Hi, Im new to the forum. Quick story about me: my neighbor asked me to fix up her 1975 914 that's been sitting ion her garage for 20 years after seeing the work Ive done on a couple old Fords I have. I love working on cars and foreign cars/Porsches offer a new experience for me so I agreed. Anyway, to get to my question, the pistons in the front calipers were rusted and seized and needed to be replaced. From what I have read, they are the "M' type with the anti-knock back pin in them. I can not find replacement pistons that fit the pin and am wondering if its okay to just brake/cut the pin off and use the more modern pistons that are bored out on the side that faces the pad.

I don't know that there's an off the shelf part that you suggest. Only part I'm aware of is gasket kits.

Serviceable, used, late 4 cyl front calipers shouldn't be too hard to find for a decent price, if you want to DIY.

Best way to go is send what you've got to PMB (as long as they are serviceable cores) and get restored calipers that look and work like brand new, or better.

@MikeWood99

`' date='Jul 15 2020, 04:06 PM' post='2834129']
Hi, Im new to the forum. Quick story about me: my neighbor asked me to fix up her 1975 914 that's been sitting ion her garage for 20 years after seeing the work Ive done on a couple old Fords I have. I love working on cars and foreign cars/Porsches offer a new experience for me so I agreed. Anyway, to get to my question, the pistons in the front calipers were rusted and seized and needed to be replaced. From what I have read, they are the "M' type with the anti-knock back pin in them. I can not find replacement pistons that fit the pin and am wondering if its okay to just brake/cut the pin off and use the more modern pistons that are bored out on the side that faces the pad.
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They would not be M calipers unless they were swapped from original. I have good front cores and could send them direct to PMB for rebuild. Or send to you if you want to rebuild them.