Classic/Antique Car Repair: Brake calipers, splitting halves., disc brake caliper, caliper pistons

Question
1977 MGB in the last stages of restoration.... I hope!

I purchased this car as a non-op and have spent the better part of the last two years getting it restored.  I needed to split the disc brake caliper halves in order to replace the pistons & seals... Jiffy gave up trying to get them out w/o splitting.

Now I keep reading where spliting them is a grave safety concern and it's got me worried.

I replaced all the seals including the one between the halves and used new pistons.  The cylinder walls were smooth and I cleaned all the fluid passages in the halves.  I used new bolts to put them together and torqued to the specification.

I fully understand the safety aspects of brakes, but with each caliper and the rears being on seperate lines I don't see the potential disaster.  I'd think rebuilding the master cylinder... which I also did.... would be a greater concern.

Am I missing something?  I know it's not much of a question but there has to be a reason why spliiting then rebuilding the calipers seems to be a big concern.

Any experience and thoughts would be appreciated.... I'd rather not go driving this car concerned that the brakes wouldn't work.

Thanks for your time.

Answer
Brian:

Right!  Brakes are a "big" concern. I don't think splitting the calipers and rebuilding them is as grave as it is made out to be though.  The main things are to absoultely make sure:

1.) the mating surface of the halves is absolutely perfectly clean and smooth.
2.) a new (proper sized and material "o" ring is used between the halves.
3.) the PROPER SIZE and GRADE (grade 8) NEW bolts are used and that they are tourqued to specifications.

If you have done these things (plus used new parts and seals for the caliper pistons, new bleader, etc) you shouldn't have any worries or problems, I would think.   Mostly the warnings are meant for people who would reuse the bolts, etc. and try to do the job on their dirt garage floor. Also, unless everything is spotlessly clean between the halves, it is likely you'd end up with leaks as well.   Good luck with the rest of your rebuild.  Test the brakes after you get the car on the road, locally about the neighborhood- including some hard (emergency type) stops and look for leaks or signs of other problems---if you've done everything properly - you shouldn't have any.

Brian