Hi guys.

In my pursuit to shed weight I have been looking into some new brake calipers that are a direct replacement for the old ones. Since I have Cortina uprights I will need to go with a set of M16 units. Rally Design have a set of Wilwood twin pots which look the goods but I am worried about the difference in pedal feel as I have read that some people have had to really stand on the brakes to get them to work after they have changed to new calipers. I am happy with my brake pedal feel and the brake balance the way they are (obviously I will have to readjust the balance after the caliper change) so I don't want to replace the calipers and have it all turn to poo. Has anyone here done a direct swap over of just the calipers without changing anything else and if so did they work ok or did the master cylinder also need replacing?
The cast numbers in one of the current calipers are 64326672 & 64326046.

My current master cylinders are Girling 3/4 for the rear and 5/8 for the front.

Changed mine to rally designs m16 replacements no issues other than I think I need to replace my sierra bias valve with an adjustable one now just to put more on the front other than that all good here,

Good luck

Usually they need bleeding properly (can be tricky because of the two bleed points) and the pads need bedding in, then they will be better than OEM. Best to use mintex pads and not wilwood ones.

I have escort uprights and replaced my M16's with wilwoods. I didn't change my master cylinder bore size and the pedal feel is fine.
I had Mintex 1144 pads - great for the road but over-heated on track.
Get good fluid (RBF600) if you're going to do track days.