What you have in your diagram is not a great idea.

Yes it would work, but it places the turbo farther from the exhaust manifolds, and it won't spool as quick. You're better off getting rid of the crossover pipe connecting the two manifolds and having a pipe from each manifold meet at the turbo. Then, as you said, just plug the hole where the stock downpipe was.

What does the back manifold look like on a 3400? The exhaust would essentially have to flow backwards to where the crossover pipe was, and if the manifold is shaped more like a header instead of a log, it won't flow very well.

yes i also thought of the spooling aspect since its longer distance.... im going with the other way i mentioned...

and the back looks like the front exept there is an outlet hole that the downpipe is attached to. and the two are conected to the crossover pipe.... it would be more convenient if the downpipe camoe off the crossover but it doesnt lol

also some info on running the vacuum lines and boost controler will be greatly appreciated.

Update
 

i talked to a master tech today that owns a shop.. he used to do custom car setups specializing in exhaust and transmissions and other stuff.... on friday he will be making my manifolds and downpipe after hours at his shop... im pretty excied i will be ready to take it to milzy by no later than a week or two. he is doing it very very cheap because i refered him to my boss to send cars to from the dealership.....

oh and also this came in the mail today....;)

This is how mine is mounted



Old pic w/ turbo XS RFL BOV ^^^^^^^^^^^^^6


New pic w/ HKS SSQV BOV


Here is my downpipe pic.. i will say you will have to move the coolant lines to the heater core out of the way by cutting them and extending them longer out the way for the downpipe. My 2.5" piping barely fitted. The downpipe is in 3 sections connected by V-band flanges/clamps. It is really tight to snake back there for clearance.

My oil return line was custom made stainless hose at my local hose/fitting store. Its -10AN size. I would remove your oil pan and weld in a 1/2" NPT bung to the oil pan rather than your idea of drilling a hole and tapping the pan.

Just a question like that,dont we need pressure in the oil to cool the turbo??I mean,is there pressure in the oil pan during engine run?!?

The answer is yes, we need some oil pressure in the feed line, not so much to cool the turbo (which it will do some) but more so to keep the bearings and friction surfaces lubricated, which comes from a T-fitting off your oil pressure sensor for a feed line. Where they're talking about tapping the oil pan is for the return line from the turbo, so that the oil goes back into circulation.

Either way, don't tap/thread the oil pan itself. Get the proper bung, weld that in, then thread the fitting in, that way it is done correctly.

I gotta say, I can't make out much of the intricate detail work with this small of a pic, but from here, it looks beautiful man. I know it's not going to be a track runner, which is why the turbine housing is nearly up against the upper charge pipe (even with blanket). But as a trailer queen, it will work great. Nice job, looks great man.

i am having my downpipes and manifold pipes made tomorrow (steal of a deal btw). i will probably have pics of the turbo in the car with the inter cooler mounted on sunday...

the only things i am unsure about doing is; vacuum lines, oil lines , and the gauges(air to fuel, and boost)...as i have never done any of that before....

and aftermath it looks like you cut out a chunk of the metal bumper? what did you cut it with?

where do i purchace the neccessary stuff to do the oil return line?

i didn't cut anything metal in the bumper.. just the plastic impact beam.

thanks. Yea it wasn't a track runner, but I did run it on the track to see the times it did. I did pretty good at 13.9 in the 1/4 w/ all my stereo, 20" chrome heavy ass wheels.etc. Dyno'd at 250whp and 305 ft lbs on 6 psi. I would say those are pretty good numbers for an alero. Most people are amazed that its an alero to begin with.

hmmm that is plastic isnt it lol..

in my picture i posted of the bov is there a vac line that runs to it? or something
as stated before i have no previous experience with bov's or gauges

The blow off valve vacuum line simply runs to the throttle body or manifold (post throttle plate) so that it sees boost or vacuum just as the manifold does. So when you let off the throttle, there is a large amount of vacuum pulling through the vacuum hose and there is a large amount of boost pushing on the other side of the valve, making it open.

ok... will i have to install something to run it to from the bov? i see the bov has a nipple so im assuming i have to create one to go to?

Or just "tee" off an existing one. You'll have a ton to choose from. Mine goes right to one of the throttle body ones.

yes i noticed there are like three in that same location....
just to make sure im correct i T off one to go into the wastegate, and from the other part of the wastegate to the turbo end nipple... then one from the bov to the T on another vacuum line?

sound about right for vacuum lines? also can those T's be bought at a local store?

thanks for the help btw as im at the final stages it is much appreciated

ok so i know how to do the boost gauge, but which vacuum line would be best to T from? im using an internal v band wastegate... or which line would you guys recomend?

bu air to fuel im not sure about....

Only the manifold vacuum opens the BOV. The HKS SSQV is a pull type BOV. Boost pressure pushes on the back of the valve, holding it closed. It's one of the better BOVs you can get because it's impossible for it to leak.

so which line would you use?

Run a T off the line from the manifold to the fuel pressure regulator.