so i read up about the inlet butterflies on the CA18DET, they reduce the inlet flow up to roughly 4200rpm to get better torque/power/flow below that point. above that they can be open for high flow/power

people have shown on the dyno 15kw extra power (at an rpm where you have 60kw) and 15-20% more torque below the switch point of 4200rpm

thought i would try hooking mine up with the suggested vac pump method. previously mine was just connected to the inlet manifold (this gives the benefit off boost - but with the T25 boosting at like 2500rpm im missing the benefit from 2500-4200) even with a bigger turbo the butterflies should also assist with getting on boost earlier

anyway it worked and works great, i now have more power when it first comes on boost and i have noticed the asthmatic sound i could hear especially in 3d/4th gear is gone, there is just more power and smoother delivery

so.... it's not meant to be a sales pitch... but i got excited at the wreckers... i left with 6 of these pumps when i only wanted 2... so if anyone wants one get in contact... otherwise i pulled them from volvos/audis A4+A6/saabs with cruise control... they were all in different places such as in the passenger guard behind the water tanks and under ABS controllers, one was conveniently on a firewall. I will post a pic of the pump and wiring instructions if there is interest

by using the elec pump you dont need the valves/solenoids and reservoirs of the standard CA setup, so it's a bit neater and hopefully more reliable

i watched the pump activate the butterflies, it has a nice smooth action over 1/2-3/4 of a second so i dont think a valve is required to smooth the action

I'll take one thanls

I'll take one too. how do you Hook them up..?

basically you need a to be able to wire a relay for them and then the one vacuum hose from pump to the butterfly diaphram

i got a diagram for the relay off the net which i will post but there was an error in another diagram for the wiring to the pump itself. the wiring is a little tricky because it's all earth triggered but if you follow the diagram there should be no problem

$45 delivered for a pump, you will need your own relay

looks neater and goes better sounds good!

Sounds interesting. I'm keen to see a pic of these pumps to understand how big they are and where I can neatly locate one.

Went to local wreckers yesterday for some radiator brackets and was looking under the bonnets of a few Saabs and Volvos. I located something that I think is what your a talking about. It had 2 x Vacuum connections with 1 going to the inlet manifold and the other into the air intake line and also had a couple of wires going to it.
The vacuum pipes were a fair size (like heater hose pipe). If this is what you have I'm curious to see how you plumb it in.