LS1 Bore Size????
#1
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I have been searching for the past couple of days and have got several different answers out of this. Wut is the stock bore size on the LS1. I just want to make sure wut is right. Thanks in advance.
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#9
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Okay, now I am confused. Is it 99 or 00 block that can take more? 3.898 is your bore size btw. I have heard .010 for 99 or 00 and older and .020 for either 00 or 01 and newer. Which is correct? I know that in 01 some f-bods had ls6 blocks, is this why?
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98- go .005 over
99-02- go .010 over
I wouldn't go more than that. The ls6 came in some f bodies in 01-02 from what I heard was a shortage of ls1 blocks. The ls6 block is really no better than an ls1 strength wise, but would not need modified to run ls6 valley cover like an ls1 does.
99-02- go .010 over
I wouldn't go more than that. The ls6 came in some f bodies in 01-02 from what I heard was a shortage of ls1 blocks. The ls6 block is really no better than an ls1 strength wise, but would not need modified to run ls6 valley cover like an ls1 does.
#12
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3.905 is the most common size for aftermarket pistons. You want .003" difference in the bore and piston. So a 3.898 + .010= 3.908 and 3.908 - .003" difference = 3.905. Makes perfect sense now doesn't it? Cleared myself up as well.
Am I right or not? I think it is though.
Am I right or not? I think it is though.
#13
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98 blocks
3.898
+.005
-----
3.903
So for a 98 block you would want to order 3.900" pistons
And for 99+ blocks
3.898
+.010
-----
3.908
So order a 3.905 piston
This also varies for n2o cars I know but I am not sure about FI cars. I think n2o cars need a little more room in the bore so a 3.900-3.903 piston would be correct for them depending on shot right?
3.898
+.005
-----
3.903
So for a 98 block you would want to order 3.900" pistons
And for 99+ blocks
3.898
+.010
-----
3.908
So order a 3.905 piston
This also varies for n2o cars I know but I am not sure about FI cars. I think n2o cars need a little more room in the bore so a 3.900-3.903 piston would be correct for them depending on shot right?
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some good information i just learn.i know for head gasket cometic sells 2 diffrent sizes of bores right?but is it needed to bore over the block?can it just be clean and thats it without boring it?
#15
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I believe cometic sells one for 3.9" and one for 4" bores, roughly. You would need the 3.9" for your application. Unless you had your block sleeved with Dart and then you'd need the bigger ones. Til then stick with the regular size ones.
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Originally Posted by 2000_LS1
98 blocks
3.898
+.005
-----
3.903
So for a 98 block you would want to order 3.900" pistons
And for 99+ blocks
3.898
+.010
-----
3.908
So order a 3.905 piston
This also varies for n2o cars I know but I am not sure about FI cars. I think n2o cars need a little more room in the bore so a 3.900-3.903 piston would be correct for them depending on shot right?
3.898
+.005
-----
3.903
So for a 98 block you would want to order 3.900" pistons
And for 99+ blocks
3.898
+.010
-----
3.908
So order a 3.905 piston
This also varies for n2o cars I know but I am not sure about FI cars. I think n2o cars need a little more room in the bore so a 3.900-3.903 piston would be correct for them depending on shot right?
#17
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hmmm, I didn't know the manufactures automatically did that. My machine shop told me otherwise. Hell, it made sense to me, the whole .010 bore = 3.908 then taking away the .003" from the piston = 3.905". Are you 100% sure about that?