No boost
Thread Starter
Registered User
Joined: Sep 2016
Posts: 5
Likes: 0
No boost hey guys I'm new to the form, and I have a problem with my silverado. it's a 2010 4.8 and I just installed a race mmi twin turbo kit on it. the problem is that I can't get it to build more that 3.5 lbs of boost. it has no leaks within the system. the bov isn't leaking. they are internally wastegasted and the wastegates are set at 12psi right now. bother of the turbos are good, I had them both checked out by two different turbo shops in my area. it isn't an blockage in the exhaust because I disconnected the exhaust and that didn't help. it has stock injectors and fuel pump which I heard was good until about 8 psi. bother turbos are 50mm inducer, 76mm exducer
TECH Fanatic
Joined: Oct 2015
Posts: 1,280
Likes: 28
From: Pittsboro, IN
Ditch the stock injectors and fuel pump asap. Do you have any way to tune it? I would definitely upgrade the fuel system before trying to put any boost to it. If you are confident there are no leaks or restrictions I would make sure the wastegate actuators are adequately preloaded so they aren't opening too soon. Do you have a boost controller? How are the wastegate actuators plumbed?
