I finally had the time, the proper scale and all of the calipers varieties around to do a little comparison weighing. All calipers are without pins, springs and pads.

And the winners are:

Brembo Calipers = 4lbs. 6oz. (front 911 strut 3" spacing, or early 914 strut w/o caliper spacers, or late 914 strut with ClubHub 48mm pistons, #109 Pad)


S-Calipers = 5lbs. 6oz. (front 911 strut with 3.5" spacing, 48mm pistons #45 pad)


L-Caliper = 5lbs. 6oz. (rear early 65-68 911 caliper with 2.25" spacing 35mm pistons, #30 pad)


Wide L-Caliper = 5lbs. 10oz. (rear early 911S 67-68, 38mm pistons, #30 pad)


911 Rear M-Caliper = 6lbs. 2oz (rear 911 69-83, 38mm pistons, #31 pad)


914 Rear Caliper = 6lbs. 10oz. (rear 914 All, 33mm pistons, #30 pad)


914 Front Caliper = 6lbs. 14oz. (front 914 all, 42mm pistons, #31 pad)


M-Caliper = 7lbs. 6oz. (911 & 914-6 Front, can be used on early 914 w/o spacers, 48mm pistons, #31 pad)


A-Caliper = 9lbs. 2oz. (911SC all front 3.5" spacing, 48mm pistons, #45 pad)


Wide A-Caliper = 9lbs. 4oz. (911 Carrera all 3.5" spacing, 48mm pistons, #45 pad)

[same picture as above... just has 4mm wider spacers.]

Couple of things to note. The very lightest calipers and the very heaviest calipers share the same 48mm pistons and "almost" the same size pad. The 109 pad is the same pad as the BMW 320i... just as wide as the #45 pad but a couple of mm shorter.

Stands to reason a 3" 911T/914-6 strut with Brembo's is the lightest most effective system in this batch. Looking at the top and the bottom... you could shave almost 10lbs. of un-sprung/semi-sprung weight off your suspension and get the same performance!

mmmmmmmmm.... Mine are the lightest! Yaaaa!!!

Those brembos are great. Light weight and cheap! I got some from the junkyard for my 912.

Eric,

These are the combined weight of two calipers, correct?
I've got the Carrera calipers and knew they were heavy even without something to compare to.

Andys

No... that's one caliper.

I never have been a fan of those calipers on a 914 for the weight reason. They are fine calipers and pretty much a staple in the Porsche line-up since 1978 but there's a couple issues that make me not want them on my car:

1. The rotors are the 24mm vented rotor. This adds weight beyond the 20mm standard vented rotor. Rotational Mass is the last place you would want to add weight. I have "never" heard of a 914 that is braking properly that has ever experienced fade on a 20mm vented rotor. If you check the historics and the HSR 2 Litre Challenge, all of those cars are wheel to wheel racing... HARD... on 20mm rotors and 908/S-Calipers.

2. The weight of the caliper - As you can see, the S-Caliper is a full 8lbs lighter (we're talking pair now) and it has the same piston and pad area. S-Caliper pads are actually thicker for racing purposes.

That said, some say the S-Calipers flex. I have yet to experience this on any S-Calipers that I've had. I've gone through pad bedding procedures that left the brakes smoking and I was "looking" for flex at the time. I dub thee an "Internet Myth"... YMMV

This is great info. Thanks. So I have my A calipers apart and they are very clean inside. The spacers that are in the centers are about 11mm thick. Are these considered wide A or regular?

Those are Wide A-Calipers. (what's with the "Andys" and the Carrera calipers?)

That's the luck of the $40 swap meet find. A is for Andy anyway!

So Eric, what is the difference between a 914/4 and /6 rear rotor? Diameter? I know the 4s are 1mm thicker and about half the price. I just need to drill some holes for the studs to pass through. I was thinking this may be a better way to go for my application.

What do they come on ?

Diameter, not thickness. Once you machine the holes in the -4 rotors you're about even cost wise.

