124 Spider Brake Upgrades

bandit · Post by **bandit** » Sat Dec 30, 2006 8:34 pm

what size rotors are those ? and off what ???
nice job btw looks like a good upgrade !!!

Daniel

lanciahf · Post by **lanciahf** » Sat Dec 30, 2006 9:01 pm

Rotors are from a 1985.5 Fiat Spider, see Whoa Brakes website for details.

http://www.whoabrakes.com/index.html

No Connection to owner other than a satisfied customer.
Ralph

fiatS2000 · Post by **fiatS2000** » Mon Jan 01, 2007 12:38 am

I can't go wrong with getting the entire front braking system for under $100; Master cyl., Metal brake lines(X10), brake hoses(X4), calipers, used pads(if this works, I will need new ones, I can get them from BPB for $45), and rotors. At first look, it seems that it can be made to work. The Maserati rotor is larger in every dimension except the center hole which appears to be the same as Fiat and does center itself on the Fiat hub. The pins that hold the rotor to the hub and help locate the wheels on the Fiat rotor are different. On the Maserati rotor, they are only a countersunk allen bolt that only holds the rotor to the hub and sits flush with the face of the rotor. They are also in a different location than the Fiat ones, if I wish to use the locating pins, I will have to drill out new holes in the Maserati rotor. Another issue is that the "hat"( I dont know thw correct term) is taller on the maserati rotor and if you just try to place the rotor on the hub, the braking surface of the rotor will hit the shield before the rotor sits flush on the hub. Luckly the "hat" is also larger in diameter and the stock fiat spacers fit inside the hat. With one spacer inside, the rotor sits flush on the hub, but also touches the rear shield. With two spacers, the braking surface of the rotor will be in about the same location as the stock rotor.
here are a few pics:
http://smg.photobucket.com/albums/v27/e ... %20brakes/
I will continue the write up at a later time.

HAPPY NEW YEAR EVERY ONE!!!

So Cal Mark · Post by **So Cal Mark** » Mon Jan 01, 2007 1:30 am

with 2 spacers under the hat, you're moving the wheel farther out also. First question is whether the lug bolts have enough threads, and second is by moving the wheels out you're increasing the load on the outer wheel bearing. It's the same as using a wheel with more offset. Will the outer bearings hold up?

lanciahf · Post by **lanciahf** » Mon Jan 01, 2007 8:55 am

Not to rain on your parade but

By moving the disk further out on the hub won't you lose the Hub centric mounting area for the wheels?

Also those parts look heavy, might increase steering effort or take the "spunky feel" out of the way the car feels.

fiatS2000 · Post by **fiatS2000** » Mon Jan 01, 2007 2:21 pm

I guess I should go back to the junk yard and get the power steering rack off the biturbo. It looks a lot like the manual rack I have off the 85.5.

I'm only doing this to see IF it can be done. I don't expect it to be perfect. If it doesn't work out, I can always use it on my dune buggy project. My friends and I already put a Fiat braking system on a Corvair dune buggy.

So Cal Mark · Post by **So Cal Mark** » Mon Jan 01, 2007 3:58 pm

by all means, don't let us stifle your creativity. I think we all want these endeavors to succeed, just consider the comments part of the brain-storming process

lanciahf · Post by **lanciahf** » Mon Jan 01, 2007 4:53 pm

By all means FiatS2000 please proceed I was just throwing things out there.

I forgot where I read it, maybe on mira? But someone else mentioned the 85.5 spiders used a biturbo rack. Can anyone confirm this?

Ralph

pastaroni · Post by **pastaroni** » Tue Jan 02, 2007 2:22 am

I guess I wasnt quite clear on my first post.. the inside of the rotor hat needs to fit on the outside of the wheel hub. this is what centers the rotors. I have seen brake designs that do not incorporate this feature, so I guess you can try it if you'd like. Personally though I wouldnt. Since the rotor hat is larger though it would be easy to make it fit with a centering ring. (especially since you need to space it out anyhow)

racydave · Post by **racydave** » Tue Jan 02, 2007 6:03 pm

I wouldnt think you could use spacers behind the rotor this is a critical attitude point and the lateral runout would be off, the rotor would wobble, the brakes would pulsate. If you had a special plate spacer made, You could check the runout and use shims behind the rotors, thats what GM is having their techs do nowadays.