so i bought a 2004 LS6 cam from a member here for my LS1.

GM says LS1 cam is 19.7mm base circle (im guessing that's diameter?) and the LS6 cam is 19mm base circle, so that's a 0.35mm diff in radius right?
0.35mm = 0.0138", stock push-rod is 7.4" so i should get one that's 7.4138 right?

I know they don't make a 7.4138 one i just wanna make sure my thinking is correct, so then i should get whatever closest which would be the 7.425" rods ??

so i should order yellow LS6 springs and 7.425 rods ?

 

From what I have measured, stock length is 7.385" gauge length. On the LS6, the difference in base circle is made up by slightly taller valves. I think the 7.400" pushrods would be a better length although a better approach would be to measure. As for the valve springs, the PAC 1215 which has a slightly higher seat value. The yellow springs have broke on quite a few guys and the PAC springs are excellent.

 

I've heard before that the stock ones are closer to 7.385, but site i checked stated stock length to be 7.4.
Maybe 7.4 would be a better choice then.

as for the springs i thought the yellow ls6 would be great since there made specifically for that cam, also i want stock reliability and fuel economy which is why i went with the LS6 cam.

The problem with yellow springs breaking, have this happened on stock engines (LS6 cam) or is it only on cammed vettes with big cams?

 

No, yellows have failed on stock engines. That is why I would recommend the PAC. The 1215 isn't as stiff as the 1218 but it is a little stiffer then the yellow spring so you won't be adding a lot of spring stiffness for no reason. The PAC's have a very long life as well.