What exactly is the difference between e24 and m3 front calipers

[Roysneon]

I bought a set of late e24 635 front calipers and carriers for my E30 M3 suspension at the suggestion of a lot of knowledgeable people online. Got everything bolted up, went to bleed the brakes and the calipers leaked like a siv.

When looking for new calipers the e24 items were more readily available, but the part number was different than e30 m3 calipers. The carrier alone is the same number, however.

Is it just a case of the piston being .3mm bigger on one or a cosmetic difference? I had e24 calipers bolted up so I know they do fit, it's just the difference in p/n that's throwing me off.

[gath]

^^ I just skimmed through this thread but there could be some good info here..

http://www.s14.net/forums/showthread.php?36887-Has-anyone-actually-tried-E24-E28-E34-calipers

[jlevie]

Why not rebuild those calipers? The kits are inexpensive and it isn't a difficult process.

[Roysneon]

I did rebuild them. It was my first time doing so and it didn't work out. I'm in a bit of a bind and don't want to run teh risk of messing it up again. Not really sure what exactly I did wrong but the results of Superblue all over the floor/wheels/new control arms speaks for itself.

[Todd Black 88]

Didn't know about the e24 calipers, but the e28 535 front calipers work, but have a slightly larger piston.
E24 and e28 are probably the same caliper

[Roysneon]

Yes, exactly the same caliper e24=e28 535 caliper. p/n's cross reference each other. So if I used e30 M3 seal kits it would explain why they leaked if the e24 piston is bigger then, huh?

[Roysneon]

Oh God herpaderpaderp I am retarded. I assumed that the e30m3 and E24 pistons were the same size and the seals would be the same. Did not do my homework on that one. Proper seals are en route. Feeling super stupid right now.