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Discussion Starter #1 (Edited)
Updated 06/15/12
Hey guys the bracket was a success. I didn’t want to blow my own whistle by creating something and not fully testing it, but after 3000+ miles of use/abuse I have all the data and confirmation that I needed.
here's what 3000+ miles of abuse/usage looks like on the brackets.....






Virtually no change, no heat spots no indication of any type of warping. But a visual inspection wasn't just enough for me, so I proceeded to check other actual aspect. Flatness was retained at .001" (one thousandths of an inch) across the whole length of the bracket, on all mounting surfaces, perpendicularity measured within the same region, meaning there was virtually no warp present, shape was retained; nothing changed over the course of the mileage. Hope this helps ail alot of aluminum skeptics' suspicions. This finalizes my testing phase, production would be the next phase. If anyone is interested in a set of these please let me know.
What would be needed to run these brackets on stock 18’s with cts-v/sts-v 4 pistons caliper front brembos:

-The brackets themselves (which, if anyone is interested I can get to them for 200$ for the set with mounting hardware).
-C6 Corvette Z51 front rotors 13.4” (340mm), advanced auto parts #YH200436 or gm #89060328
- Stock mounting bolts to mount bracket to spindle (will need bushings on 04 gtos mcmaster p/n 6679K16 – 2 per bracket – 4 per set)
- m12 X 1.75 bolts in 65mm length and 10.9 grade with washers.
- 5mm wheel spacers (5x120 bolt pattern), akata spacer ( http://stores.ebay.com/akataspacers ) makes good ones.
- 2004 Gto would have to use a sleeve adapter spacer bushing ( www.mcmaster.com #6679K16 )as the 05-06 gto spindle (which this bracket was modeled around) uses 14mm bolts and 2004 models use 12mm bolts.
Its all basically bolt on aside from needing to use grinding bits to grind away the inside of the rotor (about .100”) until it fits on the gto hub since corvette rotors have a slightly smaller center bore. Here is an example of a grinding bit kit one would use on something like this, if they already don't have one already http://www.sears.com/gl-46-piece-professional-rotary-tool-kit-die/p-SPM5721744803P?prdNo=20&blockNo=20&blockType=G20
Also, for 05-06 guys, I wouldn’t recommend installing brembos (regardless of which bracket used) without 04 gto lines; they are longer hence providing more slack which is much appreciated over the short stock 05-06 lines. Trying to fit stock 17’s may be successful with these brackets if you are willing to grind away at the caliper, I wouldn’t suggest it and wouldn’t guarantee function/success.


Gm Part #'s for Front Cts-V 4 Piston brembo calipers (gmpartsdirect.com is a reputable site) :
25750250 right with pads
25750249 left with pads
89047727 right with out pads
89047726 left with out pads

Thanks for looking.



Hey guys, recently I've been working on a bracket adapter to fit a front cts-v(v1)/sts-v brembo caliper onto a gto. My intention was to make something lightweight & durable as well requiring little to no augmentation to fit; form and function. A big factor/required of mine was to utilize the rotor thickness that the brembos originally bite on, which is 32mm (1.26"). A third goal was to make the stock 17's fit.
I can successfully say that I've achieved at least 2 of those goals. Alas,my goal of having the factory 17" fit wasn't one of them; I didn't account for the massive taper towards the inner end of the wheel. I compensated leeway for a 16.5" diameter but not for a 16", which is what it seems to taper down to, there is about 1/2-3/4" of space above the wheel mounting surface before the brembo would start to rub the rim, I'd estimate a 1/16" of an inch closer to the center and it would have fit all the way though; grinding a caliper (for me) is not an option. Although I did manage to bypass the taper and fit them with some wheel spacers. All in all, this was the biggest letdown for me, but besides that, the bracket fits like a glove. I utilized a 340mm (13.4") disc 32mm thick from corvette grand sport/z51 which has a very similar P.C.D. as the gto, so they fit quite nicely, problem is the inner rotor diameter where the factory hub ring centers the rotor is roughly .030" (1/32") smaller in diameter on the corvette rotor, hence the rotor would have to be cut to make fit (on the pics you see I actually cut the hub for show in order as to not cut the rotor).

Another goal achieved was a sturdy/lightweight/durable bracket, made from aluminum ofcourse.

One observation I've made is that 04 gto hubs utilize a m12x1.75 thread to mount the factory bracket while the larger 05-06 c6 derived brakes utilize a m14x2.0 thread for the factory bracket; as my test hub was a 05-06 unit and my buddy's gto is an 04, I found this out at the last minute when the mounting holes were already made to accommodate the larger thread.

Cliffs:
1. Guy wants to make brembos fit gto
2. Guy makes bolt on bracket but stock 17's don't fit
3. .......
4....... might consider stock 17" bracket in the works.

LMK what you guys think.

Damian.






 

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dum dum dum dum dudum
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Nice work. That bracket looks like a really nice piece. However with the current Brembo bracket thats out there, there is already an issue with spoke clearance if any type of dish is going to be run. With your bracket the caliper gets pushed out even further and making wheel fitment an issue, unless you run 19's that are flat or concave.
 

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Discussion Starter #3
I do not know which other bracket you speak of but I'm almost sure if there wasn't such a taper present in the wheel as it gets closer to the inner mout surface these would fit without and issue on 17's, 18's I havent' yet to test but figure it shouldn't be an issue but am not sound on that.

