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Ishmael
04-24-2010, 07:17 PM
It takes me forever to get anything done on my car. One reason is that when I actually do find time to work on it in nice weather I can't just take steps forward. I know its the case with everyone but just once I want something to bolt on without a problem. My front rotors aren't centered in my calipers. They are too far inboard. Should I take some material off the abutment mounting pads? Or does it matter if they aren't centered? I'm just at the test fit stage.
Thanks

MrQuick
04-24-2010, 08:20 PM
need more info:
brake kit?
hub used?
abutment used?
adapter bracket?

Ishmael
04-25-2010, 05:09 AM
Its a c5 caliper over c4 rotor on the stock firebird hubs using touring classics bracket.

Ron.in.SoCal
04-25-2010, 08:57 AM
The rotor needs to be centered in the middle of the caliper. Using a measuring device gets it perfect. So either there's a problem with the abutment bracket or you need to shim it. Pics would help...

Keep at it Bro!

Apogee
04-27-2010, 07:54 AM
Scott, how "not centered" is it?

It's possible that you just have funky spindles or that the shoulder on the spindle where the inner wheel bearing(s) seat is worn, locating the hub and rotor further inboard than "stock". Is this ocurring on one side or both?

In any event, you want the rotor centered as close as possible with the TC Hybrid kit since the C4 HD rotor is already 4mm narrower at 28mm than what the C5/C6 calipers were designed for, 32mm. FWIW, PBR suggests centered +/-.5mm [.02"] for the OEM's which is a bit arbitrary IMO since double that works just fine in most applications. With the TC Hybrid kit though, I would do whatever was needed to hit the PBR tolerance.

Tobin
KORE3

Ishmael
04-27-2010, 04:33 PM
Its about 1/4 on the inboard side and 3/8 on the other. if someone would tell me how to post a photo I would put some in.

LSx_88_Ciera
04-27-2010, 04:41 PM
Click go advanced below the quick post window in the advanced window scroll down and click manage attachments.

Ishmael
04-27-2010, 04:46 PM
Thanks. I don't know if the photos worked but The inboard pad won't push back any further and the rotor is about 1/8 off the pad or 1/4 off the caliper. Its about 3/8ths of the other side. The photos are a bit decieving.

shep
04-27-2010, 07:34 PM
Don't some of the pontiac hubs set further back toward the spindle than the chevy's making a narrower track width? It looks like the abutment sholders could be milled off to gain the clearence you need not sure what that might do to the strength of the abutment though. Did you use any spacers between the spindle and the mounting bracket? There were also a couple of different spindles through the years some with a taller boss on the spindle than others

Ishmael
04-28-2010, 06:10 PM
No spacers between the spindle and bracket. Perhaps the mounting surfaces on the spindle could be milled down. Could anyone with a camaro measure theirs for me? I thought about the abutment bracket as that would seem easier but I also wondered about the strength. Can anyone chime in on this?

bijanmaleki
04-28-2010, 07:25 PM
Like said above, space the caliper out, of you have to get longer hardware and some good washers.

Apogee
04-29-2010, 06:33 AM
Scott, I'd be very hesitant to start cutting down the spindle...not so much the upper mounting boss, but rather the lower steering arm mount. As for the abutment, we've had customers machine down the mounting pads up to 1/8" before for a variety of reasons without any issues, but the more threads you have there, the better.

I'd be more interested in figuring out why your installation appears to be different than the "typical" TC Hybrid kit installation. Running it as it looks now seems to be asking to eject that outer pad once it wears a little bit. Hopefully some others with the TC kit will chime in. Do you have any pictures of the installation process...spindle, bracket, hub, rotor, pab, etc? Maybe someone will see something that doesn't look right.

Tobin
KORE3

Chad-1stGen
04-29-2010, 08:17 AM
There are two different types of Camaro spindles depending if the car care from the factory with disc or drum brakes. The difference is in the depth of the mounting points which appears to be your problem.

See discussion here:
http://www.pozziracing.com/brakes.htm#disc_brake_spindle

He has a crappy small pic of the spindles side by side but look at the mounting points.

It could be that you bought a drum spindle kit and are trying to use it on a disc spindle?

