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Done! CTS-V V1 w/dished wheels + E-brake (Write up + Pics)

4K views 13 replies 7 participants last post by  SVTKILLA 
#1 · (Edited)
Alright. It's done!

While other setups have been described ad nauseum, it's really a small subset of us with nary a solution for running Brembos w/18" dished wheels. I have just buttoned the car back-up, and would like to share some of the solutions I came up with as well as the hurdles you need to overcome. Also, looking for some input from the experts as to any grave concerns you have with this setup before I crash into a tree.

I'll add part numbers eventually, but right now I just want to enjoy a beer and get as much of this info up before I forget everything.

This is basically the setup used by XBoT. Reference his build here: http://www.ls1gto.com/forums/showthread.php?t=524578

So, a recap of the parts used:

Rotors:

(2) 2002-2006 (or so) 745i FRONT brake rotors
(2) 2002-2006 (or so) 745i FRONT brake rotors with the inside of the rotor hats machined to the diameter of the E-Brake shoes. reference XBoT's thread. The rotors fit just fine over the shoes, and the ebrake can both hold and stop the car. Should be about 7.5"....measure inside of your stock rear rotor to get exact spec. In this pic, the surface with the BLUE line needs to be machined.



Tip: Use whatever rotors you'd like....but I'm of the opinion decent quality blanks are just fine. To that end, rockauto has centric ones with black coated hats so they dont rust. Recommend getting those, at negligible additional cost. I already have to sand and paint my rear hats which have some slight surface rust from just sitting on the car in Virginia humidity.

Tip: you need centering rings for these rotors to be hubcentric. Don't even bother with this setup if you can't find/machine rings. The front hubs have that bevel deal going on, so remember that.

Calipers
(2) Front CTS-v1 calipers
(2) Rear Gen 5 Camaro SS Calipers
(1) AC Delco front caliper hardware set (the clips and pins)
(1) AC Delco rear caliper hardware set

Tip: There's some interchangability with calipers here. I used rear SS calipers because they were cheaper at the time than rear CTS-V, which are the same as STS-V, which allegedly are the same as SRT-8 cars or something. The Fronts are a little trickier though, I think the Camaro Brembos have larger bolt holes, blah blah blah. Get the CTS-V fronts.

Remember, you need to machine the mounting points of the front calipers to fit with the "proxes style" brackets. Either way, machine the calipers and test fit EVERYTHING before you powdercoat.

Pads

(1) set of Front pads to fit front CTS-V gen 1 calipers. I got acdelco. whatever. will maybe upgrade later but I wanted to just make everything work first.
(1) set of rear pads to fit rear brembo calipers. I got acdelco. whatever. will maybe upgrade later but I wanted to just make everything work first

Additional stuff

(1) Pair of 3mm spacers for the front wheels. Ok. here's where it gets interesting. When the front rotors are fully seated, they sit farther inboard than the lip on the hub where the hub ring for my WHEELS sit. So....when the wheel is on, even fully seated it doesn't mate up against the rotor, allowing for play. The spacer will soak up the delta, while only adding (subtracting?..) like, 1mm of actual additional offset over a stock rotor.

(1) 04 GTO stainless lines, had to orientate the fronts right but after I figured it out it's just fine. Ref: (http://www.ls1gto.com/forums/showthread.php?t=818113)

-Slightly longer (i used 50mm, but 45mm i think would be perfect) bolts for the rear calipers. The extra meat from the bracket plus lock washers needs slightly more length to fully thread into the calipers


-M12/.5" washers of varying thicknesses for spacing the rear calipers perfectly to align to the centerline of the rotors....more on this later. I got the ones that Lowes has and that was fine.


Problems, and their solutions:


1) front rotor/ wheel spacing gap. solved with the aforementioned spacer, see pic.





2) rear dustshield. I'm not sure wtf other people did, but i took the damn bolts off from the hub and cut through then pulled the whole shield off. Left one little part for the brake hard line mounting, but otherwise said to hell with everything. I'm sure I'm going to have my work cut out for me with dust, but whatever. Not a DD, i'll survive.

