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Discussion Starter #1
Trying to attach my brake calipers to my T-bird IRS. Rotors measure 10.5. I have rebulit Cobra calipers. However caliper mounting bracket holes do not line up with the spindle holes . Do I need the North Racecars bracket? I understand the only difference between the Cobra and Mustang calipers is the bracket size. Could my local Ford dealer have given me the wrong calipers?
 

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drmcat
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The Cobra brakes need the North kit and larger rotors (11.65) to work with the tbird IRS. Keep in mind the Cobra rotors also won't bolt right up to the tbird hub. Breeze or Mike Forte can set you straight with pre-machined rotors I believe. Do a search for "IRS Cobra brakes", LOTS of info.
I'm not 100% sure but I think the only difference is the bracket (which lets you run the larger rotors) and the color. Both are single piston calipers.

BTW, Max at 5-Star had brand new cobra calipers loaded for something like $175 or so for the pair, impossible to beat.

HTH,
mcat
 

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Discussion Starter #3
Now I am really confused. Got a Cypress pallet, they provided 10.5 rotors that fit,holes have not been redrilled infact they appear to be brand new.
 

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drmcat
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The 10.5 rotors are stock tbird and have a 5x4.25 inch bolt pattern for the tbird hubs. These rotors won't work with the Cobra calipers, which were designed for 11.65 rotors. The machine work is needed on cobra rotors since they are designed for a 5x4.5 inch Mustang bolt pattern, and the center opening for the hub is a different size than the tbird as well. So you will need:
1) caliper adapter from North
2) hubs with 4x4.5 bolt pattern (Cobra hubs from Mike Forte, or have Stu Spencer redrill yours)
3) Cobra rotors - will need machining of the center hole if you have your stock tbird hubs redrilled.
It is confusing, I ended up returning cobra hubs I had already bought and just staying with the stock tbird setup since a lot of people seem happy with them.
 

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Well, you'd need tbird rotors, but you'd also need wheels to fit the tbird 5x4.25" bolt pattern. Not sure if it's an isue finding a set of wheels with fronts in 4 or 5 lug mustang pattern, and rear's in the tbird lug pattern or not. But like most things, when you deviate from bone stock donor build $'s come into play.

-Matt
 

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Discussion Starter #7
Maybe part of my confusion is I think Cypress machined down the rotors,rear bolt pattern is the same as on the front. Does this make sense?
 

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You have a similar issue to me.

Forstly cobra calipes won't work with T bird discs.

Secondly, there are two width T bird rotors, .9 inch and .7 inch. The thinner one is the 89-92 I believe and the wider ones are 93-97 The calipers need to match the rotors.

Measure them and call Breeze and get the correct rotors or calipers. Autozone also stock the calipers for about $140 with pads.
 

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drmcat
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The most straightforward thing you can do is to go with everything stock tbird and have the hubs drilled for 5x4.5 bolt pattern. You can elongate the stock rotor bolt holes with a file or grinder so that they fit (or have them machined/buy a pre-machined set from one of the suppliers that advertise on this site). Since the rotor is centered by the hub it's not a big issue, but then you can run any Mustang wheel. Note you can't run 15" rims with the cobra rotors/calipers if this is important to you.

Stock:
Stock hubs, calipers, and rotors
15" or 17" rims can be used, t-bird bolt pattern

Modified Stock??:
Stock calipers and rotors (10.5")
redrill hubs for 5x4.5 pattern
elongate wheel stud holes
15" or 17" rims can be used, Mustang bolt pattern

Cobra:
Cobra calipers and rotors(11.65")
Caliper Adapter kit from North
Cobra hubs or redrilled t-bird hubs and machined rotors
Only 17" rims can be used, Mustang bolt pattern


Definitely read the brake thread:
http://www.ffcars.com/ubb/ultimatebb.php/ubb/get_topic/f/1/t/061006.html
 

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Discussion Starter #11
Thanks everyone, took Marky advice placed an online order with Breeze for the Tbird calipers for the .7 rotors.
 
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