by dieselguy86 » Mon Aug 06, 2018 11:45 am
Im doing this right now, its all about how much power you want. Simply adding another turbo to a diesel wont give you extra power, you need extra fuel with that extra air. You can have a very well-mannered engine with a single turbo up to around 200-220hp. After that youll either have to deal with smoke with a smaller turbo, a big single turbo that will lack low-end torque, or compounds.
On my 250hp build i need 38psi (2.6 bar) to have a smoke free air:fuel ratio of 25:1. 38psi of boost is pushing a turbo past its efficiency limits. So its easier to “split the load” to 2 turbos. The secret is getting them to each do half the work, and not have one turbo doing more work than the other.
But now you also have alot more plumbing, not only oil feed/drain lines but the exhaust and boost plumbing. Then your going to need to upgrade your intercooler because your going to have 300+°f (149+°c) air coming out of the second turbo.
Not trying to scare you away, just trying to shed some light on what all is required to not only add another turbo, but what it takes to build a PROPER system.
-Joe