amx 69 brake system choice?

hi,any advice would be greatly apreciated here. I'm gonna replace every bushing in my suspension and since evtg is diassembled and ready to sandblast and paint , i 'm having a look at my brake system with bendix 4 pistons calipers. I'm wondering if i must go back with that system. (The master needs a replace, the calipers need a refresh, the pads look new, the rotors have surface rust but not measured yet, all the lines need replace and i can't assume evtg that 's in that brake system as ''original''). 

The 79 Spirit brakes are arguably just as good as the old Bendix four piston, and easier to get parts for. The main differences between the two are four opposed piston caliper vs. sliding single piston, and solid vs. vented rotors. The four opposed pistons might have a bit more "grip" power than the sliding single piston, but shouldn't be that much difference. The rotors are another story! The solid rotors of the old Bendix system will heat up a lot faster than the vented rotors of the 79 system. Will it make a noticeable difference? Under regular street driving probably not. If you were road racing the car you would eventually notice more fade with the solid rotor.

Parts cost and availability are really the only serious factors, IMHO. Given that, I'd take the 79 brakes over the 69. Rotors for 79-83 AMCs are around $60 each new... for now. Some places don't have suppliers (Advance doesn't, AutoZone does... and is where the just under $60 price comes from). For that reason I'd investigate Scarebird options. They sell custom caliper brackets and use commonly available newer model rotors that fit your spindles. They have a big rotor kit available now as well. I've used their older conversion kits and they are just as good as the 79 Concord brakes, and use the same master cylinder (can use the one you have now). If the rotors you have now are good and you already have the 79 brake setup, you may as well use it. Rotors for these will only get more expensive and harder to find as demand goes down though. When it's time to replace them 5-10 years from now they may be expensive. But you can always worry about that then...  I have 79 Spirit brakes on my 63 Classic. replaced rotors 2-3 years ago, and as much as I drive it now should be good for another 20 years.

There are four piston vented rotor options -- Aerospace Components and Wilwood both make nice kits if you want to spend the money.

If you already have access to the 79 then this is by far the cheaper option and for street drive-ability also a very good option.

thanks both for reply ,read them with gerat attention

The 1979 brakes are a poor design. Had them on 2 cars over the years. First on a 1978 ford granada then on a 1981 Concord DL with a 258. The 4 cylander cars have different tiny pads and calipers. They do not interchange with the 6 cyl brakes. The 1982-83 Concord brakes are the gm low friction ones same pads and calipers as 82 and up Eagle and are completely different. My 85 Eagle had 350000km on the original calipers and they worked perfect.

I had so much trouble with those ford ones siezing up every few months. Many new calipers, pads and hoses and warped rotors almost on a yearly basis. I let them go with the 1981 Concord when it went to car heaven and went the toyota scarebird route for my Javelin.

Edited by maximus7001 - Mar/24/2018 at 8:02am