Apogee
04-29-2010, 11:51 AM
There are two different types of Camaro spindles depending if the car care from the factory with disc or drum brakes. The difference is in the depth of the mounting points which appears to be your problem...

...It could be that you bought a drum spindle kit and are trying to use it on a disc spindle?

The difference between the disc and drum bosses is almost 5/8" with the disc boss being the shorter of the two, significantly more than what's shown in the pictures above IMHO. The steering arm mounting points are the same regardless of the A/F/X forged spindle being used.

Tobin
KORE3

Ishmael
04-29-2010, 04:30 PM
Its a pontiac version of the f body spindle. the only difference that I knew of was that it used a smaller bolt in the boss. The boss sticks out 11/16ths. The hub is 3 1/2 deep.

Ishmael
04-29-2010, 04:36 PM
Can't get the rest of the pics up. I've exceeded my quota.
The spindle looks normal - not a disc spindle.
The rotor is 5mm from the left and 11mm from the right.
I wonder if the hub is too short. Tobin, you told a guy at chevelles.com that the disc hub is 9/16ths shorter than the drum hub which is 6mm. If I had a disc hub on a drum spindle would it have caused this problem? I can't see it because if that were the case and I went with a theoretical drum hub it would put me 3 more mm than where I want to be.
The easiest solution here seems to be a 3mm spacer behind the rotor. Anyone know where I can get one - Tobin do you have them? Or should I be milling down the abuttment?

gort69
05-03-2010, 06:05 PM
If you're using the Pontiac drum hub, that's probably your problem. They're different than the Camaro drum hub, and will locate the rotor diffently compared to the Camaro hub. If you have 1st gen Camaro drum hubs then nevermind.

I use the C5/C4 hybrid set-up, but with Speed Tech brackets and '68 Camaro drum hubs, and everything lines up perfectly.

Ishmael
05-04-2010, 06:23 PM
How are the camaro and firebird drum hubs different? If the bird hubs are shorter can I get away with spacers?

JRouche
05-04-2010, 10:30 PM
How are the camaro and firebird drum hubs different? If the bird hubs are shorter can I get away with spacers?


YES.. Shims or washers is the way to center the caliper. Dont remove material from the spindle or caliper mounts. You dont have a too tight fitment but more of a too loose fitment. Which is good.

I would use proper shims, not hardware washers. There is a diff. I would use machinery shims before washers. They have a smaller ID that will just clear the OD of the bolt and make for a fuller load surface. VS a washer that might have a smaller load surface.

But more importantly is the parallel surface of hardware type washers. They are NOT parallel. They are far from it, they are usually stamped and have a lip.. Get a ground washer, or shim to center the caliper.

Oh, and dont forget about the bolt. It may be too short after shimming. Make sure to replace the bolt with a quality piece if you have to. JR

FYI... You can get the rotor to spin centered within a blond hair with the proper shims. IMO.. Dont rely on the "centering" of the calipers pads to get you close. Get it spinning parallel and tight, and once you do you wont look back. JR

cheapthrillz
05-05-2010, 05:08 AM
Try a cheap feeler gauge between the PAB and rotor. That's what I did and it works pretty well.

Apogee
05-05-2010, 06:06 AM
How are the camaro and firebird drum hubs different? If the bird hubs are shorter can I get away with spacers?

I'm pretty sure that the Pontiac hubs are wider than the Camaro hubs...hence the "WideTrack" marketing campaign. They certainly look that way in the pictures you posted. For reference, the Chevy drum hub measures ~2.415" from the face of the flange to the back lip where the oil seal installs measuring parallel to the axis of the hub.

I'm not a fan of spacers between the hub and rotor due to runnout issues that typically go with them, so KORE3 does not offer anything like that at this time.

Tobin
KORE3

Ishmael
05-05-2010, 12:53 PM
So if Pontiac hubs are wider and I have determined my spindles are normal than why are my rotors running inboard? Additionally what's the difference between a shim and a spacer? Does anyone make spacers that will fit inside the hub?

JRouche
05-05-2010, 10:17 PM
Additionally what's the difference between a shim and a spacer? Does anyone make spacers that will fit inside the hub?

