will a 13" ZR1 rotor fit under a 1991 camaro stock 16" rim?

im assuming yes, and i'll just have to worry about my willwood caliper, but im not positive.

anyone done this yet?

 

i bet not, that is very close, but maybe on the stock camaro rims.

 

these are the stock camaro rims. 16" 91 camaro rims. the non Z06 ones in my sigpic.

 

I think ebmiller fit LS1 brakes under a stock 16" wheel which are basically the same as C5 brakes which have 13" wheels. So it should work.

 

The LS1 brakes are 12" The C5 are 12.75". The C5s wont fit but the Wilwoods have a window at the top so they have better clearance then the factory floating calipers.

 

I don't think they will, even if you use the LS1 caliper. I did fit the LS1s inside stock 16" wheels, but it was tight. I just don't think there's enough room in there.

Ed

 

Oh, well, my bad.

 

The Baer track kit uses the 13" ZR1 rotors and C4 calipers - they clear (barely) under 1991-92 Z/RS 16" wheels. I have them on my Camaro - no problems.

 

Paul, do you have any pics of your setup on hand? I'm curious to see how they got that big of a rotor to fit in there. I know they use a 5/16" thick bracket but I'd like to see a few pics of it. Also if you know, how thick is the rotor? I'll give their website another look. I know they use the C4 HD/Grand Sport calipers but it's the rest I'm not sure of.

Thanks...Ed

PS: Just checked the website. Track system uses 13"x 1.1" rotors..

 

I'm gonna change my opinion here...I think the ZR1 "HD" brakes will fit.


Ed

 

ZR1 HD brake rotors and calipers clear my 16" IROC front wheels.

 

have any pics of the setup?

 

Yes, pics please. I didn't think you could fit the front rotors in there. Did you do it yourself or is it a kit?

Ed

 

Did it myself.

I do have pics, but they are at home. I will post tonight.

The caliper just clears the inside of the rim. Mind you they are not the Grand Sport Calipers.

 

I also want to add that you can only use the front IROC wheel. The rear wheel with the 1" offset will hit the carrier and the dust cap of the hub will stick out farther than the "IROC" insert will allow.

 

OK, then here's my question: How can you run a HD rotor and not use the HD caliper? What caliper are you using, cause you can't use a 1.1" thick rotor and a standard C4 caliper that uses a .81" thick rotor. Please clear this up for me 'cause I don't get it.


Ed

 

Guys-

Sorry I took so long to get back with you. Had other obligations with the weekend....you all know how that can go.

Anyway- here is a photo of the rotor and caliper assembles prior to wheel install.

 

Here is a photo of the whole mess inside the wheel.

 

Another piece of info I want to add is that a 15" and 16" doughnut spare will not clear this setup.

The only thing that works is a 17" doughnut spare from a Corvette and it does not fit in the spare tire carrier hole in the back, so stret drivers beware.

 

Ed-

To answer your question, there are two calipers that externally are the same dimensions. The difference between them is the length of the pistons inside the caliper. The pistons used inside the caliper for the 0.81" rotor are longer than the pistons used for the 1.1" rotor.

Of course, you also need a different caliper carrier as the one for the 0.81" rotor will not work for the 1.1" rotor.

Hope this helps.

 

Wow...OK, now I believe it CAN be done, but what does your bracket look like? I'm very familiar with the differences in the calipers (I have one set of HDs and 2 sets of standard C4 brakes out in the shop), but the pistons are the same. After rebuilding 8 or so sets, the only difference I find in the calipers is the size of the opening where the rotor goes. I'll get pics. Are those just HD rotor replacement rotors from AutoZone or what? I need more info on this. Do you have a pic of your bracket, and how thick is it? And just to make sure...that's a 13" rotor, right?

Ed

 

Yes, it is a 13" rotor and it is 1.1" wide. The rotor is slotted, so no, it is not an Autozone special, but it is for a Corvette Heavy Duty Application.

The bracket looks just like the one you use in your kit, except it is 1/4" thick. I needed to fabricate a spacer to sandwich between the hub and the rotor- I will have to check the thickness.

Use the heavy duty rotor, caliper and carrier, bolt it up and go. Had it together for about 2 months and no problems at all.

 

ah HA!

so you DID have to move the rotor out and away from the spindle.


do you think a regular 1/4" slip on wheel spacer will work, or is somthing else needed?

 

That's what I thought too, even with the 1/4" bracket, I knew you had to do something else to move the rotor out, good job though. I have always believed in the 1/4" thick bracket but I know a LOT of guys who think it's too thin. I think it's fine.

