HSV OEM Rear Brake System Upgrades
The high-end Monaro GTOs from Holden’s performance division, HSV, come with 315mm diameter (12.4-inch) vented rear rotors compared to the 286mm (11.2-inch) rear rotor for our US GTOs. Many may have seen this upgrade from JHP which comes with calipers, stainless steel brake lines, and rotors. The calipers in this upgrade, and the ones used by HSV, are the same rear calipers used on our Pontiac GTOs. The bracket is different to allow the caliper to be positioned further from the center to mate with the larger diameter rotor. You can also buy the 315mm rear rotors from DBA - Disk Brakes Australia (www.dba.com.au
) via a US distributor like www.Man-a-Fre.com
(part # DBA049). Man-a-Fre also carries the bracket to use your OEM caliper to mate with it (part # BKT049). Prices for this combination are $110 to $170 for each DBA rotor, depending on the grade and surface configuration, and about $180 for the brackets.
The HSV rotors are a bolt-on install. The only issue that has to be considered for this set-up to work are the brake lines - they now have to reach 0.6 inch further out. You have three options; purchase longer rear brake lines from an Australian supplier, special order stainless steel lines from StopTech.com, or continue using stock brake lines. There is already slack in the stock brake lines to account for caliper removal when changing brake pads. If you unclip the brake line from its mounting bracket on the dust shield, you will have enough play to get the caliper over the rotor and onto the bracket. You may have to bend the metal tube slightly toward the mounting plate to reinstall the clip.
I choose not to go with the 315mm rear rotor as my first upgrade step. I wasn’t sure I needed the increase performance. Other GTO owners have reported adequate performance with the OEM rear brakes and, even though Corvettes are lighter vehicles, the C5 Z06s have 11.5 inch rear rotors so I felt the OEM 2005 vented rotors should be suitable. I concluded if I found out later that I needed the larger diameter rear rotors, I could add them the next time I needed new rear rotors.
05 Brakes w/ C5Pads, K&N CAI, TBCoolantByPass, -CAGS, , +Outlets, DeadPedal, UnSpoiled, GasCapHook, PedalsRightSideUp, HitchToGo,
Last edited by Xman; 05-02-2013 at 10:43 AM.