Just to clarify. I didnt mean to shim the rotor or hub. I meant shimming the caliper to spindle. Thats a common practice.

Shims or spacers?? Its all the same. Basically its a thin piece of metal that is either ground for parallelism or a thin sheet of metal (can be soft metal or spring hard) that is measured for a correct thickness. Its a uniformed piece of metal that can be anywhere from .001" thickness up to what ever the supplier provides. If you need a thicker shim then a machined (ground) spacer covers that area. JR

Ishmael
05-06-2010, 11:27 AM
What I need is a wheel spacer that will fit inside under the rotor hat. I know it isn't the best action but I can't figure out why the rotor won't line up since the spindle is the same as a camaro spindle at the boss and the hub is the same as a camaro hub according to what came from touring-classics. Is it possble that the spindle had been machined bringing the flange ( or whatever its called) where the hub is supposed to stop, back a little ways or that the bearings have been pressed in too far on both hubs? Does somebody have some spindles that could measure that distance for me? Or does someone know where I can find a spacer that is 5.9 inches in diameter and 3mm thick? Short of having some made, I can't find them anywhere.

a67
05-06-2010, 01:18 PM
See the eBay link in this thread:

https://www.pro-touring.com/forum/showthread.php?t=68230

Appears that kit comes with shims for between the hub & rotor. Maybe contact the ebay seller for the thickness and if they may be purchased separately.

Bob.

Ishmael
05-06-2010, 02:36 PM
thanks for the link,
Tobin I hope you are reading this cause I got some new numbers.
First, I've got spindles that look like camaro spindles but have the smaller boss bolts.
2. I can't get the seal on the back of the hub to within a 1/4" inch of the back of the spindle so maybe I have the wrong bearings in the wrong hubs - see number 3
3. Pontiac hubs are 2 5/8" and the Chevy hubs are 2 3/8" if you measure them like touring classics from the bottom of the hub to the face. My hubs are 6 cm which is 2.36 inches or 2 3/8" I imagine. If I chev hubs on a somehow pontiac spindle and the wrong bearings could it locate the hub in the wrong place? If I was able to move it over the problem would be worse.
4. The rotor is 18mm or 0.708 inches thick - not sure the conversion on that. The hat is 6mm or 0.236 inches thick. I ordered c4 rotors from my parts place. Is this the right thickness.
As the pirate with the ship's wheel sticking out of his pants said, "arrrg, this is is drivin' me nuts!"

a67
05-06-2010, 04:21 PM
It sounds like the difference between the Chevy and Pontiac hub is 1/4".

At the same time it would move the rotor out further for too much of a misalignment in the other direction.

It sounds like these are the standard duty C4 rotors (12" x .80"). Note that the rear C4 rotors have slightly less offset. Using those instead of a front rotor will move the disc portion toward the outside of the car by about 1/8".

Don't know if you currently have front or rear rotors.

Since this was a kit, have you contacted the vendor?

Bob.

Ishmael
05-06-2010, 05:24 PM
It wasn't a kit. I got the adapter from Touring classics. Then I got the rest of the parts from my local parts place. I've got front rotors. if the rears are the same size I might be able to make them work. What diameter are c4 rear rotors? Should I be worried that the hubs aren't closer to the spindle which would actually make the problem worse?

LSx_88_Ciera
05-06-2010, 05:32 PM
What diameter are c4 rear rotors? Should I be worried that the hubs aren't closer to the spindle which would actually make the problem worse?

12"
I wouldn't worry.

Ishmael
05-06-2010, 05:38 PM
Sounds like trying on the rears is a better option than using a spacer. I'd still like to figure out why it isn't working properly as is.

LSx_88_Ciera
05-06-2010, 05:50 PM
Sounds like trying on the rears is a better option than using a spacer. I'd still like to figure out why it isn't working properly as is.

Aren't the fronts 13" if so the caliper won't line up right if you use a rear, the pad will hang over the edge of the rotor.

Ishmael
05-06-2010, 06:23 PM
Aren't the fronts 13" if so the caliper won't line up right if you use a rear, the pad will hang over the edge of the rotor.

