LQ4 Build, milling 317s
02-19-2011, 10:20 AM
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LQ4 Build, milling 317s Picked up a low miles lq4 yesterday, so far just have the intake off. But I pulled a valve cover and man does it look clean, like brand new, theres marks from a paint marker on the inside of the valve cover, on all the springs, and the inside of the head, looks promising!
Will be running stock bottom end.
I want to use the 317s as I can get them milled for nothing, literally. My question is how much to mill these guys?
Stock for stock, they flow the same numbers as 243/799 castings, or so im told, but with bigger chambers. The 317s have 72cc chambers, where the 243/799s have 64cc chambers. Obviously I want to get them as close to 64 as possible, but thats just not happening. If I use the math that .007 milled is 1cc, then to get to 64cc id have to mill .050+, just not possible.
But if I mill to much im going to kill my valve clearance.
Trying to get this figured out asap, id like to get the heads to the shop today if I can.
Will be running stock bottom end.
I want to use the 317s as I can get them milled for nothing, literally. My question is how much to mill these guys?
Stock for stock, they flow the same numbers as 243/799 castings, or so im told, but with bigger chambers. The 317s have 72cc chambers, where the 243/799s have 64cc chambers. Obviously I want to get them as close to 64 as possible, but thats just not happening. If I use the math that .007 milled is 1cc, then to get to 64cc id have to mill .050+, just not possible.
But if I mill to much im going to kill my valve clearance.
Trying to get this figured out asap, id like to get the heads to the shop today if I can.
02-19-2011, 12:06 PM
#2
Picked up a low miles lq4 yesterday, so far just have the intake off. But I pulled a valve cover and man does it look clean, like brand new, theres marks from a paint marker on the inside of the valve cover, on all the springs, and the inside of the head, looks promising!
Will be running stock bottom end.
I want to use the 317s as I can get them milled for nothing, literally. My question is how much to mill these guys?
Stock for stock, they flow the same numbers as 243/799 castings, or so im told, but with bigger chambers. The 317s have 72cc chambers, where the 243/799s have 64cc chambers. Obviously I want to get them as close to 64 as possible, but thats just not happening. If I use the math that .007 milled is 1cc, then to get to 64cc id have to mill .050+, just not possible.
But if I mill to much im going to kill my valve clearance.
Trying to get this figured out asap, id like to get the heads to the shop today if I can.
Will be running stock bottom end.
I want to use the 317s as I can get them milled for nothing, literally. My question is how much to mill these guys?
Stock for stock, they flow the same numbers as 243/799 castings, or so im told, but with bigger chambers. The 317s have 72cc chambers, where the 243/799s have 64cc chambers. Obviously I want to get them as close to 64 as possible, but thats just not happening. If I use the math that .007 milled is 1cc, then to get to 64cc id have to mill .050+, just not possible.
But if I mill to much im going to kill my valve clearance.
Trying to get this figured out asap, id like to get the heads to the shop today if I can.
02-19-2011, 10:50 PM
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Just took an interesting turn, was pulling the 317s from my newly acquired motor today, and found out my lq4 is not an lq4..... Its an lq9! I was pleasantly surprised to find flat top pistons in this thing!
I was thinking about milling 0.030, but now I dont know what to do now that I cant count on dished pistons helping me in the PTV department. If I did the math right, milling the 317s to 67ccs (0.030mill) would get my 10.5 : 1 CR. What size of cam would I still be able to get in there? Roughly, just trying to get an idea. Would a TR 224 work? Any thoughts on the power output with that and mods in sig?
Thoughts?
I was thinking about milling 0.030, but now I dont know what to do now that I cant count on dished pistons helping me in the PTV department. If I did the math right, milling the 317s to 67ccs (0.030mill) would get my 10.5 : 1 CR. What size of cam would I still be able to get in there? Roughly, just trying to get an idea. Would a TR 224 work? Any thoughts on the power output with that and mods in sig?
Thoughts?