This was made/designed in lieu to fit the factory rotor thickness spec, so should be pretty close to the cts-v offsets as well. The factory 17 seems to have about enough space when measured to fit this offset, both from top of the rotor to mounting surface and from inner depth of wheel to the same mounting surface; I'm just unable to confirm that since the brembos get bound up right before you're able to mate the two surfaces.

I wanted to create a true bolt on, but I cannot see that happening for the 17's unless wheel spacers or miniscule grinding of the top of the caliper is done.
 

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You seriously don't know that there is already adapters for cts-v, camaro ss calipers for the front and adapters for (I think) c5 Z06 rear calipers?
 

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riding the wave!
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what did you use to grind the oem hubring that centers the rotors?
it looks clean.
 

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Discussion Starter #6
You seriously don't know that there is already adapters for cts-v, camaro ss calipers for the front and adapters for (I think) c5 Z06 rear calipers?
I seriously now am I guess heh, I was aware of attempts but nothing concrete. I just noticed that there is a bracket where you hack away at the hub casting, looks like a well made piece but not my cup of tea. Thanks for the input.

what did you use to grind the oem hubring that centers the rotors?
it looks clean.
cnc milling, this was only a test to clean up the expendable hub so I wouldn't damage a in-expendable rotor at the time.
 

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I've never seen an aluminum bracket for a brake caliper. Is that an accepted practice?
 

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Don't drink the Kool-Aid...
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I've never seen an aluminum bracket for a brake caliper. Is that an accepted practice?
95% of BBKs have aluminum mounting brackets...

You're probably thinking about the big cast iron abutment brackets used in sliding caliper assemblies.
 

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Discussion Starter #9

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Grumpy Bastage
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I just noticed that there is a bracket where you hack away at the hub casting, looks like a well made piece but not my cup of tea. Thanks for the input.
You don't need to do anything to the hub aside from cleaning casting slag off if, and only if, it gets in the way of the bracket.

Good job though, can you confirm the STS-V caliper is an identical size to the V caliper?
 

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Discussion Starter #12

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Discussion Starter #13 (Edited)
Hey guys,I got a chance to fit some oem 18" and Sacchi S32 18" wheels,

this is with a simulated 10mm spacer on oem 18", which was overkill since a 1/4"(6mm) will fit fine




Same spacer used on the Sacchi S32 18" wheel, once again overkill since a 1/4"(6mm) spacer will fit fine





Im really glad/relieved of this fitment, a 1/4" spacer is small and insignificant enough to be used with stock lug bolts. Seems like the only real modification to parts done here is the need for the center hub ring Ø on the corvette rotor must be opened up .100" in order to compensate for the gtos' larger hub ring, all which can be done with brake cylinder hone or small grinding wheel within 5 mins time.
 

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Grumpy Bastage
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No spacers wouldn't be a problem at all using a rotor like the 745's offset. The problem is the overall radius from the hub center to the caliper's highest point.
 

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I just need to get in there and get some measurements. I want to look at one of the Z's and see if their akebonos could fit. Calibrated eyeball tells me theyd be a good fit for the rear at least.
 

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Discussion Starter #18 (Edited)
When creating this kit, I had to consider the most bolt-on possible rotor and design the bracket around that rotor. The c6 rotor was a perfect match with the proper rotor thickness and close in height to the V one. I've seen the specs on the bmw 745 rotor and they did not match my criteria because they are 30mm thick to begin with (28.4mm service limit), which is the minimal thickness for oem brembos to grab on with (32mm nominal thickness and 30mm service limit), meaning that you already are running out of rotor for the brembo to grasp (per oem specs) when utilizing a 745 rotor. I needed to make something that is as close to bolt on as possible. Keeping that in mind (and the lack of available bolt-on rotors) along with the bolt-hole spacing & diameters and offsets, this was the best way for me to proceed. All cars equipped with brembos come with massive offset wheels just to clear them and are designed with them in mind, I would like to say you wouldn't need to use a spacer, but in fact you do, the oem wheel rubbed the hardline on the caliper. Therefore, minimal spacing is needed.

For 17's, I'm currently devising something to be used with the base 12.8" c6 rotor.
 

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Rotor thickness is tied to the rotor, not the caliper. Rotors rely on mass to disipate heat, they get too thin, there is a greater risk of cracking. The caliper really doesnt care. You can put brand new pads on a rotor thats is at min thickness, because min thickness is not the discard spec. It will run fine. Running the 745 rotor on a CTS caliper will cause no travel problems.

One cant even say with confidence that the heat dissipation of the thinner rotor is worse based on thickness alone. Vane design and Alloy of the rotor are bigger factors. This again goes back to the rants against Chi-Com/eBay cheap rotors, same deal. More to a rotor than being round and metal.
 

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Discussion Starter #20
Rotor thickness is tied to the rotor, not the caliper. Rotors rely on mass to disipate heat, they get too thin, there is a greater risk of cracking. The caliper really doesnt care. You can put brand new pads on a rotor thats is at min thickness, because min thickness is not the discard spec. It will run fine. Running the 745 rotor on a CTS caliper will cause no travel problems.

One cant even say with confidence that the heat dissipation of the thinner rotor is worse based on thickness alone. Vane design and Alloy of the rotor are bigger factors. This again goes back to the rants against Chi-Com/eBay cheap rotors, same deal. More to a rotor than being round and metal.
This may/may not be true. But, I didn't want to omit the oem rotor thickness, none of this was guessed, but reverse engineered. Basing that all cars equipped with these brembos (evo/sti/s60r/350z-g35/v's) come with a 32mm thick disc, I was merely replicating oem spec.
 
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