3" SPD Downpipes + Stage 5 turbo upgrade questions

[F=MA]

So I have the Whipple Intercooler, ZFG E50 tune, and Borla S-type exhaust. I assume if I purchase the 3" SPD downpipes wouldn't it make sense to also install the upgraded Stage 5 turbo upgrades at the same time (since they are connected together). So answer me this:

1a) What is the net gain in horsepower by adding both the 3" SPD downpipes and the upgraded Stage 5 turbo upgrades yet keeping the Borla S-type exhaust.

1b) Will adding the 3" SPD downpipes and/or the upgraded Stage 5 turbos create a new drone in the otherwise stock Borla S-type exhaust system.

2) What is the net gain in horsepower by adding both the 3" SPD downpipes and the upgraded Stage 5 turbo upgrades and installing an electric exhaust cutoff (right after the downpipes) to bypass the Borla S-type exhaust.

3) What is the net gain in horsepower by adding both the 3" SPD downpipes, adding the upgraded Stage 5 turbo upgrades and adding a custom 3 inch exhaust system.

 

[zdubyadubya]

I'm going to preface this by saying I don't have any hard hp numbers to back any of this up BUT I would recommend the following:

A turbo engine needs to breathe freely both incoming and outgoing in order to maximize efficiency and power. Upgrading turbos or downpipes without also addressing the Borla exhaust would be "choking" your upgrading turbos. This is coming from someone with a Borla ATAK. Its a good system--IMO makes the truck sound MUCH better--but its just that, sound. There is no performance gain there.

First address exhaust, then intake, then fueling, then tuning.

Your first upgrades to your existing system need to be downpipes and a 3" system to go with them. Speaking from experience, you will never use a cutout system unless at the track--how often do you truly see yourself going to the dragstrip.... They get REALLY annoying and REALLY old quite fast. Loud is fun for about 5 minutes. And its not a pleasant loud like an F1 car... its just loud.

After exhaust then you will want to go with a new fuel pump to prepare your engine for the stage 5 turbo setup.

According to ZFG, the intake system on these trucks is pretty sorted and you have already upgraded the intercooler. So you can check that off.

Once exhaust, intake, and fueling are addressed, then you can go ahead and slap on your turbo kit and tune to your heart's content. Otherwise, at any of above steps, you are creating your own bottlenecks and the stage 5 is a waste of money and potential.