So I have the turbo 4 piston calipers for my 86 fc and I don't have the mounting bolts. I need to find out the size and the thread pattern of the bolts. As well with the back caliper bolts, I got the car with no brakes and I'm trying to piece them together but i need help.

 

Mazda stealership could solve that problem out for you. I usually dont suggest autozone to people but they do sell caliper bolts kit. I hope that help

 

Yeah I could give that a shot I just hope they are willing to give up the bolt thread pattern and size, and auto-zone had slider bolts that go inside the caliper but not the mounting bolt like I need

 

The bolt size is an M10 1.25 pitch. Almost 27mm long with a 14mm head.

In regards to autozone not having them: get ready because no parts store will have them. It seems Mazda didn't anticipate FC3S caliper bolts going missing. Stores will have M10 1.25 pitch 30mm bolts but these will be too long and impact the rotor. Fastenal is your best bet for finding the right length.

I ended up using the e brake bolt, same pitch and length, and using the 30mm on the e brake because there was nothing for it to hit.

 

If you find a bolt that is the right thread but wrong length, use a washer or two, and that will shorten them up enough.

 

Junkyard or anyone on the forums local to you that might be parting out there car.

 

That way you know thats bolt that belongs there. Try Craigslist to or ebay

 

Possible look up the part number from the dealer then cross reference that with other vehicles then head to the junk yard. I'm sure the rx7 isn't the only vehicle that uses that caliper bolt.

 

part # FB01-26-121A ..you need 2 per side ..so 4.

 

I shorten bolts all the time with either a band saw or a hack saw. Use a bench grinder to make a nice nose on the bolt and you'll be good to go.

 

Same here,sort of.
I dremel mine actually with the small disc.Works good,and you can just "buff the edge" a bit to take the burr off.