C5 REAR Rotor Dimensions

[Mean 69]

the C5 and LS1 calipers are the same so that means same mounting. LS1 bracket should work with C6 Zo6 too.

Can you clarify that, please? I have a set of LS1 abutments and rotors that I bought, thinking that I could trust part number information from a website that no longer seems to be posting this information, that was listed under a "Rear C5 Brake Upgrade." Never cross-referenced the part numbers, and now that we have parts in hand, it is obvious that the true C5 stuff is not the same as the LS1 in several regards.

The Ls1 rotors have about .5" more negative offset (i.e. inboard) than a trusted but older measurement of a C5 rotor. Additionally, the LS1 abutment "must" be different in terms of offset dimensions, from the C5 abutment. Ls1= GM# 12456459, C5= GM# 12455800.

What we are specifically looking for at this point is the mount-to-centerline of the C5 abutment bracket, GM# 12455800. In other words, if you looked at the caliper bracket (abutment) viewed from above, what distance from the inboard mounting surface to the centerline of the bracket (which is also the centerline of the rotor when installed)?



Lastly, I have read that the C5 and LS1 calipers are the same, can someone substantiate this as fact, i.e. are the part numbers the same for the calipers, if not, what specifically is different about them? Mounting pins, etc the same?

Thanks guys, we could really use the facts right now.
Mark