brandonbartlett18

I do not have a lot of knoledge of the turbo systems but i have been doing as much research over the last few months as i can. Please correct me if i say something stupid.

I have a 2001 chevy silverado with a 4.8 vortec. From my research i have decided that about 7-8 pounds should be safe on a stock engine. (I plan on upgrading engine components later in order to withstand more boost.) However in order to get started on my addiction for speed i have devided to start small and work my way up.

I want to start with an evo III 16g turbo. From what i understand it spools pretty fast and is plenty for 8pounds. I am plenty capable of fabing and welding everything up in order to make it fit and bolt up.However i have 4.8 litres of displacement... lots of exhaust. Since i only want to boost to 8 , will the internal wastegate in these turbos be able too keep up with this larger engine or am i going to get a lot of turbo pressure creep.

So what do i need to do in order to run this turbo on a 4.8 vortec? Will the internal wastegate be plenty to keep the boost down? Do i need to weld the flapper shut in order to disable the internal wastegat and switch to an external wastegate and fab something up in order to move more exhaust around the turbo? This might be a stupid question but can i keep the internal wastegat functional AND add an external wastegate? Could i just run the pressure lines to both wastegates so they both open when boost begins to get to high?

Like i said im new to the turbo comunity so feel free to tell me im stupid. I dont get butt hurt. Any help and advise helps and gets me closer to completeing my research. Thank you.

Matt Cramer

To run that turbo on a 4.8, use two of them. One of them won't keep up with either the exhaust or the air flow needs of a motor that makes as much power naturally aspirated as an EVO III does with a turbo.