Here's the pics I took today of my standard and HD calipers side by side. They are overall the same size, but you'll see the differences in the castings and width of where the rotor slides in. First one: I measured the piston area, from the back side of the caliper where the brake line attaches to the top of the pistons. Both measured right at 2.5". The one on the left is the HD caliper, the red one is the standard. On the tape, the HD measures 0 to 2.5", the standard measures 6.5"to 9"

 

Next, here's the rotor and pad opening width, measured from the piston to the inside part of the caliper. The HD caliper measures right at 2.5".

 

Now the standard, measures exactly 2".

 

Next is the casting differences, the HD has more meat in these areas:

 

And again here on the outer edges, note how thick the HD caliper is compared to the standard:

 

Another shot. Note the MUCH thicker casting in the outer edge of the HD (left) caliper:

 

Now for my bad comments:

Here's the problem I have with running a spacer behind the rotor. The rotor has has a certain sized hole in it, in case of the C4 rotors it's 71mm. The center of the hub is also a certain size in diameter. These two parts HAVE to match, otherwise the rotor will not fit correctly and won't be axially centered if it's not PERFECTLY in the center of the hub. Using a spacer there, I don't see how that can be accomplished. Even with a 1/8" thick spacer behind the rotor, it will raise the rotor just enough to cause these two parts to not be aligned correctly. There's a flat "lip" machined or cast into the stock F-body rotor, pull a wheel off and you'll see it. This is the part that keeps the rotor and wheel centered.

On the plus side of this, the C4 rotors have a good, "toight" (Goldmember) bolt pattern and it looks like this won't be a problem. I should be getting my rotor from Baer this week so we'll see what I can come up with.

Ed

 

Interesting info on the calipers. Looking in the GM parts manuals they show different pistons for each caliper, but hey, live and learn. All my calipers have been the heavy-duty type ( I have several more sets), so I have never had a standard set to look at. I do have a set of standard caliper carriers though.

The thickness of the spacer is .100", so the rotor still rests on the shoulder of the hub and everything is concentric. The absence of any and all vibration up to 105 mph confirms this . I know 1/4" A36 steel is adequate for the application. Another alternative I need to run an analysis on is using 3/16" A572 steel, if the loading does not infringe upon the factor of safety, that may negate the need for a spacer all together.

 

Oh hell, .100" isn't that much at all, and I see where it would work. Thanks to you for the info, and I'll look into the piston thing again.

Ed

 

Hey Bridgeman, you're right about the pistons: The HD pistons are dished on the back side, the standard caliper pistons aren't, hence the different part number.

Update: I finally got the rotor from Baer today, got it measured and installed on the spindle and hub. Go figure, it's the same dimentions and size as a C4 HD rotor, 13"x 1.1", just a LOT more expensive, but it is great quality, one of the best rotors I've seen up close. Guys, this thing is HUGE. So anyway, I test fitted it up on a spindle I have in the shop, with a modded C4 bracket and it fit up great. Please note: I used a 1/4" thick bracket and had to use washers between the hub and the rotor to move it out 1/8" to get the bracket in there, much like Bridgeman did. I like using a 1/4" bracket 'cause it's plentiful and cheap, and the 1/8" spacer still allows the rotor to center on the hub. This is my new baby:

 

Another:

 

Side view. I'll fit up the caliper tomorrow and post more pics:

 

More pics. Brake pad fitment, perfect with the C4 bracket:

 

Now with the HD caliper in place, again, fit is perfect. Guys, this option is VERY lucrative...true 13" rotors that fit in a 16" wheel, and I thought it couldn't be done. Many, MANY thanks to Bridgeman for getting this thing rolling again.

Let me know if anyone has any questions on the setup, I'll be playing with this kit all weekend, and it's probably gonna replace the C4 Standard brakes on my RS instead of the LS1s.


Ed

 

muahahahaha!

it works!


my vauge idea that i havent yet got to try works!

 

Corvette HD brakes sounds sweet if they really do fit under 16 inch rims. They will also work with the bracket i designed too so you won't have to make a bracket.

I thought the corvette 13 inch brake caliper looked like the picture below. At least all HD brakes for a 88-96 vette I have seen on ebay look like this.... http://cgi.ebay.com/ebaymotors/ws/eB...tem=2463395164

EDIT: Another note, corvette calipers have the almost the same if not the exact hydraulics as the 1LE caliper so a 1LE proportion valve would be a perfect match.

 

Hi Luke. I think you're right there also, but I think those are ONLY the Grand Sport calipers and maybe the Collector's Editions. From talking to the guys over on Corvette Forum and buying their C4 brakes, they have told me that ALL C4s got the bigger 13" brakes in '95 or '96, I haven't narrowed that down yet. Those calipers will work with these rotors, too, they'll just have Corvette on them.