Ya, I'm getting tired and stupid.
I just reread Tobin's post about the chev drum hub. Mine are 2.36 if I measured right. 0.09" is 2.28mm which is close to the 3mm I'm out. I'll have to remeasure tomorrow but I'm pretty sure that's the right measurement. Where would those hubs have come from and why would they be on my car?

a67
05-06-2010, 07:33 PM
It wasn't a kit. I got the adapter from Touring classics. Then I got the rest of the parts from my local parts place. I've got front rotors. if the rears are the same size I might be able to make them work. What diameter are c4 rear rotors? Should I be worried that the hubs aren't closer to the spindle which would actually make the problem worse?

OK, so doesn't Touring Classics state what remaining parts are required to work with their adapters? Geez, any body can sell parts, why don't they back them up??

C4 standard brake rotors, front & rear, are 12" x .80". Only difference is the offset.

Go back to the vendor of the adapters!!!!

When they are selling something, THEY HAVE TO SUPPORT IT!

If not, then they should be gone, out of business!!!!

How are we supposed to guess what their design goals are?!?!?!

Are they a supporting vendor of Pro-Touring?

Bob.

LSx_88_Ciera
05-06-2010, 08:00 PM
C4 standard brake rotors, front & rear, are 12" x .80". Only difference is the offset.

Bob.

Depends on the year 84-94 Base 12/12, 95-96 13/12, ZR1 13/12

gort69
05-06-2010, 10:02 PM
OK, so doesn't Touring Classics state what remaining parts are required to work with their adapters? Geez, any body can sell parts, why don't they back them up??

C4 standard brake rotors, front & rear, are 12" x .80". Only difference is the offset.

Go back to the vendor of the adapters!!!!

When they are selling something, THEY HAVE TO SUPPORT IT!

If not, then they should be gone, out of business!!!!

How are we supposed to guess what their design goals are?!?!?!

Are they a supporting vendor of Pro-Touring?

Bob.

Touring Classics is out of business. They were first rate top notch nice people.

They used to show a photo on their site that demonstated the difference between some of the Pontiac hubs and the Chevy hubs. Somewhere Scott has some mismatched parts that're screwing things up.

Ishmael
05-07-2010, 04:53 AM
OK, so doesn't Touring Classics state what remaining parts are required to work with their adapters? Geez, any body can sell parts, why don't they back them up??

C4 standard brake rotors, front & rear, are 12" x .80". Only difference is the offset.

Go back to the vendor of the adapters!!!!

When they are selling something, THEY HAVE TO SUPPORT IT!

If not, then they should be gone, out of business!!!!

How are we supposed to guess what their design goals are?!?!?!

Are they a supporting vendor of Pro-Touring?

Bob.

They are out of business unfortunately. Noel was helpful but it took me a long time to get this together. Something in there is outside of our control. I have the right hubs per his instructions. Perhaps the brackets are too thick but I doubt it. My spindle is isn't the one with 5/8 bolt boss - its the 1/2" but it looks just like the other two. Perhaps that's it. I thought the fronts were 13 -they were supposed to be and I thought that's what I ordered. Are the 13's a different thickness than the 12's?

gort69
05-07-2010, 06:29 AM
The C4 13" rotors are 1.10" thick.

LSx_88_Ciera
05-07-2010, 08:36 AM
What happened to the pics you had posted?

Ishmael
05-07-2010, 08:40 AM
I took them down because I wanted to put up more and had exceeded my limit. By the time I was ready to post up the new ones, someone had answered the question that was related to the new ones so it no longer made sense to post. What pic do you need? I'll even take new pics to try to get this mystery solved.

LSx_88_Ciera
05-07-2010, 08:49 AM
One showing where the pads would contact the rotor face and how much clearance there is between the rotor diameter and the caliper.
I know this may sound stupid but I am wondering if you have an caliper bracket for a 12" rotor and a caliper for a 13" given the diff in thickness between the 12 and 13" rotors and the high amount of clearance you have.
I am reaching I know.

a67
05-07-2010, 09:31 AM
One showing where the pads would contact the rotor face and how much clearance there is between the rotor diameter and the caliper.
I know this may sound stupid but I am wondering if you have an caliper bracket for a 12" rotor and a caliper for a 13" given the diff in thickness between the 12 and 13" rotors and the high amount of clearance you have.
I am reaching I know.

