G8 fronts on a First Gen

[40STY]

I know most people use the 4 pot calipers off of a CTS-V or Camaro, but I have the entire G8 wreck for my conversion, so have used the stock G8 calipers and rotors. Because I already had the parts, the whole upgrade has cost me about $90US, for machining of the hubs and the piece of alloy for the brackets. I don't know about in the USA, but here in Oz, G8 (Commodore) calipers and rotors can be found cheap, so even if you had to buy the calipers and rotors, it would still be less than $250US for the front setup.

The car already had a single piston disc setup from a 70's Australian Holden HQ (which were similar to the first gen single piston calipers), attached to drum spindles.

• The discs were cut off and the remaining hub turned down to accept the G8 disc (outside of hub and centre hole).
• I used a 20mm thick piece of 6061 alloy for the brackets with a template I found online for adapting LS1 calipers onto a first gen, as the mounting points are the same for the G8 calipers. I think I had to use the thicker piece for the bracket because I machined down an existing disc, rather than use a drum hub (which brings the mounting face closer to the spindle). If a drum hub was used, the bracket would be much thinner and would have to be steel, not alloy. There is probably LS1 caliper brackets available that would be the right thickness.
• 3/8 was cut off the top mounting point of the drum spindle, to get all 3 mounting points in the same plane.
• Even though the G8 uses a slightly different PCD, it has thicker M14 wheel studs, so the holes in the rotor are larger and slide onto the 5x4.75 PCD of the original hub.
• Longer bolts were needed for the top mounting point and to go through the bracket and steering arm.

[Mr Nick]

Nice work! I just picked up an 09 G8 GT as my daily driver a few weeks ago, it's a great car, I've wanted one for a while.

[srh3trinity]

I love my g8 gt as a daily driver. I am planning on going with the cts-v brakes though because I keep having issues with warped rotors on the stock brakes.