Outer Limits 4x4 Board

Hello fellas ,I have heard a few gu turbo diesels getting around with a big exhaust on and you can really hear the turbo spool up,they sound like bloody trucks.Does any know if this is just exhaust and if so what size .Or is it turbo upgrade?Any help would be appreciated.
Thanks Marty

try some searches...... 3" exaust, some pre made ones available or go to a truck exaust mab and they can make one up, can do a bit of work to the turbo as well, go to a diesel place up your way and they can tell you all about it