[Dmcbrass]

I set out to replace a sticking braker caliper on my GT Saturday, with one of 4 spares that came with my car. Much to my surprise they aren't an exact match. The spares that I have are physically larger. (longer and thicker) They'll bolt up to the spindle but take larger pads and the brake line connection is in a different location. I'm suspicious that these may be the infamous 1975 Manta calipers. How can I identify what I have?

 

[BQS4]

Can you supply a picture?

 

[Sven]

same problem here... i have these small calipers that didn't work too well, and replaced them with larger ones... i am not sure if they are 75' calipers or rekord ones, or maybe they are the same.. it says rekord on the pad's box.

Are theese the same as yours?

btw. the gravel protector had to be cut up a little for the larger ones to fit.

 

[Dmcbrass]

No, those look different than mine. I'll try to get pictures posted tonight.

 

[Dmcbrass]

Ok, here's the photo. The caliper and pad on the right is the one that I removed from my GT. The one on the left was part of some spare parts I acquired with a parts car. Any opinions on what this is?

 

[BQS4]

The one on the left is the 75 brake caliper

 

[kwilford]

Ok, here's the photo. The caliper and pad on the right is the one that I removed from my GT. The one on the left was part of some spare parts I acquired with a parts car. Any opinions on what this is?

Looks a bit like the '75 Manta Big Brake (9.685 inch/246 mm diameter and 0.500"/12.7 mm thick rotor versus 9.370 inch/238 mm and 0.430"/10.9 mm thick rotor in the earlier and GT's) or maybe '77 to '81 BMW caliper. They will work on a GT, but ONLY with the bigger rotor, and require bigger wheels (at least the '75 13x5 1/2 J) for clearance to the caliper. The OEM Opel '75 calipers (48 mm) are the first photo, while the BMW solid rotor caliper (45 mm) is the second. HTH

 

[Sven]

that BMW caliper looks like the thing i have. but i am using the same rotor and 13" wheel with it with no modifficatons.. (some 13" wheels wouldn't fit, but mine do) That would also explain why i bourght the pads for it in a bmw parts store. thats handy to know. thanks!

 

[Dmcbrass]

I temporarily installed one of them on the drivers side with my stock 70 wheels. No rubbing. Has anyone else had similar success using stock GT wheels with 1975 calipers?

 

[bq97]

I installed the larger 75 calibers with stock 73 wheels. There was no interference but it was real close so I switched to modified 75 wheels.

hth
Brian

 

[Dmcbrass]

So how much clearance do you need? Is there any concern that the hub/wheel will flex on curves and cause the wheel to rub the caliper? I would rather stay with the stock wheels to retain the 1970 look.