He is using C5 calipers which is why the centering is so critical. They are for a 32mm thick rotor.

C4 HD are 28mm thick.,

C4 standard are 20.5mm thick. Which is what he has.

What Ishmael needs to do is to find out more about the brackets he has. IOW, what are the proper parts to go with them.

He may actually be better off starting over. Figuring out which rotor and caliper will fit inside of the wheels. Then getting a new bracket (in steel !), for that purpose.

Bob.

68firebird
05-07-2010, 11:24 AM
They are out of business unfortunately. Noel was helpful but it took me a long time to get this together. Something in there is outside of our control. I have the right hubs per his instructions. Perhaps the brackets are too thick but I doubt it. My spindle is isn't the one with 5/8 bolt boss - its the 1/2" but it looks just like the other two. Perhaps that's it. I thought the fronts were 13 -they were supposed to be and I thought that's what I ordered. Are the 13's a different thickness than the 12's?

was your bracket made to go with the 5/8 bolt boss? the kit I just bought is supposed to go with a 5/8 bolt boss and mine is 1/2 inch also. I'm expecting to do some kind of mod to get it to work, just don't know yet until I get it in. Did you have to do any modification to get it to bolt up properly? Is there anyway you can get a pic up of what the bracket looks like bolted on?

Ishmael
05-07-2010, 12:32 PM
One showing where the pads would contact the rotor face and how much clearance there is between the rotor diameter and the caliper.
I know this may sound stupid but I am wondering if you have an caliper bracket for a 12" rotor and a caliper for a 13" given the diff in thickness between the 12 and 13" rotors and the high amount of clearance you have.
I am reaching I know.

You're not reaching. I just got home, and after placing the mother's day tree in the yard where my wife will see it, I measured the rotor - 12 inches. The kit calls for a 13 rotor. I told the guys at the store to send me rotors for a 95, and I said C4. I should have been very clear. I don't remember Noel offering a kit for a 12' and 13" - only 13". There barely looks to be room for a 13" rotor to spin in therebut I didn't think there was a lot of area of pad/rotor overlap.

Well, some days and three pages later we figure it out and I probably wouldn't have done so without you guys. My wife and neighbour have been asking me how I was ever going to figure this out. It was even suggested that I send it to a mechanic. I told them you guys would help. (crying a little). Thanks guys.

Ishmael
05-07-2010, 12:35 PM
was your bracket made to go with the 5/8 bolt boss? the kit I just bought is supposed to go with a 5/8 bolt boss and mine is 1/2 inch also. I'm expecting to do some kind of mod to get it to work, just don't know yet until I get it in. Did you have to do any modification to get it to bolt up properly? Is there anyway you can get a pic up of what the bracket looks like bolted on?

Noel was very helpful here. He sent me 1/2 bolts and adapters that fit right in. I'll take pics of both and post them up. I just have to cancel my spacers order and order some new rotors first. That's done. Here are the photos. If you've got your spindles off, I would have them drilled and tapped. You'll have a stronger bolt. The 1/2 bolt is hard to find. And I had to grind a few threads off the one bolt to get it to fit. Noel would have had to make that spacer up as well.

gort69
05-07-2010, 01:17 PM
Glad you got it figured out.

Don't forget that the 13" C4 rotors are directional. Order a R and an L.

Good luck!

68firebird
05-07-2010, 02:02 PM
Noel was very helpful here. He sent me 1/2 bolts and adapters that fit right in. I'll take pics of both and post them up. I just have to cancel my spacers order and order some new rotors first. That's done. Here are the photos. If you've got your spindles off, I would have them drilled and tapped. You'll have a stronger bolt. The 1/2 bolt is hard to find. And I had to grind a few threads off the one bolt to get it to fit. Noel would have had to make that spacer up as well.

Very helpful, thank you Scott. It's a good idea to have it drilled and tapped, I might just have the machine shop do it when I drop the hubs off to get turned.