Boosted LM7???
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Joined: May 2017
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Boosted LM7??? Ima keep it simple.
Until I wanna drop the funds for a real build, I'm going to purchase an iron block 5.3 and throw a turbo at it with stock bottom.
Should I throw 317 or 243 heads on it?
I need the lower compression, of course, I just don't know what heads will benefit me the most.
Is there another head that I could use?
hoping for anywhere between 700-800 rwhp
This will be a drag car with some street use.
Until I wanna drop the funds for a real build, I'm going to purchase an iron block 5.3 and throw a turbo at it with stock bottom.
Should I throw 317 or 243 heads on it?
I need the lower compression, of course, I just don't know what heads will benefit me the most.
Is there another head that I could use?
hoping for anywhere between 700-800 rwhp
This will be a drag car with some street use.
I'm putting 4.8L flat tops in a LM7 with 317's.
With a .040" head gasket should get me right around 9.5-9.6 compression.
I wouldn't go any lower than that.
317's on a dished 5.3 piston is like 8.6 compression which is no bueno lol.
With a .040" head gasket should get me right around 9.5-9.6 compression.
I wouldn't go any lower than that.
317's on a dished 5.3 piston is like 8.6 compression which is no bueno lol.
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Joined: May 2017
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Never mind lol
No worries lol, if you haven't purchased any heads I'd roll with 243's.
I've been told by a reliable source they flow better and have better chambers than 317's.
I'm only using 317's because I have them and they're CNC ported by a guy who trained at SAM.
With 243's you'll be low 9:1 compression making your tuning window bigger and more boost on pump swill to help you get to that 700whp mark.
I am no expert by any means and I'd suggest reaching out to someone like John Bewley at LJMS for his experience and one of his cams lol.
I've been told by a reliable source they flow better and have better chambers than 317's.
I'm only using 317's because I have them and they're CNC ported by a guy who trained at SAM.
With 243's you'll be low 9:1 compression making your tuning window bigger and more boost on pump swill to help you get to that 700whp mark.
I am no expert by any means and I'd suggest reaching out to someone like John Bewley at LJMS for his experience and one of his cams lol.
