Originally Posted by Kodiak450r
i guess something right in the middle of the 2. I'm not looking to rotate the earth, just pick up some extra HP. This is budget minded as well. I know i will have to spend some money on fueling and computer tuning to make it all work. So i really don't wanna spend up to 2000 on just a turbo from garrett or turbonetics.
Budget minded and turbos don't really fit in a sentence. I'm going to assume you mean this relative to what is necessary for a turbo setup.
Not that I can answer your question, but pose some others for thought:
1. What is your desired Initial compression ratio (static and/or dynamic)?
2. What you want to run for fuel and how you will fuel it?
3. How much are you really looking to spend?
4. What are your aspirations on power?
It is worth looking around on the diesel sites (Cummins forum and competition diesel for example) about how to understand the turbo maps wheel sizing, a/r, etc. Once you really set some parameters there are plenty of people that know way too much about turbos there. There are some really good write ups on choosing a turbo. It should be applicable to gas motors (with the right changes in calculations. I doubt you are going to try to build a 16:1 motor)
One other possible route is to look for two smaller turnouts like you said. if you could find an oem application that uses similar rpm ranges, motor volume and psi for your goal (so for example, two 2.5l motor turbos that make 6 psi with a redline of 6500 rpm in a 5.0L setup), you might be able to make something work.
You could also try a oe turbo off of a diesel, say off of a early dodge, but it might make your motor laggy? I'm not sure what the differences in rpm would do for the motor or displacement of air/fuel.
I realize I did not add much to the discussion...