[east TX Muscle cars]

Originally Posted by Dinky Toy

I have never owned a FI engine so I am no expert and you are free to call bullshit on my method of thinking if I am completely wrong, but...

"PRESSURE IS PRESSURE", that is true, but when talking turbo lag you are talking how quickly pressure is build up and that is a different story.

"If you pressurize a tube 2 inches long versus 24 inches long it doesn't matter.", that is true for fluids which are "non-compressable" but when talking about air which is compressable please consider that volume matters and a longer tube equals more volume.

At the end of the longer pipe is the turbo which is a restrictor (however marginal), therefore when pressing the throtle you will have the engine moving more exhaust air into the pipe towards the turbo.
Yes the turbo will start to spool faster instantly BUT since the turbo is a resrictor, the pressure in the longer tube in front of the turbo will build up and the extra volume of the pipe will require more energy and time to get to the full pressure the engine can generate and therefore the turbo to spool at the maximum RPM with that maximum pressure from the engine.

Something similar could be said for the extra length pipe back to the intake manifold since the engine is a restrictor too (hence the neccesity of a waste gate).

Now, whether the extra "turbo lag" from the longer tubes (both ways) creates noticable differences I will let someone else proof.
All other components kept the same, negatives of remote mount are probably offset by higher temperatures and need for intercooling when using under the hood turbo systems.

It is a very valid point. Volume is most definately a factor when properly setting up a remote mount system. A lot of time goes into selecting the tubing sizes and turbo sizes. You have to take into account velocity of exhaust and the velocity of air from the turbos. Then there are the temperatures of the air returning to the intake and so on. I can assure you that when Rick (sts turbo systems) engineers a system he does all the math for it before just throwing it on a car.