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243 head on 5.3 question (sorry)

Old Feb 29, 2016 | 08:21 AM
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Default 243 head on 5.3 question (sorry)

I want to put a set of 243's on my 5.3 the truck is a 2000, I had people tell me I need to mill them down to keep my compression the same, but will that make the intake fit wrong? I'm sorry if I'm miss interpreting this wrong, I plan on running a tbss intake, and is a lot to get them milled? Also could I just replace my Pistons with 4.8 pistons and keep my compression with out milling??
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Old Feb 29, 2016 | 08:35 AM
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Yes you could use 4.8 flat tops. Milling the heads shouldnt be too much of a problem unless you go too far. I forget how much you need to shave them down to keep compression the same...
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Old Feb 29, 2016 | 09:54 AM
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Ok I think I'm just gunna use the flat tops cause I know you ha e to mill like .030 off I think, and I'm not sure how much that would be, I can prolly get flats tops cheaper than milling
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Old Feb 29, 2016 | 10:13 AM
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For all that work just find a gen4 5.3
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Old Feb 29, 2016 | 10:16 AM
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If I'm gunna by a motor I would just buy a 6.0 but I'm gunna work with what I got for now, I have access to all these parts fairly cheap
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Old Feb 29, 2016 | 10:21 AM
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The cost of labor
Cost of balancing rotating assembly
Cost of bearings
Cost of 243s


Come in pricer then a full motor
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Old Feb 29, 2016 | 10:39 AM
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Well I didn't think about that stuff this is my first build and I'm just trying to work with what I have, my original plan was to build a lq4 but I figured I would just build what I have, maybe I just need to throw the heads on and not worry about the compression, cause I am doin a cam (not sure what to run) tbss intake and I would like to run 243s, like I said maybe I won't worry about the compression then, I didn't know that all went into that, and again don't bash me to hard it's my first build, there's some things I just don't know, and trust me I ask a ton of questions and I wouldnt just throw this together, I want to do it right
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Old Feb 29, 2016 | 10:45 AM
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Cut the heads .030 and toss them on..should bring you close to compression you were stock

Look to spend 100-250 to have heads cut, so add in cost of head gaskets..80...add in cost of head bolts if using stock 65....cost of heads 200-500...add in cost of springs 250.....add in push rods 100....add in cost of cam 375


Are you ready to go down this road
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Old Feb 29, 2016 | 10:56 AM
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Ok thank you and I'm sorry if this is a dumb question but will there be any intake fitment issues? Thank you George for you patience and I'm sure you will see more of me on here
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Old Feb 29, 2016 | 10:57 AM
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Yes I have been doin supporting mods for a cam, long tubes, bigger fuel pump, bigger injectors
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