What calipers to use?
 

I have just finished my 5 lug conversion on my 914, and I have 3.5 in bolt spacing for the calipers. the front suspension is from a 74 911, and it has 911 M calipers on it. The problem is that I dont have pistons in the calipers, therefore they are paperweights. Instead of just buying some used calipers for about $100 what calipers would bolt right on as a replacement? I have new rotors so I dont want to buy another set of new ones. Is there any calipers that would bolt on as an upgrade? If not does anyone have any M calipers they want to get rid of cheap? (condition doesnt matter, I just need the pistons..) Thanks all!!

SmileWavy

Lots of info here

But as long as you have the 3.5" ears then the A, the S, or the wide A will bolt on(there is no M that has 3.5" mounts)

The first 2 calipers use '70s 911 282.5x20mm rotors and the last uses the '84-89 282.5x24mm Carrera rotor

Be sure to updateto the non boosted 19.05mm m/c your car came stonk w/ a ~17mm