quick general turbo questions

[amimaxima]

I was wondering about a few things, maybe you guys can help me out here.

oil drain : what is some of the easiest ways to do this?
from what i've read you have to drain the oil into an unpressurized location.

external wastegate dumptube : which would be better running the dumptube from the wastegate into the downpipe for the turbo or just having the wastegate dump into the atmosphere with say a 24 inch downpipe.

wastegate springs : I know what "bar" means but in relations to what does the w/g spring have to do with? so I want to boost 10 psi into the engine what spring would the w/g need?

[homemade wrx]

the easiest return for oil is normally tapping high in in the oil pan...
dumptubes are easier to make and prevent power loss causing turbulence downstream of the turbo..hinders flow and loses power...just go atmosphere...
for the wastegate, what do you plan to run for a boost controller? if you want 10psi I would run a lighter spring and use a boost controller as you have room to play and turn down boost incase of a bad tank of gas...
1 bar is 14.5 psi incase you were asking...

[amimaxima]

alright i'll run the oil drain high on the oil pan

use a long dump tube and dump it into the atmosphere

plan on running 10psi after the tune. so with what you said about the spring for the w/g should I run a 5psi or a 7psi spring and then conrol it with the ebc?

[homemade wrx]

I'd just run a 5psi...you can get a 3psi spring to hold to 22-23...so you will be fine

[amimaxima]

alright I found out that the motor can handle 5-7psi

should I ran a .4 bar spring which is 5.80 psi or should I go with a smaller spring?

[homemade wrx]

you can do that...but then you have no margin of safety to detune to lower pressure if needed...

[amimaxima]

so what spring should i use?

[homemade wrx]

what wastegate are you running?...guessing tial or turbosmart 38mm...?

they have them ranging from 3.5'ish psi on up...so run the smallest one and use a boost controller for any level of boost over that :D

[amimaxima]

a tial 38mm F38

[Alex01tib]

I agree, go with the 3psi spring, itll leave you room to go down if your fuel cant handle 5-7 and will give you the ability to fine tune.

Oil return can be in the oil pan, just make sure its above the full oil level or else it will cause draining problems.

Alot of people swear by the block return, but i dont like the idea of drilling a hole in my block, although this way makes leaking improbable even without weld.

Unless you plan on running a huge amount of boost, you wont see any losses in turbulence in routing the wastegate gasses. The extra amount of noise with a wastegate dump isnt the most appealing sound & may not be your cup of tea, and it may get some "unwanted attention"

[homemade wrx]

true, if you motor (I'm unfamilir with it) has an opening or a plug that runs to the crank case, run that as it will be better and safer than the oil pan. For my subie customers (kinda my thing ;) ) I had always done the oil return through the head.

[amimaxima]

i got a tial f38 today with a .4 spring. i also bought a hks ssqv and a t3/t/4 oil feed and return kit

[manifoldmike]

instead of tapping the pan, i would weld a bung on it. less suseptable to leaking. doesn't really matter if the return is under the oil level, you just need some line for the frothy oil coming out of the turbo to settle down and drain into.

dump tube length doesn't really matter, just dump it under the car away from the intake.

i personally wouldn't run less then a 5 psi spring. 5 psi = fart in wind.

you always want to put your spring at what your going to actually run. most people say "go low, so you can turn it down." two problems with this, 1) you will never turn it down. its a disease 2) if you can turn it down, you can also turn it up, which will get you into trouble.

run a spring with no controller, that way you won't toast your rings, blow the welds on your intake and have floor boards fall out.