Outer Limits 4x4 Board

what makes the roaring down spool noise on cruiser and patrol 6 cylender engines?

i have mates with patrols, identical TD42's and one is silent compared to the other, both big exhausts and no mufflers but different turbo kits

i also know of 80 series cruisers with the same squeal sound, wondering if anyone knows what it is.
intercoolers or piping change it at all?
wastegate designs?

i also drive a heavily modified petrol turbo engine in my other car with the same sound, but it "chops" and isnt constant like the diesels (if that makes any sense?)

i know on my engine, it is the piping from the compressor housing to the air filter, if i change that from a bend to a straight pipe, i can make it almost silent, wondering if the diesels are the same

here we go again

http://www.outerlimits4x4.com/ftopic159294.php

Jacked wrote:here we go again

http://www.outerlimits4x4.com/ftopic159294.php

BWAHAHAHAHAHAHA

yes that is a thread on the same sort of topic, it still explains nothing though, and i wasn't asking about turbo whistle, or even that i am trying to make noise or whatever, i dont even own a turbo diesel.

obviously they dont do it stock, and one particular modification will change the noise, i was just asking a curious question

so anyone with experience?

it has to do with length of pipeing, blow off valves or not, type of airfilter, type of turbo, coolers. some do it stock some dont.

1 car is cooler than the other