This is a quote from my CF "caliper search" thread:

" '94 was the last year for 12" brakes since the HD brakes became standard in '95. Just so you know.", and "Sounds like the parts store is incorrect. All 95-96 cars got the HD brakes. ", Jason L.

Here's the thread:

http://forums.corvetteforum.com/zerothread?id=728447

All I know is that these big boys WILL fit, just gotta use a 1/4" thick bracket, no biggie.


Ed

 

So there are really 3 different calipers that came on the 88+ C4’s. The C4 caliper I posted above has more material on it then the standard C4 HD brakes so it is more beefy. I did notice something about the caliper I posted; it looks stickling similar to the Baer Track caliper. I wonder if the C4 grand touring caliper really is the same as the bear caliper just with corvette cast into it instead of Baer.

Below is a picture of the Baer caliper on my brothers old car.

 

Also about the 1/4 caliper bracket, I don’t see any problem with putting a spacer between the hub and the rotor to allow the use of a 5/16 caliper bracket (same thickness as Baer bracket)

 

You're right. PBR makes the calipers for Baer, along with Alcon, etc. PBR just casts BAER in the calipers, and changes the cast over for "CORVETTE" and the like. Have you looked at Baer's Grand Touring brake kits? Take a look at the calipers on them...look just like C5 calipers don't they? That's because they are, just with a little extra aluminum cast onto them.

http://www.baer.com/Products/BrakeSy...ntSystems.aspx

Think about it...Baer's Serious Street kit uses a 11" x .81" rotor....which is exactly the SAME thickness as the C4 standard rotor, and uses the front calipers for that system. Their Track kit uses 13" x 1.1" rotors, like we're talking about, and therefore uses the SAME C4 HD calipers, just cast a bit different. That difference in casting, IMHO, is just to hide the similarities between the C4 calipers so people think they can ONLY use Baer parts on their brakes. Like I mentioned, the rotor in my pictures is from Baer, and cost me $166 shipped to me- ONE rotor. Now go and price a C4 HD rotor from different brands and see the difference in price. I bought it just to make sure they were the same rotors, and they are.


This is why when you buy Baer you're just buying a name and some bling-bling. I want performance that won't break my bank account, and it can be done.


Ed

 

About your bracket comment, I had to make a 1/8" thick spacer just to get the carrier in there even with a 1/4" thick bracket, so my math tells me that you'd need a 3/16" spacer to get the 5/16" bracket to work right, and 5/16" steel is hard to find and isn't cheap. I priced a 12' section that is 5" wide (bracket material) and they quoted me $85/per 3 foot section, so the whole thing will run me $340 for all of it, just for the metal.


Ed

 

Another thing you could do is use a 1LE rotor. I think they are offset about .323". You could probably get away with a .500" bracket. We made some hubs out of the 1LE rotors for a guy the other day. I think my guy said they were .323" offset, but can't remember the exact figure. I got them from RockAuto.com and was surprised that they weren't priced too bad. I haven't been following the board like I used to. I have been over at Corvetteforum.com. I bought a wrecked 02 convertible, so I've been searching for parts.
Todd

 

If you could get your hands on some old warn out 1LE rotors they would make perfect hubs for the C4 HD setup. The 1LE rotors as hubs have a much larger offset then stock rotors as hubs. Another benefit is the 1LE rotors use bigger bearings so they can take more abuse.

Measurements:
Stock rotors machined into hub, back to face: 1.79 inches
Bear hub, back to face: 1.91 inches
Caprice 12inch rotors, back to face: 2.11 inches
1LE rotors, back to face: 2.11 inches (I believe)

Though caprice rotors are plentiful and could be used to make a hub they are the wrong bolt pattern for thirdgens.

 

toddlsf, you beat me to it

 

I try.

 

Gotta love Rock Auto... I've been looking for a bad 1LE rotor, just haven't found one. It may be worth it just to buy one and "tear it up". When I return the Baer rotor to them, I'll buy one with the refund. I have to admit, the customer service rep I spoke to at Baer was very courteous and would allow me to return the rotor if it was unused, making the testing part a no brainer.

Luke, thanks for the measurements. Since Baer makes their own hubs that's where the difference is and that's why they can fit the 5/16" bracket in there


PS: I've been thinking of jumping ship to a C4/C5 myself. Larry Burd almost has me talked into it.

Ed

 

As mentioned, the stock 15" and 16" donut spares won't fit any of these brakes...what's the options? I'm swapping to the Sport and Track Baer kit...13" up front, 12" out back, and should I just say goodbye to the spare?