3) Rear caliper to rotor spacing. As close as this was, I can't believe there's barely any mention of this in other threads. The rear calipers are just barely wider inside than the thickness of the rotor. I had to use a washer on each bolt between the kunckle and the bracket to align the caliper correctly with the centerline of the rotor. At first, I test fitted everything with the rotors not fully seated.

.....this didn't work well. The caliper was interfering with the rotor face. Like an idiot, I ended up taking the car around the block to see how bad it really was. The interference was so bad it would hold the car in place, even on a slight grade. No need to give me shit about this, I know I should have tried to fix it first. Just don't make the same mistake. Ground some material (prob a nosehair's worth of thickness) off the caliper as well as the rotor face.

See pics for how close the damn things come. I lucked out with the washers from Lowes, but i can imagine that manufacturing tolerances may make your life worse than mine when it comes to fitment here. I guess my best advice would be buy washers of varying thicknesses.



4) Grinding of front knuckle to fit caliper. Once I had the caliper machined to match the contour of the bracket, the knuckle needed more material taken off than I expected. I'm not concerned or anything, it was just more than what I thought would be necessary. I'd rather take it off the knuckle than the caliper, as it's pretty hearty.


Tip: remember to get your crossovers swapped on the fronts pre powdercoat, and on the day of install mock everything up on your living room floor before going to throw everything on the car. Did the rears and then realized my bleeders were on the bottom. "Oh that's peculiar...why are they on the bottom?" Oh, because I wasn't paying attention and had sides mixed up. :judge:


Ultimately, this was one of the more involved installs I've done in a LONG time. I'm not saying it was difficult, or even frustrating, I just feel like there was tweaking and fiddling the whole way to get everything right. Again, not hard, just "involved." Like doing a bathroom (which may be a stupid analogy because I've never redone a bathroom) ...or drawing as a little kid. It's not HARD....just...takes a while to get it all right the way you want.

I hope this is useful for the next guy. I'll try and add more info and pretty up the thread but something's better than nothing for now.

Oh btw....these brakes ROCK!!!! :woot:
 

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#3 ·
Great job on this. I'll be doing this soon also. I have the same brackets and followed xbot's thread.
 
#5 ·
I can't see the pic where the inside of rotors need to be clearanced. Maybe it's my phone, could you pm me the pic and any more you have?
 
#8 ·
How come you used front rotors for the rear? Rear 745I wouldn't have worked?
 
#9 ·
no. maybe? who knows. ref the XBoT thread, etc. the whole way this setup works is a function (among other things) of alignment between the centerline of the rotors to the centerline of the calipers when mounted on the knuckle. The brackets are a thickness that makes sure this alignment is correct.

the hat size is also important, particularly in order to use the ebrake. even then, remember....you still need to machine the inside a little to get to the right diameter. Maybe rear 7 series rotors work...if they're smaller than the fronts, I doubt it. I wouldn't even bother trying anything else other than what's been "proven" to work, albeit the machine work.

The guys with the rear vette rotors or stoptech rotors (? IIRC) in the rear with the bohnman kits push the caliper out into the spokes of wheels like the Rapps/CCWs, etc. That's the whole point of the proxes/XBoT setup.
 
#11 ·
Nice write-up
 
#12 ·
Great write up, Also where did you find the proxies front brackets? I picked a set of the Bohnman front brackets but need the proxies to be able to run the 745I rotors instead of the 2010+ camaro rotors. From what I can tell the 745I rotors have similar offset to the 2004 front rotors...
 
#13 ·
the net offset ends up being roughly similar otherwise none of this would work.

I'm not sure where one could easily acquire the brackets nowadays, and I'm worried about dropping names and stuff in this thread for fear of getting it locked for non-sponsor concerns. I'd say search for previous threads and start there, if you catch my drift.

I *think* Bohnman may have been involved and made them at one point, but I don't remember.
 
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