Is the brake plate pattern same on the 9 bolt as the 10/12 bolt, I want to get the aerospace components kit for the 10/12 bolt but will it bolt up ?

 

no, and to add to the confusion there are 2 gm 10 bolts. thirdgens use a 7.5" ring gear in the 10 bolt rears. there is a chance you could buy what you need and transfer the bolt holes to the rear you have and drill new holes and tap as needed, but not sure it'd work, or that you'd have metal where you need it.

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ICON Motorsports

1st & 3rd

 

Has to be redrilled man. I did it for the baer rear kit I have. I bought it used from someone and just used my old 9 bolt plate as an adapter and viola. Lots of material on either side of the holes so you dont have to worry about strength issues.

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If the women don't find you handsome they should at least find you handy
88 GTA Notchback with 91 gfx and ROH Snypers
Aftermarket T-56 (pain in the A$S but worth it)
Lots of things to do still

 

The bracket I purchased is supposed to be for 9 bolt, however I don't see any difference in the pictures.

 

Wow, back from the dead. Check posts 20 and 21 for pics of the 9- and 10-bolt backing plates. You'll see that the bolt pattern is different.

https://www.thirdgen.org/forums/faq-...iscs-89-a.html

JamesC

 

Question is, does anyone have measurements of the 9bolt backing plate?

 

I asked this some time ago, no responses. I ahev some plates that I will measure if I don't buy some from Ed Miller soon (if he replies)

 

I am in a similar boat. I am planning to measure my plates (still on the car) once the car goes away for the winter. Be sure to post up if you get them measured.

 

I have a set off the car, complete axle disassembled. I want to convert to at least 12" rear brakes using corvette rotors. Would prefer a 13" rear PBR setup but don't know what rotors to use, they should be 13x.81 but what car came with the same ones as used in the baer 13" rear track kit... anyone know that?

 

no one knows this????

 

I think Baer has them made. I dont know of any other car that has a 13" rotor that thin. I got mine from Baer, aluminum hat rotors and brackets.
these are the early 9bolt brackets


converting from stock size rear rotor to baer 13" alum hat rotor with 9" rear.

If you look at the 9bolt bracket on the bottom left you can see the extra holes I drilled in it.
The new Baer parts are right above it.

 

I don't think Baer made their own rotors, they drilled production rotors. The fronts on a track kit are 13"Corvette J55 (grand sport/zr1) rotors. I have a feeling the 13" rears are a production rotor too. The alu hat eradispeed are theirs obviosuly but II have seen these kits advertised as 13" rears w/ 1pc rotors.

I assume you have that all installed on your car now? Sure would be sweet if someone had the bracket dimensions and the rotor offsets.

Do you have a rotor part number???

 

They do make or have their own rotors made. If you put real GM rotors next to a Baer they are very different, look, feel, smell and taste lol.
They are based on production rotor offsets. I did the conversion 5 yrs ago? Id have to look thru my thick file to see if I have the pt# info.
If the 13inch rotor is on a production rotor it may be on a car from down under?? I know of no cars in the states with them..

 

I have a set of bare 13" track ronts and stock track fronts looked the same to me apart from the drilled holes LOL, will have to check again

part number would be super helpful

 

Yeah I have a set of 13" all steel Baer fronts also someplace. Mine are diff than "stock" I also have some 13" stilln rotors and they are the same but diff also.
Im looking for a pt#. no promises tho..
well i found PT#s, Im sure they changed them since 05 because I cant find em. prolly have to call..
301012 F, Eradispeed-plus, 88-96 C4 HD
302041 R, Eradispeed-plus, 88-96, C4,1 (these are 13"x .081)
710102 Brkt, 9" torino big brg all rotors
700162 Brkt, track for 13" rotor
800217 .500 shim package (not sure on the 8 it may be a 3)

 

I know Ed Miller offers a PBR kit with 13x0.81 rotors. He typically uses normal production rotors. I tried searching based on size, but did not find anything that matched. Maybe he will spill the beans. That is exactly the size I want to run as well, but with Wilwood FSL calipers. The search continues.

 

I know but he's not replying. I have been searching also, didn't find anything.

 

I just re-read Ed's description. He does use the Baer 13x0.81" rotors.

 

One of the 91-2 firehawk racecars has the 1LE front 2piston PBRcalipers on the rear with 13" C4 HD rotors. it used a normal 10bolt bracket with a adapter welded on.. thats what Id like to do even tho its a lil more weight.

 

The problem is, you won't have a parking brake then and they are required here. You could mount some spot calipers, in fact I have a set of wilwood spot calipers...hmmm........

 

Yes no parking brake with that setup but brembo wilwood and others have a stand alone caliper 4 e-brake..

 

That's what I meant those are called spot calipers. The brembo piece is identical to the wildwood one.

 

That is my plan as well, run rear Wilwood FSL's with their separate e-brake. I bought a set of 2010 rear brembo brakcets for the 9 bolt. I will use them as a pattern for my Wilwood brackets. I'll post up the dimensions when I get the brackets.

 

Well here are the measurements I pulled of the 2010 Camaro Brembo bracket for 9 bolt. I will be using this to build my Wilwood bracket. Measurements should be good to within 0.01" or so, assuming the bracket is dead on.

right click - view image for larger picture