficency?

2. What if rather then totally removing the pump I just removed the belt?

 

1) I wouldnt think it would have much of an effect on fuel efficiency at all. I would suspect that it may harm it slightly, but doubtfull that it would even be noticable

2)Why? Keep in mind that you need an air pump for the catalytic converter to operate properly. So if you still have a cat, you do not want to do this, as it will burn up. Also, if you have a S5 (89-91) car, this pump is needed for the operation of the aux ports on N/A models. The pump really isnt all that much of a drag, so removing the belt wouldnt be noticable power-wise.