After checking numerous threads of fittng Brembo calipers on this site and our local Croatian Alfa site, we decided to make this for ourselves. First customer is a friend's 147 1.6 120 Hp, but everything is the same for all 147/156/GT
We decided to fit Brembo calipers and discs from 166.
It is easier to fit Brembo from Mito and regular 305x28 discs from GTA, but they are very hard to find and quite expensive.
Combination of 305 GTA regular calipers, discs and hubs were discarded because of expense and too much work for fiting, hard to find hubs/replacing bearing, changing original brake lines and replacing outside parts of steering rack if one wants to fit it properly.
After experimenting and measuring we found that fitting 310x28 original 166 discs was he best option (instead of 305x28 GTA) because of several reasons:
-this disc is "deeper" alowing to have more outside space for bigger calipers, and less problem with wheel ET
-having more space for caliper brackets (with 305x28 disc there is less space and caliper is harder to fit, if not impossible to fit properly)
-on 310 disc caliper can be mounted 100% properly allowing a brake pad to fit exact on disc
-on 305 disc caliper can NOT be mounted 100% properly, calipers do not have enough space and pads are too big to fit exact on disc, they go over disc
-this combination allows to use original brake lines without any modification
-if adaptors are made properly there is no need for new mounting screws, original screws from 147 plus original screws from 166 calipers are used
What have to be done:
-drilling new holes in discs for 5x98 near original holes (166 discs have 10 holes and only 5 holes have to be drilled - touching original 5)
-driling holes for disc mounting screws
-removing dics protection
-little work on removing material from Brembo calipes where caliper and hub touch each other
(here on the picture is show only position where material has to be removed, it is not that much material, because they touch on the angle, not on full width)
That's all !!!
What about wheels?
On 17" wheels with ET35, depending of wheel internal, there is possiblity to use only 3-4 mm spacer. Alfa wheels for GTA will fit with no problems.
I have tested 16" wheels with ET30,5 (GTV 3.0) and with ET30 (from 164) and they fit with no problems, without any spacer, there is more then enough space.