Will a twin exchaust sytem of 2.5 inch each (2 pipes - one for each block of cylinders without the X pipe - just the true twin system) be enough for a VG30DETT running 25psi to run to its full potential or is it essential to run 3 inch system for each block of cylinders? PS the car is not a Z32 and hence no X pipe... the system is going to be completely custom made - just thinking if I could use the mufflers that I really like which only ocme out in 2.5 inch inlet sizing...
Depends on the setup if you were trying to squeeze 25psi from stock turbos through stock manifolds, stock heads etc then there would be no point upgrading to 3 inch dual If you had a built car with extrude hones manis bigger turbos etc or use the car on the trac ketc where boost is always on then 3 inch would work Need more info
The engine will be stock internally for a while, but the turbos , injectors, ecu, manifolds will be all aftermarket - with the intention to use the car on the track mostly... I would have thought twin 2.5 will still be more eficient than a single 3 inch like GTR boys are running and seeem to be doing fine even when pushing high hp...
