So my oil metering pump hose broke and I'm replacing it. When taking everything a part I noticed that the vacuum line was hooked up for the front housing but not on the rear housing. The line was capped so I know this was done on purpose. Should I hook both of them back up or leave the rear one off. Is there advantages or disadvantages?

I guess I should mention this car has been converted to single turbo.

 

i would have both the same. hooked up or not is up to you. stock goes in front of the turbo, if i'm not mistaken, and i've seen single turbo cars that didn't like this (smoked at idle), so you cap em, or put a filter on it or something.

 

The oil injectors just need a fresh air source. I like to use the little filters from the sequential solenoids and put them on with a short piece of silicone hose.

 

Yep. Stock the vacuum lines to the OMP just go to the primary turbo inlet duct, which is just a source of filtered atmospheric pressure air. No, it's not under a vacuum - if it ever is, it's a VERY small vacuum, like less than 1".

Ihor is right, easy way is to just put little filters on them, you can steal them off the stock solenoids.

Dale