Large rotor caliper brackets

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Hugh
Satellite Sebring (RH)
Posts: 54
Joined: Tue Dec 22, 2009 9:37 am
My Cars: 1973 Plymouth Satellite Sebring 318/904/8.25
Location: Hastings, Florida

Large rotor caliper brackets

Post by Hugh » Sat Jan 18, 2014 2:49 pm

Just bought a set of large rotor pin type caliper brackets off eBay. I measure 3.25 inches center of pin hole to center of mount hole. An article at moparaction.com says 3.125 for small rotors and 3.5 c/c for large rotors. My car is in winter storage so no too easy to get to. What gives? Typo on measurements? I am not measuring either measurement listed. Anyone have experience with this?

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road chicken
GTX (RS)
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Location: SE WI

Re: Large rotor caliper brackets

Post by road chicken » Sun Jan 19, 2014 12:50 pm

Was that this article ?, ( Disc-o-tech) http://www.moparaction.com/Tech/archive/disc-main.html

I hope he got it right because I'm doing the same thing with sliders on the 11.75 disk.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

72bluNblu
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Joined: Mon Jul 15, 2013 7:28 pm
My Cars: 1971 383 SSP

Re: Large rotor caliper brackets

Post by 72bluNblu » Sun Jan 19, 2014 5:57 pm

The measurements in the article are correct, I just double checked a set of my 11.75" pin type caliper brackets and came up with 3.5". The measurements for the sliders are correct as well, I confirmed the measurements for both the 10.87 and 11.75" brackets. I'd check a set of 10.87" pin type brackets, but I don't have any of those anymore. I'm pretty sure that they're the same as listed in the article, I do recall measuring a set at one point.

I would re-check your measurements and make sure you're going center to center from the mount hole to the pin hole, and not mount-to-mount or pin-to-pin. Also, a ruler works better than a tape measure for those measurements if you still have issues, tapes are notoriously inaccurate on that first inch.

The measurements and specs from the article are good, but don't listen to the bit about the later F/M/J spindles not working. This has been tested and shown to be 100% false, you can check it yourself with the geometry numbers listed in the MM article http://www.moparmusclemagazine.com/tech ... _spindles/
'71 SSP GA4
'71 DartGT EL5 (#65 in the GT registry)
'71 DartGT GK6 ( #69 in the GT registry)
'74 Duster/71 demon tribute- primary driver
'72 Challenger-secondary driver

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Hugh
Satellite Sebring (RH)
Posts: 54
Joined: Tue Dec 22, 2009 9:37 am
My Cars: 1973 Plymouth Satellite Sebring 318/904/8.25
Location: Hastings, Florida

Re: Large rotor caliper brackets

Post by Hugh » Sun Jan 19, 2014 8:28 pm

Yeah the moparaction article was the one I used. I definitely got the wrong brackets but the seller was good about it and will give me a full refund. I did double check measurements starting at the one inch Mark and the brackets were no where near 3.5 inches. Now its either junk yard crawling or pay big bucks for repops. I really need to do the brake upgrade. Right now,the rears lock almost instantly under hard brakeing. I am going to have to downsize the rear wheel cylinders as mentioned in that article as well. I am very excited about this spring as I will also be putting the interior back together completing the conversion from column to console automatic. Thanks for the input everyone!

JimT1971RR
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My Cars: 1971 Roadrunner.
Location: Long Beach, CA

Re: Large rotor caliper brackets

Post by JimT1971RR » Sun Jan 19, 2014 11:53 pm

I have a small rotor caliper and bracket from my 71 which I measured at 3.25". It appears that your bracket is from a small rotor setup.

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