List below are a couple random systems that compare the approximate weights of a Brembo Performance GT system vs. the O.E. (Original Equipment) components from various makes and models.

In many cases a Brembo Performance system has a weight savings over OE brake systems even though the Brembo Performance system utilizes multi-piston calipers and often times larger diameter discs.

A Brembo Performance GT/GT-R big brake system is commonly comprised of:

Caliper

Either a 2-piece aluminum alloy, monoblock aluminum alloy, or
billet monobloc aluminum alloy caliper

Brake Pads

typically 2 to 4 pads per caliper

Rotor/Disc

1-piece rotor
– or –
2-piece disc with billet aluminum center and outer iron disc

Brake lines

typically 2-lines per axle set

Mounting brackets

typically 2 billet brackets

1st Comparison

This is a weight comparison of the factory‪ ‎Porsche‬  911/996TT‬ (above image)

 1-piece rotor (330mm)

VS.

‪‎Brembo‬ Performance GT 355mm
2-piece disc which is roughly 6% larger.
The GT 6-piston caliper is approximately 7.5lbs.

2nd Comparison (just OE weights)

The weights of a used O.E. BMW M3 (E90/92) brake system
Caliper (F)
O.E: 7.6/11.8 lbs w/bracket, Brembo: 7.75 lbs w/o bracket
(R) 9.2 lbs
Pads: 2.0/1.6 lbs
Front: 1-piece disc: 22.6 lbs
Rear: 1-piece disc: 20.2 lbs

3rd Comparison

A used Honda Civic Si (EK) steel sliding caliper, pads, line, and 10.2″/260mm rotor
weighs approx: 21.7 lbs

VS.

Compare that to the total weight of this Lamborghini rear system which is:
approx. 24.17 lbs total.
broken down by component:
it’s 15.94 lbs for the 14″ disc and
roughly 8.24 lbs for the forged monobloc racing caliper (w/pads).

Lamborghini rear brake system (above)

4th Comparison

Sharkwerks Comparing Brembo Performance vs. an OE 2013 991 Porsche Carrera S brake system

CALIPERS:
FRONT: Brembo Performance, 6-piston monobloc, 12.10 lbs vs. the Porsche OE 6-piston caliper, 11.44 lbs
REAR: Brembo Performance, 4-piston monobloc, 9.44 lbs vs. Porsche OE 4-piston caliper, 8.08 lbs

DISC/ROTOR:
FRONT: Brembo Performance,2-piece 380mm (15″) disc,  vs. the Porsche 1-piece rotor ( ) 23.8 lbs
REAR: Brembo Performance, 2-piece 380mm (15″) disc, 17.1 lbs vs. the Porsche 1-piece rotor ( ) 19.7 lbs

Full article here on Sharkwerks.com

Than there’s carbon ceramic, for the ultimate in weight savings

Mike either has a strong finger or this Brembo CCM-R (carbon ceramic for street/track/racing) disc is nearly half the weight of iron.