JasonWW

iTrader: (2)

So the C6 Z06 rotor has the 16mm backspace covered.

A 40mm backspace rotor would work with every rim, but you might not need that much or else the rotor may not actually be able to move that far back. IT WON'T, 30mm IS ABOUT THE TALLEST HAT THAT WILL FIT.

So we would need one hat with a backspace in the of about 28-30mm. So this would be ideal:

16mm (Z06)
28mm (custom hat)

There are also combinations where you can add a small spacer behind the rim and longer studs. This may get you into the Z06 sized rotor or at least a shallower offset size.

JasonWW

iTrader: (2)

Check this post:
http://www.thirdgen.org/techboard/po...7-post103.html

Hmmmm, after crunching the numbers this is pretty much the size of the C6 Z06 rotor. I wonder if it is?

GR33N GoblinM6

iTrader: (14)

include the cost of new 18" wheels and now you are over the cost of the stoptech kit...

which is why i wanted to keep this to the 13" rotors so we can use 17" wheels..

JasonWW

iTrader: (2)

Yeah, I kinda hijacked this thread. Sorry about that.

I'll be running 19's anyway so no big woop for me and for those already running 18+ rims.

I haven't looked for 13" rotors, but most of the stuff is the same. The offsets are going to be similar whether it's a 13 or 14 inch rotor. The mounting brackets will probably be a similar design as well. A lot of things I'm talking about carry over.

No one found any 13" rotors either, did they? So my offset and spoke clearance measurements should still be valid regardless of the rotor diameter.

JasonWW

iTrader: (2)

For all the guys who need to have the rotor spaced back, I wonder if we can turn down a stock rotor and use it as a mount for a hat similar to this:



And then just bolt on either a 13" or 14" rotor ring.

I'll try and contact eboggs and ask him about this rotor hat setup.

EDIT. Ok, he bought this setup from Precision Brakes which has since gone belly up.

JasonWW

iTrader: (2)

The more I think about it, it seems we need to look at a vette racing forum. The C5 racers are probably going to use a 17 rim for grippy race tires which limits them to a 13 rotor, but they are probably going to convert to a 4 piston caliper. So obvioulsy they are going to need to space their rotors back some just like we are wanting to do. There must already be a rotor or rotor/hat combo out there that would work for us as well. We just need to find it.

JasonWW

iTrader: (2)

Colman has these billet aluminum hats and can be drilled for 4.75 pattern for $140 each. Cast aluminum is $80. Here are the offsets they come in.
1 7/8"
2"
2 1/8"
2 3/8"
2 1/2"
______________________________________
ANOTHER OPTION

If you look here:
http://www.colemanracing.com/catalog...15a7cea32a57bf

Coleman says they offer "heavy duty directional vane brake rotors are available in thicknesses from .900" to 1.100" and diameters of 11-3/4" to 13". These are custom rotors and are made to your specs." for $135. I don't have an account so I can't look at their catalog, but hopefully someone can.


w02ramair, where did you see those rotor rings for $100 each?

JasonWW

iTrader: (2)

OK, for you 13" guys, here's what you may need. The above hat (8-Bolt 7-5/8" B.C.) either billet, cast or steel for $90.


And this rotor for $147:


There is also a 32 vane version for $137, but I think it fits another style hat.

I think the hats have an oversized center bore, so we'll probably need some simple rings to make sure it's centered properly.

They also offer some 14" rotors for $175 and some 15" rotors for $262. That's about all I could find from Coleman.

Now we need to measure how far back the rotors can ACTUALLY go. I guess I'll volunter to pull my wheel off and measure.

JasonWW

iTrader: (2)

Well, I didn't have to pull a wheel off, but I got under there and checked. Looks like bad news for most of us. The closest obstruction is the lower A-arm. I don't think even 15" rotors would clear it. Anyway, there is about 1/2" or 12mm of room there with my 12" F-body rotors. If you already have the C5 rotors then the gap would be .7" or 18mm.



This means that for some of you, you will have to use a spacer on the front to clear your spokes. No way around it.

It also means those above hats won't work as they are too tall. We need to find one 1.2" or about 30mm or so. I found one from Coleman, but it's a lightweight part designed for solid discs and would have to be drilled for our bolt pattern. I doubt this would work for us.
http://www.colemanracing.com/catalog...15a7cea32a57bf

If we can't find a hat then we'll be forced to use the rotors we have now (LS1, C5) and then just get spacers to push our rims out to clear. Maybe we should look at the OEM rotors again looking for about a 30mm offset.

JasonWW

iTrader: (2)

Actually your old list was pretty good once I remembered you were listing the rotor height and not offset.

The Z06 rotor height is 47mm and we can go up to about a 61mm or so before hitting the A-arm.

If anyone know of some sites that carries rotor hats, see if you can find one about 30mm tall in a 5 lug pattern, we can always redrill it. We also need to find some cheaper rotor rings. $147 for 13" and $175 for 14" and $275 for 15" is pretty pricey.

JasonWW

iTrader: (2)

Something just occured to me, will the A-arm gap change as the suspension compresses? I had my car jacked up and the wheel at full extension.

JasonWW

iTrader: (2)

I talked to Luca (GrnDragon) who is running 15" rotors and he said that Coleman can custom make hats for $250 each. Luckily it is a one time purchase. Then for those wanting a 13" rotor you can pick them up for about $150 each.

