The two bleeders Options

[emerygt350]

I just popped on my newly remastered rear brake calipers from PMB and was wondering if there was a point to the lower bleeder? I only ever bothered with the top bleeder before but now that it's bone dry I was wondering if that might be why the second bleeder exists? I will be bleeding the brakes tomorrow morning.

[Van914]

Ferrari 308 uses the same rear calipers. I think the double bleed screw is to accommodate use on it.

[Superhawk996]

Ferrari 308 uses the same rear calipers. I think the double bleed screw is to accommodate use on it.

So I’ve never actually looked at the Ferrari application. It seems they do use the caliper with the handbrake lever on the top instead of on the bottom like the 914. So that would need the bleed screw flipped 180.

The rear casting also appears to be the same at a glance but I certainly don’t have parts in hand.

I believe the Ferrari really used the /6 GT vented rear caliper. But again I have always been under the impression that the 914/6 back casting was common between the 914/4 and the 914/6 and that both the Ferrari 308 & 914/6 GT just added a spacer between the inner and outer casting to accommodate the wider vented rotor. Yes, the /6 has a larger 38 mm piston and a the stock rotor OD is a couple mm larger and a mm or so thicker. This would be an easily accommodated within a common casting.

To me that seems like more rationale why ATE might have done generic machining like bleed screws early on before the inner casting final use was known and more of the application specific machine work was done.

Would be interesting to have both applications in hand. I think PMB might have insight but suspect this topic has been beat to death in the past though the Google magic isn’t finding a thread with a 100% definitive answer on the dual bleed screws origin. Here’s a video from rebuild of Ian’s 308 calipers by PMB.


https://www.youtube.com/watch?v=oUvYRPe2bDw