Is there any way to eliminate the air pump while till having the the 5th and 6th ports still operational? will you tell me the steps?

 

Your profile says you have a 91, the S5 6pi needs the airpump to work. You could use a 12v airmotor, but that involves wiring, air line routing, buying a rpm switch blah blah blah. If yours works, leave it be.

Why do you want to remove the airpump anyway? It doesnt gain/free up you any horse power.

 

the air pump controls 5th 6th ports and VDI on a s5 89-91, removing it isnt worth the gain ( less than 1 hp). and usign an electric pump to triger them draws power, which puts stress on the alternator, which takes away HP when ti works harder....

 

A more detailed question:

Underdrive pulleys; will an UD crank pulley cause the ports to open at a higher engine speed? In theory, the air pump will spin slower per revolution; ergo the vacum or whatever magical force that opens the actuators doesn't build adequate pressure until higher RPMs are reached. Is this logic correct? If so, what are ways around it so that the ports open at the proper engine speed?

Headers & a pretty much straight-thru exhaust; what impact does a drop in back pressure have on the 5th & 6th ports? If the consequences are negative (ie; they don't open or open at later engine speeds), what can be done to remedy this situation that doesn't add too much weight or require a special machined 'overdrive' pulley for the air pump?

Running the actuators off of vacum seems to be a big PITA when stuff starts changing, has anyone converted/adapted electronic actuators to open the OE ones? If electric, I see it being possible for them to work via a module that would be similar to a shift-light or any other tach-sensitive module.

I'm asking for a N/A S5 and just wiring the ports open isn't an option.

 

So no one yet has converted their OE actuators to electric or a servo system? I've read stuff on here about using other air pumps & other over-complicated ****, but that's all.

(Brainstorm) If a rigid, yet simple, bracket was fab'd/modified to support a small electric actuator or servo - why couldn't that be able to open the 5th & 6th ports at the same time (or just use 2 electric actuators/servos)? An el'cheapo shift light, which has to ability to turn on a light at & above a certain RPM and off when lower than the set RPM, could be used to trigger a relay to send current to extend & retract the new electric actuator or servo. Relays don't go bad, a shift light is pretty darn simple so I can't imagine that taking a crap, and the assortment of actuators on the market is quite extensive if you look in the right places...reliability from the electric actuator would be my concern with heat/moisture/engine funk, so I guess you'd need a pretty bullet-proof product. I'm not as familiar with what sorts of servos are out there - but I'm sure someone makes something.

This is all theory until my shop manual arrives (I don't want to deal w/ *.pdf crap), but has anyone else thought of something like this, or better yet tried it?