So front calipers $370
If you need the spoke clearance and don't want to use wheel spacers:
$500 for hats
$300 for rotor rings

For those that can use the C5 13" or 14" rotor:
$60-80 for 13" C5 rotors
$180 14" for Z06 rotors

So we need to try the C5 rotors first and see if a spacer would work to get you the spoke clearance you need. It will save a ton of money over the 2 piece rotors. If your worried about the front wheels sticking out, consider adding some camber up front. About 1* can improve cornering grip as well as tuck the top of the tire in.

Here's my car with 1* camber and old rims. I could certainly space my front wheels out more if I needed to.



The wild card is finding another OEM rotor that would work, but I have no idea what they would cost plus the re-drilling. Might be pretty high.

GR33N GoblinM6

iTrader: (14)

see you guys...

you can buy all this crap from stoptech... already made..

the purpose of this whole thread was to do this with some stock rotors.. from another vehicle... and keep the price down... now you guys want 14 or 15... using rotors and hats... you're going to be way above what i deemed feasibly cheap...

as of right now.. i would rather use the C5 rotors, my Kore3 brakets, and run a spacer for the front ... granted the front wheels will stick out more than i would like them to.. but thats basically the route i will take with this...

JasonWW

iTrader: (2)

I don't think you see what I'm doing here. I'm figuring out about 3 different setups at once for you guys as well as myself.

I've pretty much determined that the only economical way to do it is with 1 piece rotors. Going to 2 piece really jacks up the cost.

So far I've found a way for the guys who want the 13" rotor, 14" rotor and for myself, I was looking into the 15". Now since the 13" and 14" rotors have the same offset just different diameters, most things concerning fitment and spoke clearance are the same.

If you don't care about the 15" I was working on, then just ignore it, no big deal. I've already determined it would add an extra $900 to the cost just for that 1 extra inch. For me it's not worth it. If I could get it down to $200-$300 over the cost of the 14" then I might do it. For both the looks, braking and lighter weight.

So to summarize, if you want a cheap 13"-14" kit your going to have to use the OEM rotors and check your spoke clearance. I should clear fine with no spacers using a C6 (and C6 Z06) rim, but most will probably need to use at least a small spacer and maybe longer studs up front. And there you go, a very affordable 4 piston setup.

JasonWW

iTrader: (2)

For those who can use the 14" rotor, it is almost a bolt in swap. It just needs a little finessing. Maybe a mm here or there to get it lined up with the rotor just right.

I'm wondering if the factory mount holes can be welded in and new holes drilled. This might only be needed on one of the holes. Another thought was drilling the holes out just a little and using a steel offset bushing. Once it's lined up it can be welded into place to keep it from moving. I'm not sure if the caliper needs to be moved left or right, but one way can be done with spacers. The other way may have to be done by milling the spindle bosses down just a little. I'll know more once I can do some actual test fitting.

As you can see, the spacing made into the caliper pushes it out almost exactly one inch. The spacing between the bolts is exactly the same and they both use the LS1 12mm bolt diameters. It will bolt on, but the caliper is not lined up just right.

JasonWW

iTrader: (2)

Here's some more pics for the thread.






Here they are mounted on the caddy.

JasonWW

iTrader: (2)

Something else just occured to me. For the guys who want to run the 13" rotor it may actually be hard to mount the caliper due to the mounting lugs being so long.

If you look at this pic of the stock spindle you will see that the CTS-V caliper mounting holes would be approximately 1/2" closer to the hub.



Something like this:


Even with a new bracket, can those lugs be cut off enough to allow this caliper to fit? You guys may be better off going to a radial mount caliper. It looks like this:




Perhaps the viper caliper as was mentioned on post #66 would work better.
Post 66

Or a compromise for making the CTS-V caliper s fit would be to use a conventional bracket and see if the Z51 13.4" rotors would fit under your 17" rims. Then the holes would only need to move back 1/4", which would require less cutting on the spindle.

Am I the only one still interested in this?

Hello......

Did we ever find out the GTO rotors size and offset?

JasonWW

iTrader: (2)

The 05 GTO rotor looks like it might work. The offset may be a tad too much based on the pics I've seen, but that can be fixed by using a thin spacer on the hub to move the rotor out just enough to clear the A-arm. I still haven't found all the specs on it, but it may offer the most caliper clearance for you guys who are lacking spoke clearance.

Cop Car

iTrader: (14)

so what you are saying, and what im seeing, is that you can get the CTS-V calipers to bolt up correctly?

we just need to come up with some rotor?

JasonWW

iTrader: (2)

Almost, due to the bolt size and spacing, they bolt up very closely with the 14" rotor. It's off a little, but it's close. I'm getting my info from people who have tried to make it work, but I have not tried to fit them together myself. I'm getting my new 19" rims and tires together right now so once that's done I'll buy one caliper and rotor and do some test fitting for myself. I'll then be able to tell you guys in exactly which direction and the amount they are off. Hopefully the spindle mods will be minimal.

There are a lot of factors involved, due to some people wanting 13" rotors, some who have enough spoke clearance with the C5 rotors and some who need more clearance, hence finding a 13" rotor that is more offset. I'm really having a hard time seeing this particular caliper used with a 13" rotor due to the long mounting lugs built into it. For a 13" rotor, a Evo, or Viper version of this Brembo caliper may be the better choice as the mounting lugs are shorter. I don't know what those calipers cost, but it's going to be a pretty custom setup anyway you look at it. Mounting brackets will probably have to be owner built.

If you want the guys at Kore3 to make you custom brackets, expect 8-12 weeks and about $200-$250. I'm personally going to try and make mine fit with the 14" Z06 rotor. I'll probably modify the factory spindle mounts so that the calipers just bolt on.

If your confused on your options, let me know your specifics, such as current caliper to spoke clearance, and what rotor and rim you have. Based on that I can probably tell you what your best option is.