Dang,

I'm gonna drill mine full of lightening holes, go with hollow core pistons, and add small helium balloons.

Damn. I need some S calipers. My A's are boat anchors.

Various old italian cars. I got mine from an Alfa. They were like $40 a side. I had to go through them before I could put them on the car though.

They look like this

mine look like this PMB style

Wow those look nice!

Nice
Eric - do you stock rebuild Brembos that look that nice?
Wonder what rear caliper Brembo options are out there, maybe with an e-brake??

It was almost a shame to cover them up with wheels... Until I stood on the brakes the first time!

Anybody got weights for the Boxster calipers? I may be heading in that direction if I follow-through with my latest crazy plans.

I usually stock a pair or two of those.

Hi bud,

How you doing? Do you have a pair of these for the blue car

Bob B

12 years later ...

Just adding another data point here. Not nearly at precise as Eric’s work (I only had digital bathroom scales), I installed Boxster non-S, black front calipers at around 6.7 pounds each with the adapters. I already had 24mm rotors with Carrera calipers, so this move saved weight over my existing set up and added braking capacity. Dual pistons and maybe 25% more pad area. They also fit under 15” rims.

Click to view attachment

Click to view attachment

For the track car I'm using Wilwoods at just under 4lbs 10oz. Rotors with hats are 9lbs. My adapter plate adds maybe 8oz...

John,
@wndsrfr
What rotor/hat combo are you using with that caliper?
Thx

@Eric_Shea i am sending you a PM , so as not to clog up this thread, but main question is for '75 car currently running stock calipers with 5 lug(drilled stock 4 lug rotor to 5 lug) - if i wanted to convert to the 20mm rotors and use these 3" space lighter S- caliper, what else would be needed to complete the conversion? any spacer at the mount on the strut?
- oh and i have 16" Fuchs 6'' front and 7'' rear.
Phil

I think you would need 911 struts and hubs to make the rotor offset work for the caliper
but I'll let Eric confirm.

While I'm sure someone has tried a spacer or adaptor, there's no easy way to put a 3" 911 caliper on a 914 front strut. It also requires a 911 front hub.

Got the hats from Rebel Racing and the rotors are Wilwood 160-0471 and the calipers are 120-11131. See post #20 on this page: http://www.914world.com/bbs2/index.php?sho...&hl=wilwood

The Brembo style caliper in question will bolt directly to an “early” 914 strut. Spacers need to be removed for it to work with the solid rotors but it’s all doable. This is the basic kit we make for Willhoit Restorations for their hot 356’s.

Other musings... LeMans was won on a 20mm rotor. Our cars are 2,000lbs. And last but not least, rotating mass is the worst place to add weight

I'm moving over to a 5 lug and converting my '75 front suspension/brakes to use 20mm rotor with a brembo caliper. This is an M- caliper set-up. The easiest path for me was to pick up these early oil filled 911 Boge struts. These are already set-up with a 20mm rotor.


Click to view attachment

Click to view attachment

They are from a 1971 911 and have the 3" M Caliper spacing. I did a quick check with the 911 struts in my 914 when I got them and they really are a drop in. I also receive the calipers yesterday and took a quick picture:

Click to view attachment

The 4lb reduction is a big difference in the caliber weight. These new calipers have a 3" spacing and just bolt on. They use a larger pad from a BMW 320. This is one of the few upgrades that I've done that drops in.

I'm getting the 20mm vented sport rotors from PMB, which are $88 for a pair. That was cheaper them getting the 911 rotors resurfaced and cleaned. I've got the Boge knuckles and hubs over at PMB for restoration. There are Bilstein B6 inserts for the Boge struts that I've got on order to finish up the conversion.

Good luck.

DaveB

I don't think I saw these mentioned in this thread..

Just as a Data Point..

914-6 Rear Calipers are 7.41 lbs each

914-6 GT Rear Calipers are 7.7 lbs each