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Brothers,

Weathers getting better and I want to start working on my E21 again after neglecting her over the winter

Managed to locate some vented Vovlo girling calipers to update my 316.

As far as I can see, other than slotting of the calipers, the whole upgrade seems pretty straightforward.

Planning to couple these with some 323 discs, but also considering the Mini discs (which would require a hole for the hold on screw and a 1.1mm ring, but would mean I don't have to slot the caliper)

Question is this - will the 323 or mini discs be a direct fit on my 82 316 struts/hubs or do I need more than just the calipers, discs, T links & brake lines?

I know there is slightly more work with the mini ones, they are cheaper - but what exactly is involved. Any advice on which I should go for or anything that I'm overlooking would be a big big help - for example what risks are there in running the mini discs given they are shallower. I saw Nas raise his concerns over running the shallower hats in regards to the stress on the bearings, does andbody have anything to add?

Planning on doing a comprehensive write up/picture diary of all of this to help others too so all input is welcome.



Thanks in advanced

2nd stage would be upgrading the servo and master cylinder - any advanced suggestions of any plug and play parts for this would also be much appreicated

I did some reading up on this some time back. Ended up by doing the E12 brake conversion instead and converting the entire car to 5 lug.

Regarding the Girling calipers of they are 4 piston they will compensate for the offset on the brake disc. Its simple hydraulics. If the outer pistons needs to push the pad 2-3 mm longer than the inner pistons because of some offset the caliper will compensate. This is the major advantage with running brake calipers with pistons on both sides inner and outer.

So IMO this is not an issue.

A bigger issue with this type of conversion is that the 323 discs are too small in diameter. You would be better off and you would get better usage of the pads effectiveness if you use bigger discs that are grinded down to fit in diameter. As i recall the Volvo discs are around 265mm diameter and the 323 ones are 255mm. This results in the Volvo brake pads to extend beyond the brake disc.

If you ask me this is not the correct way to do it. The technology behind brakes is a mathematical study in simple statics. Distance x force. In other words the further out from the center of the hub you get your pads to work, the more effective the braking becomes.

An alternative is to install the calipers as they are, and use some E34 525i brake rotors instead. The hat height is the same (roughly) 75mm on the E21 and 76mm on the E34. The E34 disc is 302mm diameter and should be lathe´d down to the Volvo 265mm diameter. Then redrill the lug pattern.

Bear in mind that the lugs do not hold the disc in place when in use, it is the surface friction between the wheel and the hub that keep the brake disc where it is. So you will not have any problems even though one of the holes will do some overlapping.

Here´s one made for a Honda Civic.. http://tazeat.com/misc/redrilled.jpg