Good Lord this thing got big overnight.
Again, no offense Wes, but (1) Custom piping is a huge undertaking. Now, if you're going non-aftercooled like AGM, then it's considerably less, but still time-consuming. Once one is made and all the interference issues related to the different models/trim levels is verified, you can make a jig & reproduce them at a reasonable cost.
(2) A mandrel bending machine (real one) is about $180,000-$250,000 with the fixtures required to do all the different possible piping diameters. (pricing reference from Dave at BentPipes.com who owns one)
You couldn't pay me to run an ATI (Procharger) or Powerdyne unit. Vortech/Paxton is now.....well....Vortech/Paxton. Same company albeit slightly different designs between the two.
Not in a million years would I run a self contained centrifugal charger. They stew in their own juices & run hot as a sum*****. The oil fed Vortech/Paxtons have much much longer intervals between rebuilds. ATI is a race blower, frequent rebuilds are expected. The only benefit of a self contained unit is a shorter installation time on account of the oil return line's requirement that it be plumbed into the oil pan.
For those not familiar, a "T" fitting is installed on the engine oil feed system that uses oil pressure from the engine and air pressure from the charger to force feed a mist of oil spray on the bearings inside the supercharger. Once it goes through the cycle, it drains towards the bottom of the charger & must be returned into the oiling system via the pan, NOTE: the return should be placed above the windage line on the pan, (above the oil level line when the engine is running). Otherwise the return oil can back up in the return line and cause problems inside the charger.
A standard FMU from Vortech, Paxton, etc *does* have issues when boost drops. They're great on the way up but when you shift they don't reduce the ratio of increased line pressure resulting in a horrid bog. Also, as Q45Tech mentioned, there's a pressure relief valve in the pump that won't allow more than 60 psi fuel rail pressure. That's good for maybe 4-6psi. (SWAG)
The Super FMU from Vortech is a bit better between shifts, Comptech also has a beautiful billet one. By the time you buy either of them, you're 1/2 way to a JWT boost program. Much better driveability and performance at all rpms, loads, boost levels. Always better if the car thinks it *came* with boost, like the JWT.
Hope that helps, I started this this morning & just now was able to finish it.
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