Differences between '89 & other SHO brakes?

[DemonNeno]

So i bought my SHO pads last night for the first time since i've owned it and turns out to have pads from a '90 SHO? Why would this be? Are all replacement calipers based on '90+ SHO parts? It's a 4/89 built SHO, but both front calipers have the enlargened piston that accepts the larger clip on the pad, whereas the '89 SHO pads had a clip about 1/2 the size... Just curious. Rotors measured up 10.2, though... I was hopin' the eyeball was playin' tricks on me and reality would've proved 10.9" rotors.. mm.. 94-95 brake upgrades...

 

[nc89sho]

90 and 89 front brakes are pretty much identicle. the rear rotors are diff between the two years and of course 90's are ABS and 89s aren't.. never heard of there being diff. sized pistons in the front calipers.

 

[DemonNeno]

That's what I figured... but I was wrong! Check for yourself! go to a local parts store, ask to compare the front pads for a '89 and '90 SHO. It seems as if the '89 had either an oddly shaped center section on the piston (like it was a small bore from the center of the piston) or the piston was indeed increased in diameter.

 

[nc89sho]

or the parts house has the wrong part listed. very common. i wish i still had my 90 parts car.. if i did, i would go check

 

[pjtoledo]

So i bought my SHO pads last night for the first time since i've owned it and turns out to have pads from a '90 SHO? Why would this be? Are all replacement calipers based on '90+ SHO parts? It's a 4/89 built SHO, but both front calipers have the enlargened piston that accepts the larger clip on the pad, whereas the '89 SHO pads had a clip about 1/2 the size... Just curious. Rotors measured up 10.2, though... I was hopin' the eyeball was playin' tricks on me and reality would've proved 10.9" rotors.. mm.. 94-95 brake upgrades...

Take a better look at the pistons. The ones with the smaller holes are SLO,,not SHO. The caliper casting is the same for both, SHOs have a thin walled steel piston with a bigger inner hole. Slos have a thick walled plastic/phenolic piston with a smaller hole. The outer diameter is the same on both. Other than composition, the difference on the pads is the clip size to hold them in the correct hole

Perry.