4.8 stock bottom end 600hp
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Teching In
Joined: Jan 2017
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4.8 stock bottom end 600hp I have a 4.8 in a 04 sierra reg cab short bed. I took the motor apart last summer and cleaned up everything. While it was tore down I threw some 243 heads with some blue springs on it. Also put a boost cam with mid to high range power. I'm already in the works of getting a turbo, injectors,and fuel pump upgrade. I'm just wandering what kind of power this setup will yield and what else I would need to make around 600hp if what I have isn't enough. Thanks in advance open to anything I'm still learning myself
Are those spring capable of handling your boost cams lift? You'll need a decent amount of boost to make 600rwhp assuming through an auto on a 4.8, but a good turbo and time should get you there.
I'd recommend more spring than that on that small motor. I have Comp 918s on my 317s with an LS6 cam in my Gen 3 4.8 (spun a bearing), and ran up to 17psi on 91 octane alone because of the low compression. It was probably only making 500rwhp, but a gen IV with pump/meth could easily break 600rwhp in the 20psi range if properly tuned, but I'd recommend more spring pressure, because these little 4.8s like to rev (mine loved 7200).
On my previous Gen IV 4.8, I was making 760 on 16psi from a 78/76, granted that was through a M6, but with the right setup you can absolutely make good power. I've since gone to a Gen III (old one spun a bearing) and a TH400 so I'm sure i'm making a good bit less, but don't discredit the potential of the little 4.8, just have to make sure your setup is moving air!
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From: Pittsboro, IN
